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Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2016	Feb. 28, 2017	Jun. 30, 2016
Document Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	FY
Trading Symbol	GEVO
Entity Registrant Name	GEVO, INC.
Entity Central Index Key	0001392380
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		14,910,334
Entity Public Float			$ 52,648,520

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 27,888	$ 17,031
Accounts receivable	1,122	1,391
Inventories	3,458	3,487
Prepaid expenses and other current assets	850	731
Total current assets	33,318	22,640
Property, plant and equipment, net	75,592	76,777
Restricted deposits	2,611	2,611
Deposits and other assets	803	803
Total assets	112,324	102,831
Current liabilities:
Accounts payable and accrued liabilities	6,193	7,476
Current portion of secured debt, net		330
Current Portion of 2017 Notes recorded at fair value	25,769
Derivative warrant liability	2,698	10,493
Total current liabilities	34,660	18,299
Long-term portion of secured debt, net		153
Long Term portion of 2017 Notes recorded at fair value		21,565
2022 Notes, net	8,221	14,341
Other long-term liabilities	179	147
Total liabilities	43,060	54,505
Commitments and Contingencies (see Note 16)
Stockholders' Equity
Common stock, $0.01 par value per share; 250,000,000 authorized; 7,074,246 and 1,080,352 shares issued and outstanding at December 31, 2016 and 2015, respectively. (See Note 2)	71	10
Additional paid-in capital	445,913	387,808
Accumulated deficit	(376,720)	(339,492)
Total stockholders' equity	69,264	48,326
Total liabilities and stockholders' equity	$ 112,324	$ 102,831

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	250,000,000	250,000,000
Common stock shares issued	7,074,246	1,080,352
Common stock, shares outstanding	7,074,246	1,080,352

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenue and cost of goods sold
Hydrocarbon revenue	$ 1,929	$ 1,694	$ 3,949
Grant and other revenue	671	1,318	768
Total revenues	27,213	30,137	28,266
Cost of goods sold	37,017	38,762	35,582
Gross loss	(9,804)	(8,625)	(7,316)
Operating expenses
Research and development expense	5,216	6,610	14,120
Selling, general and administrative expense	8,965	16,692	18,341
Total operating expenses	14,181	23,302	32,461
Loss from operations	(23,985)	(31,927)	(39,777)
Other (expense) income
Interest expense	(7,837)	(8,243)	(8,255)
Interest expense - debt issue costs			(3,769)
Gain (Loss) on exchange or conversion of debt	(763)	232
Gain (Loss) on extinguishment of warrant liability	(918)	1,775
Gain from change in fair value of embedded derivative of the 2022 Notes			3,470
Gain from change in fair value of derivative warrant liability	1,783	577	6,530
Gain (Loss) from change in fair value of 2017 Notes	(4,204)	3,895	648
Loss on issuance of equity	(1,519)	(2,523)
Other income	215	20	8
Total other (expense) income	(13,243)	(4,267)	(1,368)
Net loss	$ (37,228)	$ (36,194)	$ (41,145)
Net loss per share - basic and diluted	$ (9.68)	$ (51.61)	$ (153.35)
Weighted-average number of common shares outstanding - basic and diluted	3,847,421	701,252	268,308
Ethanol
Revenue and cost of goods sold
Sales	$ 24,613	$ 27,125	$ 23,549

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid In Capital	Accumulated Deficit
Beginning Balance at Dec. 31, 2013	$ 70,975	$ 2	$ 333,126	$ (262,153)
Beginning Balance (in shares) at Dec. 31, 2013		228,310
Issuance of restricted stock (in shares)		3,794
Issuance of common stock, net of issue costs and warrants	14,223	$ 1	14,222
Issuance of common stock, net of issue costs and warrants (in shares)		100,000
Cancellation of restricted stock (in shares)		(220)
Issuance of common stock for services, upon exercise of stock options and pursuant to an employee stock purchase plan	51		51
Issuance of common stock for services, upon exercise of stock options and pursuant to an employee stock purchase plan (in shares)		210
Non-cash stock-based compensation	2,860		2,860
Net loss	(41,145)			(41,145)
Ending Balance at Dec. 31, 2014	46,964	$ 3	350,259	(303,298)
Ending Balance (in shares) at Dec. 31, 2014		332,094
Shares issued upon reverse stock split (in shares)		34
Issuance of restricted stock (in shares)		23,791
Issuance of common stock, net of issue costs and warrants	22,446	$ 4	22,442
Issuance of common stock, net of issue costs and warrants (in shares)		428,333
Cancellation of restricted stock (in shares)		(37)
Issuance of common stock for services, upon exercise of stock options and pursuant to an employee stock purchase plan	3		3
Issuance of common stock for services, upon exercise of stock options and pursuant to an employee stock purchase plan (in shares)		38
Non-cash stock-based compensation	2,647		2,647
Issuance of common stock upon exercise of warrants	10,166	$ 2	10,164
Issuance of common stock upon exercise of warrants (in shares)		232,205
Issuance of common stock upon conversion of debt	714		714
Issuance of common stock upon conversion of debt (in shares)		8,502
Issuance of common stock upon exchange of debt	1,580	$ 1	1,579
Issuance of common stock upon exchange of debt (in shares)		55,392
Net loss	(36,194)			(36,194)
Ending Balance at Dec. 31, 2015	48,326	$ 10	387,808	(339,492)
Ending Balance (in shares) at Dec. 31, 2015		1,080,352
Shares issued upon reverse stock split (in shares)		4
Issuance of common stock under stock plans, net (in shares)		2,782
Issuance of common stock, net of issue costs and warrants	34,224	$ 25	34,199
Issuance of common stock, net of issue costs and warrants (in shares)		2,480,094
Cancellation of restricted stock (in shares)		(4)
Non-cash stock-based compensation	886		886
Issuance of common stock upon exercise of warrants	12,298	$ 26	12,272
Issuance of common stock upon exercise of warrants (in shares)		2,559,218
Issuance of common stock upon exchange of debt	10,758	$ 10	10,748
Issuance of common stock upon exchange of debt (in shares)		951,800
Net loss	(37,228)			(37,228)
Ending Balance at Dec. 31, 2016	$ 69,264	$ 71	$ 445,913	$ (376,720)
Ending Balance (in shares) at Dec. 31, 2016		7,074,246

Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
Consolidated Statements of Cash Flows - USD ($)	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Activities
Net loss	$ (37,228,000)	$ (36,194,000)	$ (41,145,000)
Adjustments to reconcile net loss to net cash used in operating activities:
(Gain) from the change in fair value of derivative warrant liability	(1,783,000)	(577,000)	(6,530,000)
(Gain) from the change in fair value of the embedded derivative to the 2022 Notes			(3,470,000)
Loss/(Gain) from the change in fair value of 2017 Notes	4,204,000	(3,895,000)	(648,000)
Loss/(Gain) on exchange or conversion of debt	763,000	(232,000)
Loss/(Gain) on extinguishment of warrant liability	918,000	(1,775,000)
Loss on issuance of equity	1,519,000	2,523,000
Stock-based compensation	886,000	2,647,000	2,860,000
Depreciation and amortization	6,747,000	6,573,000	4,880,000
Non-cash interest expense	3,977,000	3,772,000	7,860,000
Other non-cash expenses	(1,000)	(7,000)	66,000
Changes in operating assets and liabilities:
Accounts receivable	269,000	970,000	(1,003,000)
Inventories	29,000	805,000	(711,000)
Prepaid expenses and other current assets	(119,000)	1,000	431,000
Accounts payable, accrued expenses, and long-term liabilities	(697,000)	(2,771,000)	(1,580,000)
Net cash used in operating activities	(20,516,000)	(28,160,000)	(38,990,000)
Investing Activities
Acquisitions of property, plant and equipment	(5,938,000)	(1,464,000)	(4,894,000)
Restricted certificate of deposit			(2,611,000)
Proceeds from sales tax refund for property, plant and equipment		144,000
Net cash used in investing activities	(5,938,000)	(1,320,000)	(7,505,000)
Financing Activities
Payments on secured debt	(504,000)	(318,000)	(9,824,000)
Debt and equity offering costs	(3,144,000)	(3,519,000)	(5,873,000)
Proceeds from issuance of common stock upon exercise of stock options and employee stock purchase plan		3,000	19,000
Proceeds from issuance of common stock and common stock warrants	28,661,000	33,820,000	18,000,000
Proceeds from issuance of convertible debt, net			25,907,000
Proceeds from the exercise of warrants	12,298,378	10,166,000
Net cash provided by financing activities	37,311,000	40,152,000	28,229,000
Net increase (decrease) in cash and cash equivalents	10,857,000	10,672,000	(18,266,000)
Cash and cash equivalents
Beginning of year	17,031,000	6,359,000	24,625,000
Ending of year	27,888,000	17,031,000	6,359,000
Supplemental disclosures of cash and non-cash investing and financing transactions
Conversion and exchanges of convertible debt for common stock	10,758,000	2,294,000
Cash paid for interest, net of interest capitalized		4,589,000	4,213,000
Capitalization of interest, from term to 2017 convertible notes			201,000
Non-cash purchase of property, plant and equipment	513,000	890,000	108,000
Accrued offering costs		648,000
Issuance of common stock for services			31,000
Fair value of warrants at issuance and upon exercise, net	$ 6,668,000	$ (7,951,000)	$ 2,400,000

Nature of Business and Financial Condition	12 Months Ended
Nature of Business and Financial Condition	Dec. 31, 2016
Accounting Policies [Abstract]
Nature of Business and Financial Condition	1. Nature of Business and Financial Condition Nature of Business. Gevo, Inc. (“Gevo” or the “Company,” which, unless otherwise indicated, refers to Gevo, Inc. and its subsidiaries) is a renewable chemicals and next generation biofuels company focused on the development and commercialization of alternatives to petroleum-based products based on isobutanol produced from renewable feedstocks. Gevo, Inc. was incorporated in Delaware on June 9, 2005. Gevo, Inc. formed Gevo Development, LLC (“Gevo Development”) in September 2009 to finance and develop biorefineries through joint venture, licensing arrangements, tolling arrangements or direct acquisition (see Note 12 Gevo Development for more information on Gevo Development). Gevo Development became a wholly-owned subsidiary of the Company in September 2010. Gevo Development purchased Agri-Energy, LLC (“Agri-Energy”) in September 2010. Through May 2012, Agri-Energy, a wholly-owned subsidiary of Gevo Development, was engaged in the business of producing and selling ethanol and related products produced at its plant located in Luverne, Minnesota (the “Agri-Energy Facility”). The Company commenced the retrofit of the Agri-Energy Facility in 2011 and commenced initial startup operations for the production of isobutanol at this facility in May 2012. In September 2012, the Company made the strategic decision to pause isobutanol production at the Agri-Energy Facility to focus on optimizing specific parts of the process to further enhance isobutanol production rates. In 2013, the Company modified the Agri-Energy Facility in order to increase the isobutanol production rate. In June 2013, the Company resumed the limited production of isobutanol, operating one fermenter and one Gevo Integrated Fermentation Technology^® (“GIFT^®”) separation system in order to (i) verify that the modifications had significantly reduced the previously identified infections, (ii) demonstrate that its biocatalyst performs in the one million liter fermenters at the Agri-Energy Facility, and (iii) confirm GIFT^® efficacy at commercial scale at the Agri-Energy Facility. In August 2013, the Company expanded production capacity at the Agri-Energy Facility by adding a second fermenter and second GIFT^® system to further verify its results with a second configuration of equipment. In October 2013, the Company began commissioning the Agri-Energy Facility on corn mash to test isobutanol production run rates and to optimize biocatalyst production, fermentation separation and water management systems. In March 2014, the Company decided to leverage the flexibility of its GIFT^® technology and make further modifications to the Agri-Energy Facility which it believed would enable the simultaneous production of isobutanol and ethanol. In July 2014, the Company began more consistent co-production of isobutanol and ethanol at the Agri-Energy Facility, with one fermenter utilized for isobutanol production and three fermenters utilized for ethanol production. In line with the Company’s strategy to maximize asset utilization and site cash flows, the Company believes that this configuration of the plant should allow it to continue to optimize its isobutanol technology at a commercial scale, while taking advantage of potentially superior ethanol contribution margins. As of December 31, 2016, the Company continues to engage in research and development, business development, business and financial planning, optimize operations for isobutanol, hydrocarbon and ethanol production and raise capital to fund future expansion of our Agri-Energy Facility for increased isobutanol and hydrocarbon production. Ultimately, the Company believes that the attainment of profitable operations is dependent upon future events, including (i) completing its development activities resulting in commercial production and sales of isobutanol or isobutanol-derived products and/or technology, (ii) obtaining adequate financing to complete its development activities, (iii) obtaining adequate financing to build out further isobutanol production capacity, (iv) gaining market acceptance and demand for its products and services, and (v) attracting and retaining qualified personnel. The Company has primarily derived revenue from the sale of ethanol, distiller’s grains and other related products produced as part of the ethanol production process at the Agri-Energy Facility. The production of ethanol alone is not the Company’s intended business and its future strategy is expected to depend on its ability to produce and market isobutanol and products derived from isobutanol. Given that the production of ethanol alone is not the Company’s intended business, and the Company is only beginning to achieve more consistent production and revenue from the sale of isobutanol, the historical operating results of Agri-Energy may not be indicative of future operating results for Agri-Energy or Gevo. Financial Condition. For the year ended December 31, 2016, the Company incurred a consolidated net loss of $37.2 million and had an accumulated deficit of $376.7 million. The Company’s cash and cash equivalents at December 31, 2016 totaled $27.9 million which is primarily being used for the following: (i) operating activities and completion of the side-by-side configuration of the Agri-Energy Facility; (ii) operating activities at its corporate headquarters in Colorado, including research and development work; (iii) capital improvements primarily associated with its Agri-Energy Facility; (iv) costs associated with optimizing isobutanol production technology; and (v) debt service obligations. The Company expects to incur future net losses as it continues to fund the development and commercialization of its product candidates. The Company’s transition to profitability is dependent upon, among other things, the successful development and commercialization of its product candidates and the achievement of a level of revenues adequate to support the Company’s cost structure. The Company may never achieve profitability or positive cash flows, and unless and until it does, the Company will continue to need to raise additional cash. Management intends to fund future operations through additional private and/or public offerings of debt or equity securities. In addition, the Company may seek additional capital through arrangements with strategic partners or from other sources, it may seek to restructure its secured debt and it will continue to address its cost structure. Notwithstanding, there can be no assurance that the Company will be able to raise additional funds, or achieve or sustain profitability or positive cash flows from operations. Based on the Company’s current operating plan, existing working capital at December 31, 2016 was not sufficient to meet the cash requirements to fund planned operations through the period that is one year after the date the Company’s 2016 financial statements are issued unless the Company is able to restructure and extend its debt obligations and/or raise additional capital to fund operations. These conditions raise substantial doubt about the Company’s ability to continue as a going concern at December 31, 2016. The Company’s inability to continue as a going concern may potentially affect the Company’s rights and obligations under its Senior Secured Debt and Convertible Notes. The accompanying financial statements have been prepared assuming that the Company will continue as a going concern and do not include adjustments that might result from the outcome of this uncertainty. This basis of accounting contemplates the recovery of the Company’s assets and the satisfaction of liabilities in the normal course of business. See Note 8 Senior Secured Debt, Secured Debt and Convertible Debt for information on the Company’s debt obligations.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2016

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Principles of Consolidation. The consolidated financial statements of Gevo include the accounts of its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.

Basis of Presentation. The consolidated financial statements of the Company (which include the accounts of its wholly-owned subsidiaries Gevo Development and Agri-Energy) have been prepared pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (the “SEC”) and accounting principles generally accepted in the U.S. for complete financial statements. These statements reflect all normal and recurring adjustments which, in the opinion of management, are necessary to present fairly the financial position, results of operations and cash flows of the Company at December 31, 2016.

Reverse Stock Splits. On December 14, 2016, the Board of Directors approved an amendment to its Amended and Restated Certificate of Incorporation to effect a reverse stock split of the Company’s common stock, par value $0.01 at a ratio of one-for-twenty. The reverse stock split became effective January 5, 2017. On April 15, 2015, the Board of Directors of the Company approved a reverse split of the Company’s common stock, at a ratio of one-for-fifteen. This reverse stock split became effective on April 20, 2015. Unless otherwise indicated, all share amounts, per share data, share prices, exercise prices and conversion rates set forth in these notes and the accompanying consolidated financial statements have, where applicable, been adjusted retroactively to reflect both of these reverse stock splits.

Use of Estimates. The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ materially from those estimates.

Concentrations of Credit Risk. The Company’s financial instruments that are exposed to concentrations of credit risk consist of cash and cash equivalents in excess of the federally insured limits. The Company’s cash and cash equivalents are deposited with high credit-quality financial institutions and are primarily in demand deposit accounts.

Cash and Cash Equivalents. The Company maintains its cash and cash equivalents in highly liquid interest bearing money market accounts or non-interest bearing demand accounts. The Company considers all highly liquid investments purchased with a maturity of three months or less at the date of acquisition to be cash equivalents.

Accounts Receivable. The Company records receivables for products shipped and services provided but for which payment has not yet been received. As of December 31, 2016 and 2015, no allowance for doubtful accounts has been recorded, based upon the expected full collection of the accounts receivable. As of December 31, 2016 and 2015, one customer, C&N Ethanol Marketing, LLC comprised 53% and 56%, respectively, of our outstanding trade accounts receivable.

Inventories. Inventory is recorded at the lower of cost or market value and cost of goods sold is determined by average cost method. Ethanol and isobutanol inventory cost consists of the applicable share of raw material, direct labor and manufacturing overhead costs. Spare Parts inventory consists of the parts required to maintain and operate the Company’s Luverne, Minnesota facility and is recorded at cost.

Restricted Deposits. The Company maintains a restricted deposit related to the 2017 Notes (defined below) that is equivalent to ten percent of the principal balance. The balance at December 31, 2016 and 2015 was $2.6 million.

Derivative Instruments. The Company evaluates its contracts for potential derivatives which Gevo, Inc. uses to raise capital. See Note 6 for a description of the Company’s accounting for embedded derivatives and Note 7 for a description of the Company’s derivative warrant liability. At issuance date, derivative warrant liabilities are initially recognized as a liability with a corresponding reduction in stockholders’ equity. Changes in the estimated fair value of the derivative warrant liability between issuance date and exercise/expiration date represents an unrealized (gain)/loss and is recognized and recorded in the Consolidated Statement of Operations. The fair value of the derivative warrant liability is ultimately either reclassed into equity upon either exercise or, if expired, a realized (gain)/loss is recognized and recorded in the Consolidted Statement of Operation.

As of December 31, 2016 and 2015, the Company did not have any forward purchase contracts or exchange-traded futures contracts.

Property, Plant and Equipment. Property, plant and equipment are recorded at cost less accumulated depreciation and amortization. Depreciation and amortization are computed using the straight-line method over the assets’ estimated useful lives. Leasehold improvements are amortized over the term of the lease agreement or the service lives of the improvements, whichever is shorter. Assets under construction are depreciated when they are placed into service. Maintenance and repairs are charged to expense as incurred and expenditures for major improvements are capitalized.

Impairment of Property, Plant and Equipment. The Company’s property, plant and equipment consist primarily of assets associated with the acquisition and retrofit of the Agri-Energy Facility. The Company assesses impairment of property, plant and equipment for recoverability when events or changes in circumstances indicate that their carrying amount may not be recoverable. Circumstances which could trigger a review include, but are not limited to: significant decreases in the market price of the asset; significant adverse changes in the business climate, or legal or regulatory factors; accumulation of costs significantly in excess of the amount originally expected for the acquisition or construction of the asset; or expectations that the asset will more likely than not be sold or disposed of significantly before the end of its estimated useful life. The carrying amount of a long-lived asset is considered to be impaired if it exceeds the sum of the undiscounted cash flows expected to result from the use and eventual disposition of the assets.

The Company evaluated its Agri-Energy Facility for impairment as of December 31, 2016 and 2015. These evaluations included comparing the carrying amount of the acquisition and retrofit of the Agri-Energy Facility to the estimated undiscounted future cash flows at the Agri-Energy Facility as this represents the lowest level of identifiable cash flows. Significant assumptions included in the estimated undiscounted future cash flows include, among others, estimates of the:

•

sales price of isobutanol, hydrocarbons, ethanol and by-products such as dried distiller’s grains;

•

purchase price of corn;

•

production levels of isobutanol;

•

capital and operating costs to produce isobutanol; and

•

estimated useful life of the primary asset.

Factors which can impact these assumptions include, but are not limited to;

•

effectiveness of the Company’s technology to produce isobutanol at targeted margins;

•

demand for isobutanol and oil prices; and

•

harvest levels of corn.

Based upon the Company’s evaluation at December 31, 2016 and 2015, the Company concluded that the estimated undiscounted future cash flows from the Agri-Energy Facility exceeded the carrying value and, as such, these assets were not impaired. Although the Company’s cash flow forecasts are based on assumptions that are consistent with its planned use of the assets, these estimates required significant exercise of judgment and are subject to change in future reporting periods as facts and circumstances change. Additionally, the Company may make changes to its business plan that could result in changes to the expected cash flows. As a result, it is possible that a long-lived asset may be impaired in future reporting periods.

Debt at Fair Value Option. The Company has elected the fair value option for certain long-term debt instruments that qualify for such treatment. See Note 8 for a detailed description of the accounting for the 2017 convertible notes that are accounted for in such manner.

Debt Issue Costs. Debt issue costs are costs incurred in connection with the Company’s debt financings that primarily have been capitalized and are being amortized over the stated maturity period or estimated life of the related debt, using the effective interest method.

Revenue Recognition. The Company records revenue from the sale of hydrocarbon products, ethanol and related products, including the sale of corn inventory. The Company recognizes revenue when all of the following criteria are satisfied: persuasive evidence of an arrangement exists; risk of loss and title transfer to the customer; the price is fixed or determinable; and collectability is reasonably assured. Ethanol and related products are generally shipped free on board shipping point. Collectability of revenue is reasonably assured based on historical evidence of collectability between the Company and its customers. In accordance with the Company’s agreements for the marketing and sale of ethanol and related products, commissions due to marketers were deducted from the gross sales price at the time payment was remitted. Ethanol and related products sales were recorded net of commissions.

Revenue related to government research grants and cooperative agreements is recognized in the period during which the related costs are incurred, provided that the conditions under the awards have been met and only perfunctory obligations are outstanding. Revenues related to the lease agreements are recognized on a straight-line basis over the term of the contract.

In 2016, 2015 and 2014, C&N Ethanol Marketing, LLC accounted for approximately 75%, 73% and 71% of our consolidated revenue, respectively. In the same years, Land O’Lakes Purina Feed LLC accounted for approximately 18%, 19% and 13% of our consolidated revenue, respectively. Given our production capacity compared to the overall size of the North American market and the demand for our products, we do not believe that a decline in a specific customer's purchases would have a material adverse long-term effect upon our financial results.

Cost of Goods Sold. Cost of goods sold includes costs incurred in conjunction with the operations for the production of isobutanol at the Agri-Energy Facility and costs directly associated with the ethanol and related products production process such as costs for direct materials, direct labor and certain plant overhead costs. Costs associated with the operations for the production of isobutanol includes costs for direct materials, direct labor, plant utilities, including natural gas, and plant depreciation. Direct materials consist of dextrose for initial production of isobutanol, corn feedstock, denaturant and process chemicals. Direct labor includes compensation of personnel directly involved in production operations at the Agri-Energy Facility. Costs of direct materials for the production of ethanol and related products consist of corn feedstock, denaturant and process chemicals. Direct labor includes compensation of personnel directly involved in the operation of the Agri-Energy Facility. Plant overhead costs primarily consist of plant utilities and plant depreciation. Cost of goods sold is mainly affected by the cost of corn and natural gas. Corn is the most significant raw material cost. The Company purchases natural gas to power steam generation in the production process and to dry the distiller’s grains, a by-product of ethanol and related products production.

Patents. All costs related to filing and pursuing patent applications are expensed as incurred as recoverability of such expenditures is uncertain. Patent-related legal expenses incurred are recorded as selling, general and administrative expense, and during the years ended December 31, 2016, 2015 and 2014 were $0.2 million, $0.9 million, and $0.9 million, respectively.

Research and Development. Research and development costs are expensed as incurred and are recorded as research and development expense in the Consolidated Statement of Operations. The Company’s research and development costs consist of expenses incurred to identify, develop, and test its technologies for the production of isobutanol and the development of downstream applications thereof. Research and development expense includes personnel costs, consultants and related contract research, facility costs, supplies, depreciation on property, plant and equipment used in development, license fees and milestone payments paid to third parties for use of their intellectual property and patent rights, and other direct and allocated expenses incurred to support the Company’s overall research and development programs.

Income Taxes. Deferred tax assets and liabilities are recognized based on the difference between the carrying amounts of assets and liabilities in the financial statements and their respective tax bases. Deferred tax assets and liabilities are measured using currently enacted tax rates in effect in the years in which those temporary differences are expected to reverse. Deferred tax assets should be reduced by a valuation allowance if, based on the weight of available evidence, it is more likely than not that some portion or all of the deferred tax assets will not be realized. At December 31, 2016 and 2015, based upon current facts and circumstances, the Company had recorded a valuation allowance against its deferred tax assets of $139.3 million and $134.1 million, respectively.

Stock-Based Compensation. The Company’s stock-based compensation expense includes expenses associated with share-based awards granted to employees and board members, and expenses associated with awards under its employee stock purchase plan (“ESPP”). Stock-based compensation expense for all share-based payment awards granted is based on the grant date fair value. The grant date fair value for stock option awards is estimated using the Black-Scholes option pricing model and the grant date fair value for restricted stock awards is based upon the closing price of the Company’s common stock on the date of grant. The Company recognizes compensation costs for share-based payment awards granted to employees net of estimated forfeitures and recognizes stock-based compensation expense for only those awards expected to vest on a straight-line basis over the requisite service period of the award, which is currently the vesting term of up to four years. For performance based restricted stock awards, the Company recognizes expense over the requisite service period.

Net Loss Per Share. Basic net loss per share is computed by dividing the net loss attributable to Gevo, Inc. common stockholders for the period by the weighted-average number of common shares outstanding during the period. Diluted earnings per share (“EPS”) includes the dilutive effect of common stock equivalents and is computed using the weighted-average number of common stock and common stock equivalents outstanding during the reporting period. Diluted EPS for the years ending December 31, 2016, 2015, and 2014 excluded common stock equivalents because the effect of their inclusion would be anti-dilutive, or would decrease the reported loss per share.

The following table sets forth securities that could potentially dilute the calculation of diluted earnings per share. This table excludes any shares that could potentially be issued in settlement of make-whole payments associated with the 2017 Notes and the 2022 Notes.

	Year Ended December 31,
	2016		2015		2014
Warrants to purchase common stock		1,103,766		1,024,635		125,212
Convertible 2017 notes		75,119		75,191		75,127
Convertible 2022 notes		5,608		13,117		15,752
Outstanding options to purchase common stock		16,915		24,089		12,245
Unvested restricted common stock		8,823		16,413		2,918
Total		1,210,231		1,153,445		231,254

The following table sets forth additional securities transactions that had they occurred in 2016 would have further diluted the calculation for earnings/ (loss) per share:


	Date	Shares
2022 Note exchanges	January 2017		2,155,382
Issuance of common stock	February 2017		5,680,000
Exercise of Series L Warrants	March 2017		155,000
Total			7,990,382

Recent Accounting Pronouncements

Revenue from Contracts with Customers (“ASU 2014-09”). In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers. The objective of ASU 2014-09 is to outline a new, single comprehensive model to use in accounting for revenue arising from contracts with customers. The new revenue recognition model provides a five-step analysis for determining when and how revenue is recognized, depicting the transfer of promised goods or services to customers in an amount that reflects the consideration that is expected to be received in exchange for those goods or services. ASU 2014‑09 is effective for fiscal years and interim periods within those years beginning after December 15, 2016. Early adoption is permitted. On July 9, 2015, the FASB Board voted to delay the implementation of ASU 2014-09 by one year to December 15, 2017. In April 2016, the FASB issued Accounting Standards Update No. 2016-10 Revenue from Contracts with Customers, Identifying Performance Obligations and Licensing (“ASU 2016-10”) which provides additional clarification regarding Identifying Performance Obligations and Licensing. The new standard is required to be applied retrospectively to each prior reporting period presented or retrospectively with the cumulative effect of initially applying it recognized at the date of initial application. The Company has not yet selected a transition method. The Company does not anticipate the new standard to materially impact how it accounts for its (a) ethanol and related products revenue and (b) hydrocarbon revenue. However, we are currently evaluating the impact to our grant revenue as there could be a potential for changes to the nature and timing of revenue recognized under our various grant agreements.

Simplifying the Measurement of Inventory (“ASU 2015-11”). In July 2015, the FASB issued ASU 2015-11, Simplifying the Measurement of Inventory which requires an entity to measure in scope inventory at the lower of cost and net realizable value. Subsequent measurement is unchanged for inventory measured using LIFO or the retail inventory method. The amendments do not apply to inventory that is measured using last-in, first-out (LIFO) or the retail inventory method. The amendments apply to all other inventory, which includes inventory that is measured using first-in, first-out (FIFO) or average cost. The amendments are effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. The amendments should be applied prospectively with earlier application permitted as of the beginning of an interim or annual reporting period. The Company is currently in the process of evaluating the impact of adoption of ASU 2015-11 on its consolidated balance sheets.

Leases (“ASU 2016-02”). In February 2016, the FASB issued Accounting Standards Update No. 2016-02, Topic 842 Leases. ASU-2016-02 requires leases to be reported on the financial statements. The objective is to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. This Update are effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Future minimum lease obligations for leases accounted for as operating leases at December 31, 2016 totaled $4.5 million. The Company is currently in the process of evaluating the impact of adoption of ASU 2016-02 on our consolidated financial statements.

Derivatives and Hedging (Topic 815) Contingent Put and Call Options in Debt Instruments (“ASU 2016-06”). In March 2016, the FASB issued Accounting Standards Update No. 2016-06, Derivatives and Hedging (Topic 815) Contingent Put and Call Options in Debt Instruments. Topic 815 requires that embedded derivatives be separated from the host contract and accounted for separately as derivatives if certain criteria are met. There are two approaches for determining if the criteria are met. The objective of ASU 2016-06 is intended to resolve the diversity in practice resulting from those two approaches. This Update are effective for financial statements issued for fiscal years beginning after December 15, 2016, and interim periods within those fiscal years. The Company has reviewed the new standard and determined that it will not change the Company’s accounting.

Compensation—Stock Compensation (‘ASU 2016-09”). In March 2016, the FASB issued Accounting Standards Update No. 2016-09, Compensation—Stock Compensation. This standard was issued as part of its Simplification Initiative. The objective of the Simplification Initiative is to identify, evaluate, and improve areas of generally accepted accounting principles (GAAP) for which cost and complexity can be reduced while maintaining or improving the usefulness of the information provided to users of financial statements. The areas for simplification in this Update involve several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. The amendments in this Update are effective for annual periods beginning after December 15, 2016, and interim periods within those annual periods. Early adoption is permitted. The Company is currently in the process of evaluating the impact of adoption of ASU 2016-09 on its consolidated financial statements.

Statement of Cash Flows, Classification of Certain Cash Receivable and Cash Payments (“ASU 2016-15). In August 2016, the FASB issued Accounting Standards Update No. 2016-15, Statement of Cash Flows Classification of Certain Cash Receipts and Cash Payments which clarifies cash flow statement classification of eight specific cash flow issues. The purpose of ASU 2016-15 is to provide clarification and consistency for classifying the eight specific cash flow issues because current GAAP either is unclear or does not include specific guidance. The amendments in the update are effective for public business entities for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. The Company is currently in the process of evaluating the impact of adoption of ASU 2016-15 on its consolidated statements of cash flows.

Adoption of New Accounting Pronouncements.

Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (“ASU 2014-15”. ) In August 2014, the FASB issued Accounting Standards Update No. 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern. The objective of ASU 2014-15 is to provide guidance in GAAP about management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to provide related footnote disclosures. ASU 2015-15 requires a management evaluation about whether there are conditions or events, considered in the aggregate, that raise substantial doubt about an entity’s ability to continue as a going concern within one year after the date the financial statements are issued or available to be issued. In doing so, ASU 2014-15 should reduce diversity in the timing and content of footnote disclosures. The Company adopted this standard for the year-ended December 31, 2016 through the disclosure regarding its financial condition in Note 1 – Nature of Business and Financial Condition.

Balance Sheet Classification of Deferred Income Taxes (“ASU 2015-17”). In November 2015, the FASB issued Accounting Standards Update No. 2015-17, Balance Sheet Classification of Deferred Income Taxes. This standard is issued as part of its Simplification Initiative. The objective of the Simplification Initiative is to identify, evaluate, and improve areas of generally accepted accounting principles (GAAP) for which cost and complexity can be reduced while maintaining or improving the usefulness of the information provided to users of financial statements. The amendments in this Update require that deferred tax liabilities and assets be classified as noncurrent in a classified statement of financial position. The amendments in this update are effective for financial statements issued for annual periods beginning after December 15, 2016, and interim periods within those annual periods. The Company has elected to early adopt this standard for the year-ended December 31, 2016. Adoption of this standard does not materially impact the presentation of the Company’s consolidated balance sheets as it continues to estimate a one-hundred percent valuation allowance reducing net deferred income taxes to $0.

Simplifying the Presentation of Debt Issuance Costs (“ASU 2015-03”) . In April 2015, the FASB issued Accounting Standards Update No. 2015-03 Simplifying the Presentation of Debt Issuance Costs intended to simplify the presentation of debt issuance costs. These amendments require that debt issuance costs be presented as a direct deduction from the carrying amount of the related debt liabilities, consistent with the presentation of debt discounts. This will result in the elimination of debt issuance costs as an asset and will reduce the carrying value of the Company’s debt liabilities. This guidance is effective for annual reporting periods, and interim periods within those annual periods, beginning after December 15, 2015. The Company has adopted the guidance as of January 1, 2016. The adoption of this guidance had an immaterial impact on our financial position and has resulted in the following retrospective adjustments to our consolidated balance sheet at December 31, 2015 (in thousands):

	December 31, 2015
	As reported		As adjusted
Total Assets	$	103,128	$	102,831
Current portion of secured debt, net	$	332	$	330
2022 Notes, net	$	14,636	$	14,341

Inventories

12 Months Ended

Dec. 31, 2016

Inventory Disclosure [Abstract]

Inventories

3. Inventories

The following table sets forth the components of the Company’s inventory balances (in thousands).

	December 31,
	2016		2015
Raw materials
Corn	$	108	$	517
Enzymes and other inputs		309		283
Nutrients		10		4
Finished goods
Ethanol		72		172
Isobutanol		755		-
Jet Fuels, Isooctane and Isooctene		519		514
Distiller's grains		-		13
Work in process - Agri Energy		274		460
Work in process - Gevo		62		109
Spare parts		1,349		1,415
Total inventories	$	3,458	$	3,487

Work in process inventory includes unfinished jet fuel, isooctane, isooctene and isobutanol inventory. Prior to 2016, finished isobutanol located at our Agri-Energy Facility was classified within Work in process – Agri-Energy given the majority of our isobutanol production was being used as feedstock to produce hydrocarbons such as jet fuel, isooctane and isooctene. During 2016, the Company chose to classify isobutanol as a component of finished goods due to the increased production of isbutanol at our Agri-Energy Facility and the positive market development and customer demand for isobutanol being sold directly into the market as a gasoline blendstock.

Property, Plant and Equipment

12 Months Ended

Dec. 31, 2016

Property Plant And Equipment [Abstract]

Property, Plant and Equipment

4. Property, Plant and Equipment

The following table sets forth the Company’s property, plant and equipment by classification (in thousands).

		December 31,
		2016			2015
Construction in progress	-	$	293		$	1,801
Plant machinery and equipment (1)	10 years		15,397			14,113
Site improvements	10 years		7,050			7,039
Agri-Energy Retrofit asset (1)	20 years		70,791			65,457
Lab equipment, furniture and fixtures and vehicles	5 years		6,431			6,389
Demonstration plant	2 years		3,597			3,597
Buildings	10 years		2,543			2,543
Computer, office equipment and software	3 years		1,594			1,566
Leasehold improvements, pilot plant, land and support equipment	2 - 5 years		2,526			2,175
Total property, plant and equipment			110,222			104,680
Less accumulated depreciation and amortization			(34,630	)		(27,903	)
Property, plant and equipment, net		$	75,592		$	76,777

(1)

In May 2016, certain assets of the Agri-Energy retrofit asset were reclassified from plant, machinery and equipment to the Agri-Energy retrofit asset.

As of December 31, 2016 and 2015, the Company has $0.7 million and $0.7 million , respectively, of capital lease assets included in computer, office equipment and software. The Company recorded amortization of capital lease assets of $0.1 million during each of the years ended December 31, 2016, 2015 and 2014, as a component of depreciation and amortization in the consolidated statements of cash flows.

The Company recorded $6.7 million, $6.6 million, and $4.9 million of depreciation expense for the years ended December 31, 2016, 2015, and 2014, respectively, including $6.0 million, $5.7 million, and $4.0 million of depreciation expense in cost of goods sold for the years ended December 31, 2016, 2015 and 2014 respectively.

Accounts Payable and Accrued Liabilities

12 Months Ended

Dec. 31, 2016

Payables And Accruals [Abstract]

Accounts Payable and Accrued Liabilities

5. Accounts Payable and Accrued Liabilities

The following table sets forth the components of the Company’s accounts payable and accrued liabilities in the consolidated balance sheets (in thousands).

	December 31,
	2016		2015
Accounts payable - trade	$	2,611	$	2,691
Accrued legal-related fees		626		854
Accrued employee compensation		1,385		2,082
Accrued interest		359		840
Accrued taxes payable		136		138
Short-term capital lease		147		144
Other accrued liabilities *		929		727
Total accounts payable and accrued liabilities	$	6,193	$	7,476

*	Other accrued liabilities consist of franchise taxes, property taxes, audit fees, and a variety of other expenses, none of which individually represent greater than five percent of total current liabilities.

Embedded Derivatives	12 Months Ended
Embedded Derivatives	Dec. 31, 2016
Derivative Instruments And Hedging Activities Disclosure [Abstract]
Embedded Derivatives	6. Embedded Derivatives In July 2012, the Company issued 7.5% convertible senior notes due 2022 (the “2022 Notes”) which contain the following embedded derivatives: (i) rights to convert into shares of the Company’s common stock, including upon a Fundamental Change (as defined in the indenture governing the 2022 Notes (the “Indenture”)); and (ii) a Coupon Make-Whole Payment (as defined in the Indenture) in the event of a conversion by the holders of the 2022 Notes prior to July 1, 2017. Embedded derivatives are separated from the host contract, the 2022 Notes, and carried at fair value when: (a) the embedded derivative possesses economic characteristics that are not clearly and closely related to the economic characteristics of the host contract; and (b) a separate, stand-alone instrument with the same terms would qualify as a derivative instrument. The Company has concluded that the embedded derivatives within the 2022 Notes meet these criteria and, as such, must be valued separate and apart from the 2022 Notes and recorded at fair value each reporting period. The Company used a binomial lattice model in order to estimate the fair value of the embedded derivative in the 2022 Notes. A binomial lattice model generates two probable outcomes, whether up or down, arising at each point in time, starting from the date of valuation until the maturity date. A lattice model was initially used to determine if the 2022 Notes would be converted, called or held at each decision point. Within the lattice model, the following assumptions are made: (i) the 2022 Notes will be converted early if the conversion value is greater than the holding value; and (ii) the 2022 Notes will be called if the holding value is greater than both (a) the Redemption Price (as defined in the Indenture) and (b) the conversion value plus the Coupon Make-Whole Payment at the time. If the 2022 Notes are called, then the holders will maximize their value by finding the optimal decision between (1) redeeming at the Redemption Price and (2) converting the 2022 Notes. Using this lattice model, the Company valued these embedded derivatives using a “with-and-without method,” where the value of the 2022 Notes including the embedded derivative, is defined as the “with”, and the value of the 2022 Notes excluding the embedded derivative, is defined as the “without”. This method estimates the value of the embedded derivative by looking at the difference in the values between the 2022 Notes with the embedded derivative and the value of the 2022 Notes without the embedded derivative. The lattice model requires the following inputs: (i) price of Gevo common stock; (ii) Conversion Rate (as defined in the Indenture); (iii) Conversion Price (as defined in the Indenture); (iv) maturity date; (v) risk-free interest rate; (vi) estimated stock volatility; and (vii) estimated credit spread for the Company. Inputs used to estimate the value of the embedded derivative as of December 31, 2016 were substantially similar to those used as of the period ended December 31, 2015. Changes in certain inputs into the lattice model can have a significant impact on changes in the estimated fair value of the embedded derivatives. For example, the estimated fair value of the embedded derivatives will generally decrease with; (i) a decline in the stock price; (ii) a decrease in the estimated stock volatility; and (iii) a decrease in the estimated credit spread. As of December 31, 2016 and 2015, the estimated fair value of the embedded derivatives was zero. Any decline in the estimated fair value of the embedded derivatives represents an unrealized gain which has been recorded as gain from change in fair value of embedded derivatives in the consolidated statements of operations. The Company recorded the estimated fair value of the embedded derivative with the 2022 notes, net in the consolidated balance sheets.

- Definition

The entire disclosure for hybrid instruments and embedded derivatives, including discussion of the process used in evaluating whether a hybrid instrument in the form of a share constitutes a debt or equity security, and on what basis an embedded derivative was deemed to be separable or inseparable from the host instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 15
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=35708913&loc=d3e50883-113970

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 15
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=35708913&loc=d3e50896-113970

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 15
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35708913&loc=d3e50876-113970

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 15
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6437212&loc=d3e50806-113969

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 15
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=64798853&loc=d3e48542-113965

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624163-113959

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13495-108611

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Hybrid Instrument
-URI http://asc.fasb.org/extlink&oid=6514950

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Embedded Derivative
-URI http://asc.fasb.org/extlink&oid=6511375

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(n)(1),(7))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Derivative Warrant Liability

12 Months Ended

Dec. 31, 2016

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Derivative Warrant Liability

7. Derivative Warrant Liability

The following warrants were sold by the Company:

•

December 2013, the Company sold warrants to purchase 71,013 shares of the Company’s common stock (the “2013 Warrants”).

•

August 2014, the Company sold warrants to purchase 50,000 shares of the Company’s common stock (the “2014 Warrants”).

•

February 2015, the Company sold Series A warrants to purchase 110,833 shares of the Company’s common stock (the “Series A Warrants”) and Series B warrants to purchase 110,833 shares of the Company’s common stock (the “Series B Warrants”).

•

May 2015, the Company sold Series C warrants to purchase 21,500 shares of the Company’s common stock (the “Series C Warrants”).

•

December 2015, the Company sold Series D warrants to purchase 502,500 shares of the Company’s common stock (the “Series D Warrants”) and Series E warrants to purchase 400,000 shares of the Company’s common stock (the “Series E Warrants”).

•

April 2016, the Company sold 514,644 Series F warrants to purchase one share of common stock (the “Series F Warrant”) and 1,029,286 Series H warrants, each to purchase one share of common stock (the “Series H Warrant”), and 328,571 pre-funded Series G warrants (“Series G Warrants”) to purchase one share of common stock, pursuant to an underwritten public offering.

•

September 2016, the Company sold 712,503 Series I warrants to purchase one share of common stock (the “Series I Warrant”) and 185,000 pre-funded Series J warrants (“Series J Warrants”) to purchase one share of common stock, pursuant to an underwritten public offering.

The following sets forth information pertaining to shares issued upon the exercise of such warrants for the year ended December 31, 2016:

	Issuance Date	Expiration Date	Exercise Price as of December 31, 2016		Shares Underlying Warrants on Issuance Date		Shares Issued upon Warrant Exercises as of December 31, 2016			Shares Underlying Warrants Outstanding as of December 31, 2016
2013 Warrants	12/16/2013	12/16/2018	$	49.80		71,013		(15,239	)		55,774
2014 Warrants	8/5/2014	8/5/2019	$	36.20		50,000		(30,538	)		19,462
Series A Warrants	2/3/2015	2/3/2020	$	5.80		110,833		(99,416	)		11,417
Series B Warrants	2/3/2015	8/3/2015		-		110,833		(96,795	)		-
Series C Warrants	5/19/2015	5/19/2020	$	27.80		21,500		-			21,500
Series D Warrants	12/11/2015	12/11/2020	$	2.00		502,500		(501,570	)		930
Series E Warrants	12/11/2015	12/11/2020		-		400,000		(400,000	)		-
Series F Warrants	4/1/2016	4/1/2021	$	5.80		514,644		(233,857	)		280,787
Series G Warrants	4/1/2016	4/1/2017		-		328,571		(328,571	)		-
Series H Warrants	4/1/2016	10/1/2016		-		1,029,286		(900,436	)		-
Series I Warrants	9/13/2016	9/13/2021	$	11.00		712,503		-			712,503
Series J Warrants	9/13/2016	9/13/2017		-		185,000		(185,000	)		-
						4,036,683		(2,791,422	)		1,102,373

The agreements governing the above warrants include the following terms:

•

certain warrants have exercise prices which are subject to adjustment for certain events, including the issuance of stock dividends on the Company’s common stock and, in certain instances, the issuance of the Company’s common stock or instruments convertible into the Company’s common stock at a price per share less than the exercise price of the respective warrants;

•

warrant holders may exercise the warrants through a cashless exercise if, and only if, the Company does not have an effective registration statement then available for the issuance of the shares of its common stock. If an effective registration statement is available for the issuance of its common stock, a holder may only exercise the warrants through a cash exercise;

•

the exercise price and the number and type of securities purchasable upon exercise of the warrants are subject to adjustment upon certain corporate events, including certain combinations, consolidations, liquidations, mergers, recapitalizations, reclassifications, reorganizations, stock dividends and stock splits, a sale of all or substantially all of the Company’s assets and certain other events; and

•

in the event of an extraordinary transaction (as defined in the respective warrant agreements), generally including any merger with or into another entity, sale of all or substantially all of the Company’s assets, tender offer or exchange offer, or reclassification of its common stock, in which the successor entity (as defined in the respective warrant agreements) that assumes the warrant is not a publicly traded company, the Company or any successor entity will pay the warrant holder, at such holder’s option, exercisable at any time concurrently with or within 30 days after the consummation of the extraordinary transaction, an amount of cash equal to the value of such holder’s warrants as determined in accordance with an appropriate valuation model and the terms of the respective warrant agreement.

Based on these terms, the Company has determined that the 2013 Warrants, the 2014 Warrants, the 2015 Warrants and the 2016 Warrants (together, the “Warrants”) qualify as derivatives and, as such, are presented as a derivative warrant liability on the consolidated balance sheets and recorded at fair value each reporting period. The fair value of the Warrants was estimated to be $2.7 million and $10.5 million as of December 31, 2016 and December 31, 2015, respectively. The decrease in the estimated fair value of the Warrants represents an unrealized (gain)/loss which has been recorded as a loss from the change in fair value of derivative warrant liability in the consolidated statements of operations.

During the twelve months ended December 31, 2016, Common Stock was issued as a result of exercise of Warrants as described below:

	Twelve Months Ended December 31, 2016
	Common Stock Issued		Proceeds
Series A Warrants		83,333	$	500,000
Series D Warrants		501,570		1,315,694
Series E Warrants		326,450		65,290
Series F Warrants		233,857		1,403,143
Series G Warrants		328,571		65,714
Series H Warrants		900,436		8,911,537
Series J Warrants		185,000		37,000
		2,559,217	$	12,298,378

In May 2016, as permitted by Section 2(a) of the Series H Warrant agreement, the board of directors of the Company approved a voluntary reduction of the exercise price of Series H Warrants exercisable into 375,000 shares of the Company’s common stock, from an exercise price of $15.00 per share of common stock to $6.00 per share of common stock, for the remaining term of these warrants. Except for the reduction in exercise price, the terms of these Series H Warrants remain unchanged.

In June 2016, as permitted by Section 2(a) of the Series H Warrant agreement, the Board of Directors of the Company approved a voluntary reduction of the exercise price of Series H Warrants exercisable into 150,000 shares of the Company’s common stock, from an exercise price of $15.00 per share of common stock to $8.40 per share of common stock, for the remaining term of these warrants. The board of directors of the Company also approved a voluntary reduction of the exercise price of Series H Warrants exercisable into 100,000 shares of the Company’s common stock, from an exercise price of $15.00 per share of common stock to $10.40 per share of common stock, for the remaining term of these warrants. Ultimately, the Company adjusted the exercise price to $10.40 per share of common stock for Series H Warrants exercisable into 50,000 shares of the Company’s common stock. Except for the reduction in exercise price, the terms of these Series H Warrants remain unchanged.

In June 2016, as permitted by Section 9 of the Series D Warrant agreement, the Company agreed with certain holders of the Series D Warrants to amend the exercise price and accelerate the initial exercise date for Series D Warrants exercisable into 208,370 shares of the Company’s common stock held by such holders. Pursuant to that amendment, with respect to these Series D Warrants held by those holders, the exercise price was increased from an exercise price of $2.00 per share of common stock to $3.50 per share of common stock, for the remaining term of these warrants and the initial exercise date was changed from June 11, 2016 to June 8, 2016. Except for the change in exercise price and the initial exercise date, the terms of these Series D Warrants remained unchanged.

As of December 31, 2016, all of the Series B, E, G, H, and J Series Warrants for which the exercise price had been adjusted were fully exercised or expired.

- Definition

The entire disclosure for derivative instruments and hedging activities including, but not limited to, risk management strategies, non-hedging derivative instruments, assets, liabilities, revenue and expenses, and methodologies and assumptions used in determining the amounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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Reference 8: http://www.xbrl.org/2003/role/presentationRef
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Reference 9: http://www.xbrl.org/2003/role/presentationRef
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Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 11: http://www.xbrl.org/2003/role/presentationRef
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Reference 12: http://www.xbrl.org/2003/role/presentationRef
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Reference 13: http://www.xbrl.org/2003/role/presentationRef
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Reference 14: http://www.xbrl.org/2003/role/presentationRef
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Reference 15: http://www.xbrl.org/2003/role/presentationRef
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Reference 19: http://www.xbrl.org/2003/role/presentationRef
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+ Details

Senior Secured Debt, Secured Debt and Convertible Notes

12 Months Ended

Dec. 31, 2016

Debt Disclosure [Abstract]

Senior Secured Debt, Secured Debt and Convertible Notes

8. Senior Secured Debt, Secured Debt and Convertible Notes

Senior Secured Debt

In May 2014, the Company entered into a term loan agreement (the “Loan Agreement”) with the lenders party thereto from time to time (each, a “Lender” and collectively, the “Lenders”) and Whitebox Advisors, LLC, as administrative agent for the Lenders (“Whitebox”), with a maturity date of June 23, 2017 (refer to Note 19 Subsequent Events for disclosure on our February 2017 agreement with the lender to extend the maturity date from March 15, 2017), pursuant to which the Lenders committed to provide one or more senior secured term loans to the Company in an aggregate amount of up to approximately $31.1 million on the terms and conditions set forth in the Loan Agreement (collectively, the “Term Loan”). The first advance of the Term Loan in the amount of $22.8 million (the “First Advance”), net of discounts and issue costs of $1.6 million and $1.5 million, respectively, was made to the Company in May 2014. Also in May 2014, the Company and its subsidiaries entered into an Exchange and Purchase Agreement (the “Exchange and Purchase Agreement”) with WB Gevo, Ltd. and the other Lenders party thereto from time to time and Whitebox, in its capacity as administrative agent for the Lenders. Pursuant to the terms of the Exchange and Purchase Agreement, the Lenders were given the right, subject to certain conditions, to exchange all or a portion of the outstanding principal amount of the Term Loan for the Company’s 2017 Notes (as defined below), which are convertible into shares of the Company’s common stock. While outstanding, the Term Loan bore an interest rate equal to 15% per annum, of which 5% was payable in cash and 10% was payable in kind and capitalized and added to the principal amount of the Term Loan.

In June 2014, the Lenders exchanged all $25.9 million of outstanding principal amount of Term Loan provided in the First Advance for 10% convertible senior secured notes due 2017 (the “2017 Notes” and, together with the 2022 Notes, the “Convertible Notes”), together with accrued paid-in-kind interest of $0.2 million. The terms of the 2017 Notes are set forth in an indenture by and among the Company, its subsidiaries in their capacity as guarantors, and Wilmington Savings Fund Society, FSB, as trustee (the “2017 Notes Indenture”).

The 2017 Notes were originally set to mature on March 15, 2017. However, upon the February 2017 Note Extension Transaction (see Note 19 Subsequent Events), the 2017 Notes are now set to mature on June 23, 2017. The 2017 Notes have a conversion price (the “Conversion Price”) equal to $344.83 per share or 0.0029 shares per $1 principal amount of 2017 Notes. Optional prepayment of the 2017 Notes will not be permitted. In addition, the February 2017 Note Extension amended the interest rate applicable to the 2017 Notes. The 2017 Notes now bear interest at a rate equal to 12% per annum, which is payable 6% in cash and, under certain circumstances, 6% in kind and capitalized and added to the principal amount of the 2017 Notes. While the 2017 Notes are outstanding, the Company is required to maintain an interest reserve in an amount equal to 10% of the original outstanding principal amount of $26.1 million, to be adjusted on an annual basis. As of December 31, 2016 and 2015, there was a balance of $2.6 million in the interest reserve account. This amount is classified as restricted deposits.

The 2017 Notes Indenture contains customary affirmative and negative covenants for agreements of this type and events of default, including, restrictions on disposing of certain assets, granting or otherwise allowing the imposition of a lien against certain assets, incurring certain amounts of additional indebtedness, making investments, acquiring or merging with another entity, and making dividends and other restricted payments, unless the Company receives the prior approval of the required holders. For the years ended December 31, 2016 and 2015, the Company was in compliance with the covenants. The 2017 Notes Indenture also contains limitations on the ability of the holder to assign or otherwise transfer its interest in the 2017 Notes. The 2017 Notes are secured by a lien on substantially all of the assets of the Company and is guaranteed by Agri-Energy and Gevo Development (together, the “Guarantor Subsidiaries” or “Guarantors”). On June 6, 2014, in connection with the issuance of the 2017 Notes, the Company and the Guarantor Subsidiaries entered into a Pledge and Security Agreement in favor of the collateral trustee. The collateral pledged includes substantially all of the assets of the Company and the Guarantor Subsidiaries, including intellectual property and real property. Agri-Energy has also entered into a mortgage with respect to the real property located in Luverne Minnesota.

The holders of the 2017 Notes may, at any time until the close of business on the business day immediately preceding the maturity date, convert the principal amount of the 2017 Notes, or any portion of such principal amount which is at least $1,000, into shares of the Company’s common stock. Upon conversion of the 2017 Notes, the Company will deliver shares of common stock at a conversion rate of 0.0029 shares of common stock per $1.00 principal amount of the 2017 Notes (equivalent to a conversion price of approximately $344.83 per share of common stock). Such conversion rate is subject to adjustment in certain circumstances, including in the event that there is a dividend or distribution paid on shares of the common stock or a subdivision, combination or reclassification of the common stock. The Company also has the right to increase the conversion rate (i) by any amount for a period of at least 20 business days if the Company’s board of directors determines that such increase would be in the Company’s best interest or (ii) to avoid or diminish any income tax to holders of shares of common stock or rights to purchase shares of common stock in connection with any dividend or distribution. In addition, subject to certain conditions described herein, each holder who exercises its option to voluntarily convert its 2017 Notes will receive a make-whole payment in an amount equal to any unpaid interest that would otherwise have been payable on such 2017 Notes through the maturity date (a “Voluntary Conversion Make-Whole Payment”). Subject to certain limitations, the Company may pay any Voluntary Conversion Make-Whole Payments either in cash or in shares of common stock, at its election.

The Company has the right to require holders of the 2017 Notes to convert all or part of the 2017 Notes into shares of its common stock if the last reported sales price of the common stock over any 10 consecutive trading days equals or exceeds 150% of the applicable conversion price (a “Mandatory Conversion”). Each holder whose 2017 Notes are converted in a Mandatory Conversion will receive a make-whole payment for the converted notes in an amount equal to any unpaid interest that would have otherwise been payable on such 2017 Notes through the maturity date (a “Mandatory Conversion Make-Whole Payment”). Subject to certain limitations, the Company may pay any Mandatory Conversion Make-Whole Payments either in cash or in shares of common stock, at its election. The Company did not require any holders to convert in 2014, 2015 or 2016.

If a fundamental change of the Company occurs, the holders of 2017 Notes may require the Company to repurchase all or a portion of the 2017 Notes at a cash repurchase price equal to 100% of the principal amount of such 2017 Notes, plus accrued and unpaid interest, if any, through, but excluding, the repurchase date, plus a cash make-whole payment for the repurchased 2017 Notes in an amount equal to any unpaid interest that would otherwise have been payable on such convertible 2017 Notes through the maturity date. A fundamental change includes, among other things, the Company’s common stock ceasing to be listed on a national securities exchange. See Note 19 Subsequent Events for information on the Company’s listing status.

On July 31, 2014, January 28, 2015, May 13, 2015, November 12, 2015, December 7, 2015, March 28, 2016 and September 7, 2016, we entered into amendments to the 2017 Notes Indenture to, among other things, permit the offering and issuance of additional warrants and the incurrence of indebtedness by us under such additional warrants. In connection with the November 12, 2015 amendments, we did not issue any warrants or incur any indebtedness.

On June 1, 2015, the Company entered into further amendments to the 2017 Notes Indenture to, among other things, permit (i) the execution, delivery, and performance of the FCStone Agreements (as defined below) and the related Guaranty (as defined below), (ii) the incurrence of indebtedness by the Company and Agri-Energy pursuant thereto and (iii) the making of the investments by the Company and Agri-Energy thereunder.

On August 22, 2015, the Company entered into further amendments to the 2017 Notes Indenture to, among other things, permit (i) the execution, delivery, and performance of the License Agreement (as defined below) and (ii) the exchange of all or any portion of the 2022 Notes for common stock issued by the Company.

In connection with the transactions described above, the Company also entered into a Registration Rights Agreement, dated May 9, 2014 (the “Registration Rights Agreement”), pursuant to which the Company filed a registration statement on Form S-3 registering the resale of approximately 60,000 shares of the Company’s common stock which are issuable under the 2017 Notes. This registration statement was declared effective on July 25, 2014.

The Company has elected the fair value option for accounting of the 2017 Notes in order for management to mitigate income statement volatility caused by measurement basis differences between the embedded instruments or to eliminate complexities of applying certain accounting models. Accordingly, the principal amount of 2017 Notes outstanding at December 31, 2016 of $26.1 million has been recorded at its estimated fair value of $25.8 million and is included in the 2017 Notes recorded at fair value on the consolidated balance sheets at December 31, 2016. Debt issuance costs of $1.5 million were expensed at issuance and a gain of $4.2 million has been recognized in subsequent periods in connection with the election of the fair value option. Change in the estimated fair value of the 2017 Notes represents an unrealized gain included in gain (loss) from change in fair value of 2017 Notes in the consolidated statements of operations. The fair value of the 2017 Notes at the issuance date were equal to the net proceeds from the loan. During the twelve months ended December 31, 2016, the Company incurred cash interest expense of $2.6 million related to the 2017 Notes.

The following table sets forth the inputs to the lattice model that were used to value the 2017 Notes for which the fair value option was elected.

	December 31,
	2016			2015
Stock price	$	3.40		$	12.40
Conversion Rate per $1,000		2.90			2.90
Conversion Price	$	344.83		$	344.83
Maturity date (1)	March 15, 2017			March 15, 2017
Risk-free interest rate		0.49	%		0.74	%
Estimated stock volatility		80.0	%		140.0	%
Estimated credit spread		20.0	%		30.0	%

(1)

The 2017 Notes were valued as of December 31, 2016, and used assumptions that existed at that time. The impact of our 2017 Notes Extension Transaction with the 2017 Notes holders (see Note 19 Subsequent Events) on certain key features, including extension of the maturity date to June 23, 2017 was not included in the assumptions used to value the 2017 Notes.

The following table sets forth information pertaining to the 2017 Notes which is included in the Company’s consolidated balance sheets (in thousands).

	Principal Amount of 2017 Notes		Change in Estimated Fair Value			Total
Balance - December 31, 2015	$	26,108	$	(4,543	)	$	21,565
Loss from change in fair value of debt		-	$	4,204			4,204
Balance - December 31, 2016	$	26,108	$	(339	)		25,769

Changes in certain inputs into the lattice model can have a significant impact on changes in the estimated fair value of the 2017 Notes. For example, the estimated fair value will generally decrease with: (1) a decline in the stock price; (2) decreases in the estimated stock volatility; and (3) a decrease in the estimated credit spread. The change in the estimated fair value of the 2017 Notes during the year ended December 31, 2016, represents an unrealized loss which has been recorded as a loss from change in fair value of 2017 Notes in the consolidated statements of operations.

Secured Debt

On September 30, 2016, Agri-Energy voluntarily paid off in full all outstanding amounts owed under the Amended Agri-Energy Loan Agreement and all material commitments and obligations under the Loan and Security Agreement and associated documents were terminated. As a result, at September 30, 2016, the Amended Agri-Energy Loan Agreement had a principal balance of zero. In connection with the repayment, TriplePoint Capital LLC (“TriplePoint”) terminated all of its security interests under the Amended Agri-Energy Loan Agreement (including any mortgages and membership interest pledges). In addition, the guaranties by the Company and Gevo Development of the obligations under the Amended Agri-Energy Agreement were also terminated.

The following table sets forth information pertaining to the Company’s secured debt issued to TriplePoint which is included in the Company’s consolidated balance sheets (in thousands).

	December 31,
	2016		2015
Secured debt
TriplePoint - May 2014 Advance	$	-	$	504
Total secured debt		-		504
Less:
Unamortized debt discounts and issue costs		-		(21	)
		-		483
Less current portion of debt		-		(330	)
Long-term portion of debt	$	-	$	153

Debt discounts associated with the issuance of the Company’s secured debt and convertible notes are recorded on the consolidated balance sheets as a reduction to related debt balances. The Company amortizes debt discount to interest expense over the term of the debt or expected life of the debt using the effective interest method. The unamortized debt discount at December 31, 2015 comprised a $17.0 current portion and $2.0 long-term portion. Unamortized debt issue costs totaled $2.0 (see Note 2 for more information).

Amended Agri-Energy Loan Agreement. In October 2011, the Original Agri-Energy Loan Agreement was amended and restated (the “Amended Agri-Energy Loan Agreement”) to provide Agri-Energy with additional term loan facilities of up to $15.0 million to pay a portion of the costs, expenses, and other amounts associated with the retrofit of the Agri-Energy Facility to produce isobutanol. In October 2011, Agri-Energy borrowed $10.0 million under the additional term loan facilities which originally matured in October 2015. In January 2012, Agri-Energy borrowed an additional $5.0 million under the additional term loan facilities which originally matured December 2015, bringing the total borrowed under the additional term loan facilities to $15.0 million.

May 2014 Amendments. In May 2014, the Company and its subsidiaries entered into a Consent Under and Third Amendment to Amended and Restated Plain English Growth Capital Loan and Security Agreement and Omnibus Amendment to Loan Documents (the “2014 Amendment”) pursuant to which TriplePoint amended its agreements with the Company and its subsidiaries and consented to (a) the execution, delivery, and performance of the Loan Agreement, the Exchange and Purchase Agreement, the Registration Rights Agreement, the 2017 Notes Indenture, the 2017 Notes, and the other documents related thereto (collectively the “Senior Loan Documents”); (b) the incurrence of the Term Loan with Whitebox and any other indebtedness under the Senior Loan Documents (collectively, the “Senior Indebtedness”); (c) the consummation of the exchange of the Term Loan for the 2017 Notes; (d) the offering, issuance and sale of the 2017 Notes to Whitebox and the conversion of any 2017 Notes into the common stock of the Company pursuant to the terms of the 2017 Notes Indenture; (e) the guaranty of the Senior Indebtedness provided by the Guarantors; (f) the liens granted by each of the Company and the Guarantors to secure the Senior Indebtedness and the other obligations under the Senior Loan Documents; (g) the consummation of any transactions contemplated by, and the terms of, the Senior Loan Documents by the Company and the Guarantors; and (h) the payment and performance of any of the obligations under the Senior Loan Documents by the Company and the Guarantors, including the making of dividends and distributions by the Guarantors to the Company for the purpose of enabling the Company to make any payments under the Senior Loan Documents.

As part of the 2014 Amendment, the Company repaid $9.8 million in principal payments due under the foregoing loan agreements with TriplePoint and entered into an amended loan agreement with TriplePoint. At such time, debt issuance costs were written off. At December 31, 2014, the amended loan agreement had a principal balance of $0.8 million, which amortizes over 36 months and bears interest at a rate equal to 9% per annum and matures in May 2017. There were no additional concessions or terms of the agreement which would require recognition of a gain or loss due to this amended agreement. Prior to the pay off of all outstanding amounts, Agri-Energy had granted TriplePoint a junior security interest in all of its assets as security for its obligations under the Amended Agri-Energy Loan Agreement.

On July 31, 2014, January 28, 2015, May 13, 2015, November 11, 2015, December 7, 2015, March 28, 2016 and September 7, 2016, we entered into further amendments to the Amended Agri-Energy Loan Agreement and the Gevo Security Agreement to, among other things, permit the offering and issuance of additional warrants and the incurrence of indebtedness by us under such additional warrants. In connection with the November 11, 2015 amendments, we did not issue any warrants or incur any indebtedness.

2022 Notes

The following table sets forth information pertaining to the 2022 Notes which is included in the Company’s consolidated balance sheets (in thousands). Refer to Note 19 Subsequent Events, for additional information.

	Principal Amount of 2022 Notes			Debt Discount			Debt Issue Costs			Total
Balance - December 31, 2015	$	22,400		$	(7,764	)	$	(295	)	$	14,341
Amortization of debt discount		-			4,026			-			4,026
Amortization of debt issue costs		-			-			156			156
Exchange of 2022 Notes	$	(12,825	)		-			-			(12,825	)
Write-off of debt discount and debt issue costs associated with extinguishment of debt		-			2,431			92			2,523
Balance - December 31, 2016	$	9,575		$	(1,307	)	$	(47	)	$	8,221

In July 2012, the Company sold $45.0 million in aggregate principal amount of 2022 Notes, with net proceeds of $40.9 million, after accounting for $2.7 million and $1.4 million of discounts and issue costs, respectively. The 2022 Notes bear interest at 7.5% which is to be paid semi-annually in arrears on January 1 and July 1 of each year. The 2022 Notes will mature in July 2022, unless earlier repurchased, redeemed or converted. During the years ended December 31, 2016, 2015, and 2014, the Company recorded $4.0 million, $3.7 million, and $2.8 million , respectively, of non-cash interest expense related to the amortization of debt discounts and issue costs and recorded $1.2 million, $1.8 million and $2.0 million, respectively, of cash interest expense related to the 2022 Notes. The amortization of debt issue costs and debt discounts and cash interest are included as a component of interest expense in the consolidated statements of operations. The Company amortizes debt discounts and debt issue costs associated with the 2022 Notes using an effective interest rate of 40% from the issuance date through July 2017, a five-year period, which represents the date the holders can require the Company to repurchase the 2022 Notes.

The 2022 Notes are convertible at an initial conversion rate of 0.5856 shares of the Company’s common stock per $1,000 principal amount of 2022 Notes, subject to adjustment in certain circumstances as described in the Indenture. This is equivalent to an initial conversion price of approximately $1,707.65 per share of common stock. Holders may convert the 2022 Notes at any time prior to the close of business on the third business day immediately preceding the maturity date of July 1, 2022.

If a holder elects to convert its 2022 Notes prior to July 1, 2017, such holder shall be entitled to receive, in addition to the consideration upon conversion, a Coupon Make-Whole Payment. The Coupon Make-Whole Payment is equal to the sum of the present values of the number of semi-annual interest payments that would have been payable on the 2022 Notes that a holder has elected to convert from the last day through which interest was paid up to but excluding July 1, 2017, computed using a discount rate of 2%. The Company may pay any Coupon Make-Whole Payment either in cash or in shares of common stock at its election. If the Company elects to pay in common stock, the stock will be valued at 90% of the average of the daily volume weighted average prices of the Company’s common stock for the 10 trading days preceding the date of conversion. In November 2015, we issued 55,392 shares of common stock to redeem 2,500 bonds at a face value of $1,000 per bond and reduce the liability of the 2022 Notes by $2.5 million. The net loss on the extinguishment of the 2022 Notes was $0.05 million. In February 2015, we issued 8,502 shares of common stock to convert 2,000 bonds at a face value of $1,000 per bond to reduce the liability of the 2022 Notes by $2.0 million. The net gain on the extinguishment of the 2022 Notes was $0.3 million. In September 2016, the Company issued 699,968 shares of common stock in exchange for the redemption of $11.4 million of the 2022 Notes. The net loss on the extinguishment of the 2022 Notes was $0.9 million. In December 2016, the Company issued 251,832 shares of common stock in exchange for the redemption of $1.4 million of the 2022 Notes. The net gain on the extinguishment of the 2022 Notes was $0.1 million.

If a Make-Whole Fundamental Change (as defined in the Indenture) occurs and a holder elects to convert its 2022 Notes prior to July 1, 2017, the applicable conversion rate will increase based upon reference to the table set forth in Schedule A of the Indenture. In no event will the conversion rate increase to more than 0.6734 per $1,000 principal amount of 2022 Notes.

The Company shall have a provisional redemption right (“Provisional Redemption”) to redeem, at its option, all or any part of the 2022 Notes at a price payable in cash, beginning on July 1, 2015 and prior to July 1, 2017, provided that the Company’s common stock for 20 or more trading days in a period of 30 consecutive trading days ending on the trading day immediately prior to the date of the redemption notice exceeds 150% of the conversion price in effect on such trading day. On or after July 1, 2017, the Company shall have an optional redemption right (“Optional Redemption”) to redeem, at its option, all or any part of the 2022 Notes at a price payable in cash. The price payable in cash for the Optional Redemption or Provisional Redemption is equal to 100% of the principal amount of 2022 Notes redeemed plus any accrued and unpaid interest thereon through, but excluding, the repurchase date.

If there is an Event of Default (as defined in the Indenture) under the 2022 Notes, the holders of not less than 25% in principal amount of Outstanding Notes (as defined in the Indenture) by notice to the Company and the trustee may, and the trustee at the request of such holders shall, declare the principal amount of all the Outstanding Notes and accrued and unpaid interest thereon to be due and payable immediately. There have been no events of default as of December 31, 2016.

Outstanding Obligations

The following sets forth the Company’s obligations to repay principal by year relating to the Convertible Notes at December 31, 2016 (in thousands).

	Amount
2017	$	26,108
2018		-
2019		-
2020		-
2021		-
Thereafter		9,575

Total	$	35,683

Capital Stock

12 Months Ended

Dec. 31, 2016

Stockholders Equity Note [Abstract]

Capital Stock

9. Capital Stock

As of December 31, 2016, the Company has authorized 250.0 million and 10.0 million shares of common and preferred stock, respectively. The holders of the Company’s common stock have one vote per share. The board of directors has the authority, without action by its stockholders, to designate and issue shares of preferred stock in one or more series and to fix the rights, preferences, privileges and restrictions thereof. The Company’s amended and restated certificate of incorporation provides that the Company’s board of directors will be divided into three classes, with staggered three-year terms and provides that all stockholder actions must be effected at a duly called meeting of the stockholders and not by a written consent. The amended and restated certificate of incorporation also provides that only the board of directors may call a special meeting of the stockholders and requires the approval of either a majority of the directors then in office or 66 2/3% of the voting power of all then outstanding capital stock for the adoption, amendment or repeal of any provision of the Company’s amended and restated bylaws. In addition, the amendment or repeal of certain provisions of the Company’s amended and restated certificate of incorporation requires the approval of 66 2/3% of the voting power of all then outstanding capital stock.

Common Stock Offerings

In September 2016, we issued 1,240,000 shares of common stock, 712,503 Series I Warrants and 185,000 Series J Warrants to purchase the same number of shares of our common stock. As of December 31, 2016, the Series I Warrants had an exercise price of $11.00 per share, were exercisable from the date of issuance and expire on September 13, 2021. The Series J Warrants were fully exercised in the third quarter of 2016. The gross proceeds to us were approximately $15.6 million, not including any future proceeds from the exercise of the warrants.

In June 2016, we closed a best efforts public offering of approximately 1,054,023 shares of common stock at $9.00 per share. We received gross proceeds from this offering of approximately $9.5 million.

In April 2016, we issued and sold 186,071 shares of common stock, Series F warrants to purchase an additional 514,644 shares of common stock (the “Series F Warrants”), Series G warrants to purchase an additional 328,571 shares of common stock (the “Series G Warrants”) and Series H warrants to purchase an additional 1,029,286 shares of common stock (the “Series H Warrants”). As of December 31, 2016, the Series F Warrants had an exercise price of $5.80 per share, were exercisable from the date of issuance and expire on April 1, 2021. The Series G Warrants were fully exercised in the second quarter of 2016. The Series H Warrants expired on October 1, 2016. We received gross proceeds of approximately $3.5 million, not including any future proceeds from exercise of the warrants.

In December 2015, we issued and sold 102,500 shares of common stock shares, Series D warrants to purchase an additional 502,500 shares of common stock (the “Series D Warrants”) and Series E warrants to purchase an additional 400,000 shares of common stock (the “Series E Warrants”). As of December 31, 2016, the Series D Warrants have an exercise price of $2.00 per share, are exercisable from the date of original issuance and will expire December 11, 2020. The Series E Warrants were fully exercised in the second quarter of 2016. The gross proceeds from this offering were approximately $9.97 million, not including any future proceeds from the exercise of warrants.

In May 2015, we issued and sold 215,000 shares of common stock and Series C warrants to purchase an additional 21,500 shares of common stock. The shares of common stock and the Series C Warrants were sold together as common stock units, but were immediately separable and issued separately. The Series C Warrants have an exercise price of $27.80 per share and are exercisable from the date of the original issuance and will expire on May 19, 2020. The gross proceeds from this offering were approximately $17.2 million, not including any future proceeds from the exercise of warrants.

In February 2015, we issued and sold 110,833 shares of common stock, Series A warrants to purchase an additional 110,833 shares of common stock and Series B warrants to purchase an additional 110,833 shares of common stock. The shares of common stock, the Series A Warrants and the Series B Warrants were sold together as common stock units, but were immediately separable and issued separately. As of December 31, 2016, the Series A Warrants have an exercise price of $5.80 per share, are exercisable from the date of original issuance and will expire on February 3, 2020. The Series B Warrants expired on August 3, 2015. The gross proceeds from this offering were approximately $6.7 million, not including any future proceeds from the exercise of the warrants.

In August 2014, we issued and sold 100,000 shares of common stock and warrants to purchase an additional 50,000 shares of common stock (the “2014 Warrants”) in a firm commitment underwritten public offering. The 2014 Warrants have an exercise price of $36.20 per share, are exercisable from the date of the original issuance and will expire on August 5, 2019. The gross proceeds from this offering were approximately $18.0 million, not including any future proceeds from the exercise of the 2014 Warrants.

In December 2013, we issued and sold 71,013 shares of common stock and warrants to purchase an additional 71,013 shares of common stock (the “2013 Warrants” and together with the 2014 Warrants, the Series A Warrants, the Series B Warrants, the Series C Warrants, the Series D Warrants, the Series E Warrants, the Series F warrants, the Series G Warrants, the Series H Warrants, the Series I Warrants, and the Series J Warrants, the “Warrants”) in a firm commitment underwritten public offering. The 2013 Warrants have certain anti-dilution provisions. As of December 31, 2016, the 2013 Warrants have an exercise price of $49.80, are exercisable from the date of the original issuance and will expire on December 16, 2018. This offering resulted in net proceeds of $26.4 million after deducting $2.0 million in underwriting discounts and commissions and other offering costs, not including any future proceeds from the exercise of the 2013 Warrants.

In July 2012, the Company issued 41,667 shares of its common stock, resulting in net proceeds of $57.4 million, after deducting underwriting discounts and commissions and other offering costs.

Common Stock Warrants

The following table sets forth a summary of outstanding warrants to purchase shares of the Company’s common stock as of December 31, 2016.

	Issue Date	Expiration Date	Outstanding		Exercise Price
TriplePoint Capital LLC	August 2010	August 2017		666	$	17.70
TriplePoint Capital LLC	October 2011	October 2018		523	$	17.70
TriplePoint Capital LLC	January 2012	October 2018		104	$	17.70
Genesis Select	June 2013	June 2018		100	$	24.45
2013 Warrants	December 2013	December 2018		55,774	$	49.80
2014 Warrants	August 2014	August 2019		19,462	$	36.20
Series A Warrants	February 2015	February 2020		11,417	$	5.80
Series C Warrants	May 2015	May 2020		21,500	$	27.80
Series D Warrants	December 2015	December 2020		930	$	2.00
Series E Warrants	December 2015	December 2016		-	$	-
Series F Warrants	April 2016	April 2021		280,787	$	5.80
Series G Warrants	April 2016	April 2017		-	$	-
Series H Warrants	April 2016	October 2016		-	$	-
Series I Warrants	September 2016	September 2021		712,503	$	11.00
Series J Warrants	September 2016	September 2017		-	$	-
Total				1,103,766

See Note 7 for a discussion of all Warrants issued and subsequent changes in the exercise price.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Preferred Stock
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-Publisher FASB
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+ Details

Equity Incentive Plans	12 Months Ended
Equity Incentive Plans	Dec. 31, 2016
Equity [Abstract]
Equity Incentive Plans	10. Equity Incentive Plans 2006 Omnibus Securities and Incentive Plan. During 2006, the Company established the Gevo, Inc. 2006 Omnibus Securities and Incentive Plan (the “2006 Plan”). Pursuant to the 2006 Plan, the Company granted stock awards to employees and directors of the Company. Upon adoption of the Gevo, Inc. 2010 Stock Incentive Plan (as amended, the “2010 Plan”), no further grants can be made under the 2006 Plan. At December 31, 2016, a total of 837 shares of Gevo common stock were reserved for issuance upon the exercise of outstanding stock option awards under the 2006 Plan. To the extent outstanding awards under the 2006 Plan expire, or are forfeited, cancelled, settled, or become unexercisable without the issuance of shares, the shares of common stock subject to such awards will be available for future issuance under the 2010 Plan. 2010 Stock Incentive Plan. In February 2011, the Company’s stockholders approved the 2010 Plan, which was subsequently amended in June 2013, and amended and restated in July 2015, June 2016 and November 2016, and provides for the grant of non-qualified stock options, incentive stock options, stock appreciation rights, restricted stock, restricted stock units and other equity awards to employees and directors of the Company. Stock options granted under the 2010 Plan have an exercise price that is at least equal to the fair market value of the Company’s common stock on the date the stock option is granted and expire ten years after the date of grant. At December 31, 2016, a total of 16,078 shares of Gevo common stock were reserved for issuance upon the exercise of outstanding stock option awards under the 2010 Plan, and an additional 160,873 shares were available for grant. Employee Stock Purchase Plan. In February 2011, the Company’s stockholders approved the ESPP. The offering periods for the ESPP are from January 1 to June 30 and from July 1 to December 31 of each calendar year. The Company has reserved 4,285 shares of common stock for issuance under the ESPP, of which 3,802 shares as of December 31, 2016 are available for future issuance. The purchase price of the common stock under the ESPP is 85% of the lower of the fair market value of a share of common stock on the first or last day of the purchase period.

Stock-Based Compensation

12 Months Ended

Dec. 31, 2016

Share Based Compensation [Abstract]

Stock-Based Compensation

11. Stock-Based Compensation

Stock-Based Compensation Expense. The following table sets forth the Company’s stock-based compensation expense (in thousands).

	Year Ended December 31,
	2016		2015		2014
Stock options and ESPP awards
Research and development	$	62	$	131	$	303
Selling, general and administrative		321		401		837

Restricted stock awards
Research and development		116		576		487
Selling, general and administrative		143		1,467		1,233

Restricted stock units
Research and development		28		10		-
Selling, general and administrative		216		62		-

Total stock-based compensation	$	886	$	2,647	$	2,860

Determining Fair Value of Share-Based Payment Awards. The following table sets forth the Black-Scholes option pricing model assumptions and resulting grant date fair value for stock options granted.

	Year Ended December 31,
	2016			2015			2014
Risk-free interest rate		1.49	%		1.62	%		1.74	%
Expected dividend yield	None			None			None
Expected volatility factor		106.70	%		106.89	%		71.13	%
Expected option life (in years)		5.77			5.77			5.75
Weighted average grant date fair value	$	5.66		$	35.40		$	267.00

Due to the Company’s limited history of grant activity, the expected life of options granted was estimated using the “simplified method” in accordance with SEC Staff Accounting Bulletin 110, where the expected life equals the arithmetic average of the vesting term and the original contractual term of the options. The volatility factor was determined based upon management’s estimate using inputs from comparable public companies. The risk-free interest rate assumption is determined based upon observed interest rates appropriate for the expected term of the Company’s employee stock options. The dividend yield assumption is based on the Company’s history of dividend payouts.

An annual forfeiture rate is estimated at the time of grant for all share-based payment awards, and revised, if necessary, in subsequent periods if the actual forfeiture rate differs from the Company’s estimate. Forfeitures have been estimated by the Company based upon historical and expected forfeiture experience. Estimated forfeiture rates used for the periods presented were from 0% to 5%.

Stock Option Award Activity. Stock option activity under the Company’s option plans at December 31, 2016 and changes during the year ended December 31, 2016 were as follows.

						Weighted-
						Average
				Weighted-		Remaining
				Average		Contractual
	Number of			Exercise		Term		Aggregate
	Options			Price		(years)		Intrinsic Value
Options outstanding at December 31, 2015		24,089		$	535.80			$	-
Granted		1,250			5.66
Canceled or forfeited		(8,424	)		951.23
Exercised		-			-
Options outstanding at December 31, 2016		16,915		$	289.73		7.54	$	-

Options exercisable at December 31, 2016		9,095		$	504.80		6.61	$	-

Options vested and expected to vest at December 31, 2016		16,915		$	289.73		7.54	$	-

The aggregate intrinsic values in the table above represent the total pre-tax intrinsic values (the difference between the closing price of Gevo’s common stock on the last trading day of the 2016 calendar year and the exercise price, multiplied by the number of in-the-money stock option shares) that would have been received by the option holders had all in-the-money outstanding stock options been exercised on December 31, 2016. The total intrinsic value of options exercised during the years ended December 31, 2016, 2015, and 2014 was $0.0 million.

The following table summarizes information associated with outstanding and exercisable stock options at December 31, 2016.

	Options Outstanding						Options Exercisable
					Weighted-						Weighted-
					Average				Weighted-		Average
Range of			Weighted-		Remaining				Average		Remaining
Exercise	Number of		Average Exercise		Contractual Life		Number of		Exercise		Contractual Life
Prices	Options		Price		in Years		Options		Price		in Years
$0.00 to $51.00		14,450	$	40.62		8.61		6,630	$	41.68		8.58
$105.00 to $147.00		80	$	144.90		0.32		80	$	144.90		0.32
$264.00 to $438.00		586	$	368.79		0.44		586	$	368.87		0.44
$462.00 to $1,845.00		801	$	715.51		2.31		801	$	715.51		2.31
$2,331.00 to $3,426.00		637	$	2,938.98		0.39		637	$	2,938.98		0.39
$3,801.00 to $5,742.00		361	$	4,556.47		2.26		361	$	4,556.47		2.26
		16,915						9,095

As of December 31, 2016, $0.7 million of total unrecognized compensation cost related to stock options is expected to be recognized as an expense by the Company in the future over a weighted-average period of approximately one year.

There is a maximum contractual term of 10 years for the share options. The Company settles stock option exercises with newly issued common shares. No tax benefits were realized by the Company in connection with these exercises as the Company maintains net operating loss carryforwards and has established a valuation allowance against the entire tax benefit.

Restricted Stock. The Company periodically grants restricted stock awards to employees and directors. The vesting period for restricted stock awards granted may be based upon a service period or based upon the attainment of performance objectives. The Company recognizes stock-based compensation over the vesting period, generally three to six years, for awards that vest based upon a service period. For performance based restricted stock awards, the Company recognizes expense over the requisite service period.

Non-vested restricted stock awards at December 31, 2016 and changes during the year ended December 31, 2016 were as follows.

				Weighted-
				Average
	Number of			Grant-Date
	Shares			Fair Value
Non-vested at December 31, 2015		16,413		$	54.80
Granted		-			-
Vested		(6,816	)		82.95
Canceled or forfeited		(774	)		46.16
Non-vested at December 31, 2016		8,823		$	47.51

The total fair value of restricted stock that vested during the years ended December 31, 2016, 2015 and 2014 was $1.7 million, $1.4 million, and $1.5 million , respectively. As of December 31, 2016, the total unrecognized compensation expense, net of estimated forfeitures, relating to restricted stock awards was $0.4 million, which is expected to be recognized over a weighted-average period of approximately two years.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References + Details

Gevo Development

12 Months Ended

Dec. 31, 2016

Equity [Abstract]

Gevo Development

12. Gevo Development

Gevo, Inc. currently owns 100% of the outstanding equity interests of Gevo Development.

Gevo, Inc. made capital contributions to Gevo Development of $12.3 million, $7.9 million, and $26.5 million , respectively, during the years ended December 31, 2016, 2015, and 2014.

The following table sets forth (in thousands) the net loss incurred by Gevo Development (including Agri-Energy after September 22, 2010, the closing date of the acquisition) which has been fully allocated to Gevo, Inc.’s capital contribution account based upon its capital contributions (for the period prior to September 2010) and 100% ownership (for the period after September 22, 2010).

	Year Ended December 31,
	2016			2015			2014
Gevo Development Net Loss	$	(12,983	)	$	(12,294	)	$	(14,778	)

The accounts of Agri-Energy are consolidated within Gevo Development as a wholly owned subsidiary which is then consolidated into Gevo, Inc. As of December 31, 2016, Gevo Development does not have any assets that can be used only to settle obligations of Gevo Development.

Redfield Energy, LLC	12 Months Ended
Redfield Energy, LLC	Dec. 31, 2016
Equity Method Investments And Joint Ventures [Abstract]
Redfield Energy, LLC	13. Redfield Energy, LLC In June 2011, Gevo Development entered into an isobutanol joint venture agreement (the “Joint Venture Agreement”) with Redfield Energy, LLC, a South Dakota limited liability company (“Redfield”), and executed the second amended and restated operating agreement of Redfield (together with the Joint Venture Agreement, the “Joint Venture Documents”). Under the terms of the Joint Venture Documents, Gevo Development and Redfield have agreed to work together to retrofit Redfield’s approximately 50 million gallon per year ethanol production facility located near Redfield, South Dakota (the “Redfield Facility”) for the commercial production of isobutanol. Under the terms of the Joint Venture Agreement, Redfield has issued 100 Class G membership units in Redfield (the “Class G Units”) to Gevo Development. Gevo Development is the sole holder of Class G units, which entitle Gevo Development to certain information and governance rights with respect to Redfield, including the right to appoint two members of Redfield’s 11-member board of managers. The Class G units currently carry no interest in the allocation of profits, losses or other distributions of Redfield and no voting rights. Such rights will vest upon the commencement of commercial isobutanol production at the Redfield Facility, at which time Gevo Development anticipates consolidating Redfield’s operations because Gevo anticipates it will control the activities that are most significant to the entity. Gevo Development will be responsible for all costs associated with the retrofit of the Redfield Facility. Redfield will remain responsible for certain expenses incurred by the facility including certain repair and maintenance expenses and any costs necessary to ensure that the facility is in compliance with applicable environmental laws. The Company anticipates that the Redfield Facility will continue its current ethanol production activities during much of the retrofit. Once the retrofit assets have been installed, the ethanol production operations will be suspended to enable testing of the isobutanol production capabilities of the facility (the “Performance Testing Phase”). During the Performance Testing Phase, Gevo Development will be entitled to receive all revenue generated by the Redfield Facility and will make payments to Redfield to cover the costs incurred by Redfield to operate the facility plus the profits, if any, that Redfield would have received if the facility had been producing ethanol during that period (the “Facility Payments”). Gevo Development has also agreed to maintain an escrow fund during the Performance Testing Phase as security for its obligation to make the Facility Payments. If certain conditions are met, commercial production of isobutanol at the Redfield Facility will begin upon the earlier of the date upon which certain production targets have been met or the date upon which the parties mutually agree that commercial isobutanol production at the Redfield Facility will be commercially viable at the then-current production rate. At that time, (i) Gevo Development will have the right to appoint a total of four members of Redfield’s 11-member board of managers, and (ii) the voting and economic interests of the Class G units will vest and Gevo Development, as the sole holder of the Class G Units, will be entitled to a percentage of Redfield’s profits, losses and distributions, to be calculated based upon the demonstrated isobutanol production capabilities of the Redfield Facility. Gevo Development, or one of its affiliates, will be the exclusive marketer of all products produced by the Redfield Facility once commercial production of isobutanol has begun. Additionally, Gevo, Inc. will license the technology necessary to produce isobutanol at the Redfield Facility to Redfield, subject to the continuation of the marketing arrangement described above. In the event that the isobutanol production technology fails or Redfield is permanently prohibited from using such technology, Gevo Development will forfeit the Class G Units and lose the value of its investment in Redfield. Gevo, Inc. entered into a guaranty effective as of June 2011, pursuant to which it has unconditionally and irrevocably guaranteed the payment by Gevo Development of any and all amounts owed by Gevo Development pursuant to the terms and conditions of the Joint Venture Agreement and certain other agreements that Gevo Development and Redfield expect to enter into in connection with the retrofit of the Redfield Facility. As of December 31, 2016, the Company has incurred $0.4 million in preliminary project engineering and permitting process costs for the future retrofit of the Redfield Facility which have been recorded on the Company’s consolidated balance sheets in deposits and other assets. Gevo has no obligation to Retrofit the Redfield Facility.

Income Taxes

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Income Taxes

14. Income Taxes

There is no provision for income taxes because the Company has incurred operating losses since inception. As of December 31, 2016, the Company had federal and state net operating loss carryforwards of approximately $332.1 million which may be used to offset future taxable income. The Company also had federal research and development tax credit carryforwards and other federal tax credit carryforwards which aggregate to $3.5 million at December 31, 2016. These carryforwards expire at various times through 2036 and may be limited in their annual usage by Section 382 of the Internal Revenue Code, as amended, relating to ownership changes.

The following table sets forth the tax effects of temporary differences that give rise to significant portions of the Company’s net deferred tax assets (in thousands).

	December 31,
	2016			2015			2014
Deferred tax assets:
Net operating loss carryforwards	$	133,514		$	123,647		$	115,870
Research and other credits		3,482			5,610			6,047
Other temporary differences		2,319			4,804			(2,478	)
Deferred tax assets - before valuation allowance		139,315			134,061			119,439
Valuation allowance		(139,315	)		(134,061	)		(119,439	)
Net deferred tax assets - after valuation allowance	$	-		$	-		$	-

The Company’s deferred tax assets represent an unrecognized future tax benefit. The Company recognizes uncertain tax positions net, against any operating losses or applicable research credits as they arise. Currently, there are no uncertain tax positions recognized at December 31, 2016. The Company has provided a full valuation allowance on its deferred tax assets at December 31, 2016 and 2015, as management believes it is more likely than not that the related deferred tax asset will not be realized. The reported amount of income tax expense differs from the amount that would result from applying domestic federal statutory tax rates to pretax losses, primarily because of changes in the valuation allowance.

The following table sets forth reconciling items from income tax computed at the statutory federal rate.

	Year Ended December 31,
	2016			2015			2014
Federal income tax at statutory rate		35.0	%		35.0	%		35.0	%
State income taxes, net of federal benefits		2.9	%		5.4	%		4.5	%
Research and other credits		-5.8	%		-1.2	%		-1.3	%
Permanent deductions		-18.0	%		-4.0	%		-2.2	%
Valuation allowance		-14.1	%		-35.2	%		-36.0	%

Effective tax rate		0.0	%		0.0	%		0.0	%

Accounting literature regarding liabilities for unrecognized tax benefits provides guidance for the recognition and measurement in financial statements of uncertain tax positions taken or expected to be taken in a tax return. The Company’s evaluation was performed for the tax periods from inception to December 31, 2016, which remain subject to examination by major tax jurisdictions as of December 31, 2016.

The Company may from time to time be assessed interest or penalties by major tax jurisdictions, although there have been no such assessments historically, with any material impact to its financial results. The Company would recognize interest and penalties related to unrecognized tax benefits within the income tax expense line in the accompanying consolidated statements of operations. Accrued interest and penalties would be included within the related tax liability line in the consolidated balance sheets.

Employee Benefit Plan	12 Months Ended
Employee Benefit Plan	Dec. 31, 2016
Employee Benefit Plan [Abstract]
Employee Benefit Plan	15. Employee Benefit Plan The Company’s employees participate in the Gevo, Inc. 401(k) Plan (the “401(k) Plan”). Subject to certain eligibility requirements, the 401(k) Plan covers substantially all employees after three months of service with quarterly entry dates. Employee contributions are deposited by the Company into the 401(k) Plan and may not exceed the maximum statutory contribution amount. The Company may make matching and/or discretionary contributions to the 401(k) Plan. Effective January 2013, the Company elected to cease providing an employer match.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2016

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

16. Commitments and Contingencies

Leases. During the year ended December 31, 2012, the Company entered into a six year software license agreement. The Company concluded that the software license agreement qualifies as a capital lease. Accordingly, at December 31, 2016 and 2015, the Company had capital lease liabilities of $0.1 million and $0.2 million included in accounts payable and accrued liabilities and other long-term liabilities, respectively on its consolidated balance sheet.

The Company has an operating lease for its office, research, and production facility in Englewood, Colorado (the “Colorado Facility”) with a term expiring in July 2021. The Company also maintains a corporate apartment in Colorado, which has a lease term expiring during the next 12 months.

Rent expense for the years ended December 31, 2016, 2015 and 2014 was $1.7 million, $1.6 million, and $0.5 million, respectively. The Company recognizes rent expense on its operating leases on a straight-line basis.

The table below shows the future minimum payments under non-cancelable operating leases and capital leases at December 31, 2016 (in thousands).

	Operating Leases		Capital Lease		Total Lease Payments
2017		1,543		167		1,710
2018		1,421		-		1,421
2019		907		-		907
2020		394		-		394
2021		200		-		200
Thereafter		-		-		-
Total	$	4,465	$	167	$	4,632

Indemnifications. In the ordinary course of its business, the Company makes certain indemnities under which it may be required to make payments in relation to certain transactions. As of December 31, 2016 and 2015, the Company did not have any liabilities associated with indemnities.

In addition, the Company, as permitted under Delaware law and in accordance with its amended and restated certificate of incorporation and amended and restated bylaws, indemnifies its officers and directors for certain events or occurrences, subject to certain limits, while the officer or director is or was serving at the Company’s request in such capacity. The duration of these indemnifications, commitments, and guarantees varies and, in certain cases, is indefinite. The maximum amount of potential future indemnification is unlimited; however, the Company has a director and officer insurance policy that may enable it to recover a portion of any future amounts paid. The Company accrues for losses for any known contingent liability, including those that may arise from indemnification provisions, when future payment is probable. No such losses have been recorded to date.

Environmental Liabilities. The Company’s operations are subject to environmental laws and regulations adopted by various governmental authorities in the jurisdictions in which it operates. These laws require the Company to investigate and remediate the effects of the release or disposal of materials at its locations. Accordingly, the Company has adopted policies, practices and procedures in the areas of pollution control, occupational health and the production, handling, storage and use of hazardous materials to prevent material environmental or other damage, and to limit the financial liability which could result from such events. Environmental liabilities are recorded when the Company’s liability is probable and the costs can be reasonably estimated. No environmental liabilities have been recorded as of December 31, 2016.

Fair Value Measurements and Fair Value of Financial Instruments

12 Months Ended

Dec. 31, 2016

Fair Value Disclosures [Abstract]

Fair Value Measurements and Fair Value of Financial Instruments

17. Fair Value Measurements and Fair Value of Financial Instruments

Accounting standards define fair value, outline a framework for measuring fair value, and detail the required disclosures about fair value measurements. Under these standards, fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date in the principal or most advantageous market. Standards establish a hierarchy in determining the fair market value of an asset or liability. The fair value hierarchy has three levels of inputs, both observable and unobservable. Standards require the utilization of the highest possible level of input to determine fair value.

•

Level 1 – inputs include quoted market prices in an active market for identical assets or liabilities.

•

Level 2 – inputs are market data, other than Level 1, that are observable either directly or indirectly. Level 2 inputs include quoted market prices for similar assets or liabilities, quoted market prices in an inactive market, and other observable information that can be corroborated by market data.

•

Level 3 – inputs are unobservable and corroborated by little or no market data.

These tables present the carrying value and fair value, by fair value hierarchy, of our financial instruments, excluding cash and cash equivalents, accounts receivable and accounts payable at December 31, 2016 and 2015, respectively (in thousands).

			Fair Value Measurements at December 31, 2016 (In thousands)
	Fair Value at 12/31/2016		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Recurring:
Derivative Warrant Liability	$	2,698	$	-	$	1,884	$	814
2017 Notes	$	25,769	$	-	$	-	$	25,769
Total Recurring Fair Value Measurements	$	28,467	$	-	$	1,884	$	26,583


Nonrecurring
Corn and finished goods inventory	$	1,327	$	108	$	1,219	$	-
	$	1,327	$	108	$	1,219	$	-


			Fair Value Measurements at December 31, 2015 (In thousands)
	Fair Value at 12/31/2015		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Recurring:
Derivative Warrant Liability	$	10,493	$	-	$	4,338	$	6,155
2017 Notes	$	21,565	$	-	$	-	$	21,565
Total Recurring Fair Value Measurements	$	32,058	$	-	$	4,338	$	27,720


Nonrecurring
Corn and finished goods inventory	$	1,091	$	530	$	561	$	-
	$	1,091	$	530	$	561	$	-

	Fair Value Measurements Using Significant Unobservable Inputs (Level 3) (in thousands)
	Derivative Warrant Liability			2017 Notes
Opening Balance	$	6,155		$	21,565
Transfers into Level 3		-			-
Transfers out of Level 3		-			-
Total (gains) or losses for the period		-			-
Included in earnings		2,229			4,204
Included in other comprehensive income		-			-
Purchases, issues, sales and settlements		-			-
Purchases		-			-
Issues		2,162			-
Sales		-			-
Settlements		(9,732	)		-
Closing balance	$	814		$	25,769

Fair Value Methodology

Inventories. The Company records its corn inventory at fair value only when the Company’s cost of corn purchased exceeds the market value for corn. The Company determines the market value of corn and dry distiller’s grain based upon Level 1 inputs using quoted market prices. The Company records its ethanol, isobutanol and hydrocarbon inventory at market using Level 2 inputs.

2017 Notes. The Company has estimated the fair value of the 2017 Notes to be $25.8 million and $21.6 million at December 31, 2016 and 2015, respectively, utilizing a binomial lattice model. See Note 8 for the fair value inputs used to estimate the fair value of the 2017 Notes.

2022 Notes Embedded Derivative. The Company had estimated the fair value of the embedded derivative on a stand-alone basis to be $0.0 million at December 31, 2016 and 2015, based upon Level 3 inputs. See Note 6 for the fair value inputs used to estimate the fair value of the 2022 Notes with and without the embedded derivative and the fair value of the embedded derivative.

Derivative Warrant Liability. The Company estimates the fair value the Series A and Series F warrants using a Monte-Carlo model (Level 3) while all other warrants are valued using a Black-Scholes model (Level 2).

Cash and Cash Equivalents, Accounts Receivable, Restricted Deposits and Accounts Payable. The carrying values of our cash and cash equivalents, accounts receivable, restricted deposits and accounts payable approximate their fair values due to their short maturities.

While the Company believes that its valuation methods are appropriate and consistent with other market participants, it recognizes that the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different estimate of fair value at the reporting date.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Segments

12 Months Ended

Dec. 31, 2016

Segment Reporting [Abstract]

Segments

18. Segments

We have determined that we have two operating segments: (i) Gevo, Inc. segment; and (ii) Gevo Development/Agri-Energy segment. We organize our business segments based on the nature of the products and services offered through each of our consolidated legal entities. Transactions between segments are eliminated in consolidation.

Gevo Segment. Our Gevo segment is responsible for all research and development activities related to the future production of isobutanol, including the development of our proprietary biocatalysts, the production and sale of biojet fuel, our Retrofit process and the next generation of chemicals and biofuels that will be based on our isobutanol technology. Our Gevo segment also develops, maintains and protects our intellectual property portfolio, develops future markets for our isobutanol and provides corporate oversight services.

Gevo Development/Agri-Energy Segment. Our Gevo Development/Agri-Energy segment is currently responsible for the operation of our Agri-Energy Facility and the production of ethanol, isobutanol and related products.

The Company’s chief operating decision maker is provided with and reviews the financial results of each of the Company’s consolidated legal entities, Gevo, Inc., Gevo Development, LLC, and Agri-Energy, LLC. The Company organizes its business segments based on the nature of the products and services offered through each of its consolidated legal entities. All revenue is earned, and all assets are held, in the U.S.

	Year Ended December 31,
	2016			2015			2014
Revenues:
Gevo	$	2,425		$	2,911		$	4,718
Gevo Development / Agri-Energy		24,788			27,226			23,548
Consolidated	$	27,213		$	30,137		$	28,266

Loss from operations:
Gevo	$	(11,045	)	$	(19,723	)	$	(26,567	)
Gevo Development / Agri-Energy		(12,940	)		(12,204	)		(13,210	)
Consolidated	$	(23,985	)	$	(31,927	)	$	(39,777	)

Interest expense:
Gevo	$	7,789		$	8,147		$	10,446
Gevo Development / Agri-Energy		48			96			1,578
Consolidated	$	7,837		$	8,243		$	12,024

Depreciation and amortization expense:
Gevo	$	738		$	856		$	937
Gevo Development / Agri-Energy		6,009			5,717			3,943
Consolidated	$	6,747		$	6,573		$	4,880

Acquisitions of plant, property and equipment:
Gevo	$	350		$	7		$	116
Gevo Development / Agri-Energy		5,588			1,457			4,778
Consolidated	$	5,938		$	1,464		$	4,894

	December 31,
	2016			2015
Total assets:
Gevo	$	110,072		$	100,394
Gevo Development / Agri-Energy		156,749			157,661
Intercompany eliminations (1)		(154,497	)		(155,224	)
Consolidated (2)	$	112,324		$	102,831

(1)

Includes intercompany sales of $0.2 million of hydrocarbon sales.

(2)

All other significant non-cash items relate to the activities of Gevo

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Topic 280
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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+ Details

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2016
Subsequent Events [Abstract]
Subsequent Events	19. Subsequent Events 2017 Note extension transaction. In February 2017, WB Gevo, Ltd. (“Whitebox”), the holder of our issued and outstanding 10% Convertible Senior Notes, due 2017 (the “2017 Notes”), and the Company agreed to extend the maturity date of the 2017 Notes from March 15, 2017 to June 23, 2017 (the “2017 Notes Extension Transaction”). Pursuant to the terms of a supplemental indenture, the terms of the 2017 Notes Extension Transaction include, among other things, the following: (i) an increase in the coupon on the 2017 Notes by two percent (2%) to twelve percent (12%); and (ii) the requirement that we pay down $8 million of principal on the 2017 Notes as follows: $2 million on each of March 13, 2017, April 13, 2017, May 12, 2017 and June 13, 2017, with an option for us to prepay all $8 million at any time in our sole discretion. In addition, as part of the 2017 Notes Extension Transaction, we agreed to pay Whitebox fifteen percent (15%) of the net proceeds from our next underwritten public offering, completed prior to June 23, 2017, and to be used to reduce the then-outstanding principal of the 2017 Notes, which would be in addition to the $8 million pay-down of the 2017 Notes described above. On February 23, 2017, we paid down the principal balance on the 2017 Notes by with 15% of the net proceeds from the offering referred to below, along with the $8.0 million in prepayments under the supplemental indenture, for an aggregate total payment of $9.6 million, which reduced the principal balance on the 2017 Notes to approximately $16.5 million. Issuance of common stock. In February 2017, we sold 5,680,000 Series G units, with each Series G unit consisting of one share of common stock, a Series K warrant to purchase one share of common stock and a Series M warrant to purchase one share of common stock, at a public offering price of $1.90 per Series G unit. We also agreed to sell 570,000 Series H units, with each Series H unit consisting of a pre-funded Series L warrant to purchase one share of common stock, a Series K warrant to purchase one share of common stock and a Series M warrant to purchase one share of common stock, at a public offering price of $1.89 per Series H unit. The Series K warrants will have an exercise price of $2.35 per share, be exercisable beginning the date of original issuance and will expire on February 17, 2022. The Series L warrants will have an exercise price of $1.90 per share, which will be pre-paid upon issuance, except for a nominal exercise price of $0.01 per share and, consequently, no additional payment or other consideration (other than the nominal exercise price of $0.01 per share) will be required to be delivered to us by the holder upon exercise of the Series L warrants. The Series L warrants will be exercisable from the date of original issuance and will expire on February 17, 2018. The Series M warrants will have an exercise price of $2.35 per share, be exercisable beginning on the date of original issuance and will expire on November 17, 2017. The shares of common stock and the warrants will be immediately separable and will be issued separately. The gross proceeds to us from this offering were approximately $11.9 million, not including any future proceeds from the exercise of the warrants. 2022 Note exchanges. In January 2017, we entered into private exchange agreements with holders of our 7.5% convertible 2022 Notes to exchange an aggregate of $8.4 million of principal amount of 2022 Notes for an aggregate of 2,155,382 shares of common stock. These exchanges reduced the outstanding principal amount of the 2022 Notes to $1.2 million. Reverse stock split. Effective January 5, 2017, we effected a one-for-twenty reverse split of the Company’s issued and outstanding common stock (the “Reverse Stock Split”). Upon the stock split, every twenty shares of the Company’s common stock issued and outstanding were automatically combined into one share of common stock, without any change in the par value per share. NASDAQ Compliance. In January 2017, the Company received notice from The NASDAQ Stock Market LLC that effective January 20, 2017 it had regained compliance with the NASDAQ Capital Market’s minimum bid price continued listing requirement of at least ten consecutive days with a closing bid price of its common stock in excess of $1.00.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2016

Accounting Policies [Abstract]

Nature of Business

Nature of Business. Gevo, Inc. (“Gevo” or the “Company,” which, unless otherwise indicated, refers to Gevo, Inc. and its subsidiaries) is a renewable chemicals and next generation biofuels company focused on the development and commercialization of alternatives to petroleum-based products based on isobutanol produced from renewable feedstocks. Gevo, Inc. was incorporated in Delaware on June 9, 2005. Gevo, Inc. formed Gevo Development, LLC (“Gevo Development”) in September 2009 to finance and develop biorefineries through joint venture, licensing arrangements, tolling arrangements or direct acquisition (see Note 12 Gevo Development for more information on Gevo Development). Gevo Development became a wholly-owned subsidiary of the Company in September 2010. Gevo Development purchased Agri-Energy, LLC (“Agri-Energy”) in September 2010. Through May 2012, Agri-Energy, a wholly-owned subsidiary of Gevo Development, was engaged in the business of producing and selling ethanol and related products produced at its plant located in Luverne, Minnesota (the “Agri-Energy Facility”). The Company commenced the retrofit of the Agri-Energy Facility in 2011 and commenced initial startup operations for the production of isobutanol at this facility in May 2012. In September 2012, the Company made the strategic decision to pause isobutanol production at the Agri-Energy Facility to focus on optimizing specific parts of the process to further enhance isobutanol production rates. In 2013, the Company modified the Agri-Energy Facility in order to increase the isobutanol production rate. In June 2013, the Company resumed the limited production of isobutanol, operating one fermenter and one Gevo Integrated Fermentation Technology^® (“GIFT^®”) separation system in order to (i) verify that the modifications had significantly reduced the previously identified infections, (ii) demonstrate that its biocatalyst performs in the one million liter fermenters at the Agri-Energy Facility, and (iii) confirm GIFT^® efficacy at commercial scale at the Agri-Energy Facility. In August 2013, the Company expanded production capacity at the Agri-Energy Facility by adding a second fermenter and second GIFT^® system to further verify its results with a second configuration of equipment. In October 2013, the Company began commissioning the Agri-Energy Facility on corn mash to test isobutanol production run rates and to optimize biocatalyst production, fermentation separation and water management systems. In March 2014, the Company decided to leverage the flexibility of its GIFT^® technology and make further modifications to the Agri-Energy Facility which it believed would enable the simultaneous production of isobutanol and ethanol. In July 2014, the Company began more consistent co-production of isobutanol and ethanol at the Agri-Energy Facility, with one fermenter utilized for isobutanol production and three fermenters utilized for ethanol production. In line with the Company’s strategy to maximize asset utilization and site cash flows, the Company believes that this configuration of the plant should allow it to continue to optimize its isobutanol technology at a commercial scale, while taking advantage of potentially superior ethanol contribution margins.

As of December 31, 2016, the Company continues to engage in research and development, business development, business and financial planning, optimize operations for isobutanol, hydrocarbon and ethanol production and raise capital to fund future expansion of our Agri-Energy Facility for increased isobutanol and hydrocarbon production. Ultimately, the Company believes that the attainment of profitable operations is dependent upon future events, including (i) completing its development activities resulting in commercial production and sales of isobutanol or isobutanol-derived products and/or technology, (ii) obtaining adequate financing to complete its development activities, (iii) obtaining adequate financing to build out further isobutanol production capacity, (iv) gaining market acceptance and demand for its products and services, and (v) attracting and retaining qualified personnel.

The Company has primarily derived revenue from the sale of ethanol, distiller’s grains and other related products produced as part of the ethanol production process at the Agri-Energy Facility. The production of ethanol alone is not the Company’s intended business and its future strategy is expected to depend on its ability to produce and market isobutanol and products derived from isobutanol. Given that the production of ethanol alone is not the Company’s intended business, and the Company is only beginning to achieve more consistent production and revenue from the sale of isobutanol, the historical operating results of Agri-Energy may not be indicative of future operating results for Agri-Energy or Gevo.

Financial Condition

Financial Condition. For the year ended December 31, 2016, the Company incurred a consolidated net loss of $37.2 million and had an accumulated deficit of $376.7 million. The Company’s cash and cash equivalents at December 31, 2016 totaled $27.9 million which is primarily being used for the following: (i) operating activities and completion of the side-by-side configuration of the Agri-Energy Facility; (ii) operating activities at its corporate headquarters in Colorado, including research and development work; (iii) capital improvements primarily associated with its Agri-Energy Facility; (iv) costs associated with optimizing isobutanol production technology; and (v) debt service obligations. The Company expects to incur future net losses as it continues to fund the development and commercialization of its product candidates. The Company’s transition to profitability is dependent upon, among other things, the successful development and commercialization of its product candidates and the achievement of a level of revenues adequate to support the Company’s cost structure. The Company may never achieve profitability or positive cash flows, and unless and until it does, the Company will continue to need to raise additional cash. Management intends to fund future operations through additional private and/or public offerings of debt or equity securities. In addition, the Company may seek additional capital through arrangements with strategic partners or from other sources, it may seek to restructure its secured debt and it will continue to address its cost structure. Notwithstanding, there can be no assurance that the Company will be able to raise additional funds, or achieve or sustain profitability or positive cash flows from operations. Based on the Company’s current operating plan, existing working capital at December 31, 2016 was not sufficient to meet the cash requirements to fund planned operations through the period that is one year after the date the Company’s 2016 financial statements are issued unless the Company is able to restructure and extend its debt obligations and/or raise additional capital to fund operations. These conditions raise substantial doubt about the Company’s ability to continue as a going concern at December 31, 2016. The Company’s inability to continue as a going concern may potentially affect the Company’s rights and obligations under its Senior Secured Debt and Convertible Notes. The accompanying financial statements have been prepared assuming that the Company will continue as a going concern and do not include adjustments that might result from the outcome of this uncertainty. This basis of accounting contemplates the recovery of the Company’s assets and the satisfaction of liabilities in the normal course of business. See Note 8 Senior Secured Debt, Secured Debt and Convertible Debt for information on the Company’s debt obligations.

Principles of Consolidation

Basis of Presentation

Reverse Stock Splits

Use of Estimates

Concentrations of Credit Risk

Cash and Cash Equivalents

Accounts Receivable

Inventories

Restricted Deposits

Derivative Instruments

As of December 31, 2016 and 2015, the Company did not have any forward purchase contracts or exchange-traded futures contracts.

Property, Plant and Equipment

Impairment of Property, Plant and Equipment

•

sales price of isobutanol, hydrocarbons, ethanol and by-products such as dried distiller’s grains;

•

purchase price of corn;

•

production levels of isobutanol;

•

capital and operating costs to produce isobutanol; and

•

estimated useful life of the primary asset.

Factors which can impact these assumptions include, but are not limited to;

•

effectiveness of the Company’s technology to produce isobutanol at targeted margins;

•

demand for isobutanol and oil prices; and

•

harvest levels of corn.

Debt at Fair Value Option

Research and Development

Income Taxes

Stock-Based Compensation

Net Loss Per Share

	Year Ended December 31,
	2016		2015		2014
Warrants to purchase common stock		1,103,766		1,024,635		125,212
Convertible 2017 notes		75,119		75,191		75,127
Convertible 2022 notes		5,608		13,117		15,752
Outstanding options to purchase common stock		16,915		24,089		12,245
Unvested restricted common stock		8,823		16,413		2,918
Total		1,210,231		1,153,445		231,254

The following table sets forth additional securities transactions that had they occurred in 2016 would have further diluted the calculation for earnings/ (loss) per share:


	Date	Shares
2022 Note exchanges	January 2017		2,155,382
Issuance of common stock	February 2017		5,680,000
Exercise of Series L Warrants	March 2017		155,000
Total			7,990,382

Recent Accounting Pronouncements

Adoption of New Accounting Pronouncements

Adoption of New Accounting Pronouncements.

	December 31, 2015
	As reported		As adjusted
Total Assets	$	103,128	$	102,831
Current portion of secured debt, net	$	332	$	330
2022 Notes, net	$	14,636	$	14,341

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2016

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Securities that Potentially Dilute Calculation of Diluted Earnings Per Share

	Year Ended December 31,
	2016		2015		2014
Warrants to purchase common stock		1,103,766		1,024,635		125,212
Convertible 2017 notes		75,119		75,191		75,127
Convertible 2022 notes		5,608		13,117		15,752
Outstanding options to purchase common stock		16,915		24,089		12,245
Unvested restricted common stock		8,823		16,413		2,918
Total		1,210,231		1,153,445		231,254

Additional Securities Transactions Further Diluted Calculation for Earnings (Loss) Per Share

The following table sets forth additional securities transactions that had they occurred in 2016 would have further diluted the calculation for earnings/ (loss) per share:


	Date	Shares
2022 Note exchanges	January 2017		2,155,382
Issuance of common stock	February 2017		5,680,000
Exercise of Series L Warrants	March 2017		155,000
Total			7,990,382

Schedule of New Accounting Pronouncement Early Adoption Adjustments

The adoption of this guidance had an immaterial impact on our financial position and has resulted in the following retrospective adjustments to our consolidated balance sheet at December 31, 2015 (in thousands):

	December 31, 2015
	As reported		As adjusted
Total Assets	$	103,128	$	102,831
Current portion of secured debt, net	$	332	$	330
2022 Notes, net	$	14,636	$	14,341

Inventories (Tables)

12 Months Ended

Dec. 31, 2016

Inventory Disclosure [Abstract]

Components of Inventory Balances

The following table sets forth the components of the Company’s inventory balances (in thousands).

	December 31,
	2016		2015
Raw materials
Corn	$	108	$	517
Enzymes and other inputs		309		283
Nutrients		10		4
Finished goods
Ethanol		72		172
Isobutanol		755		-
Jet Fuels, Isooctane and Isooctene		519		514
Distiller's grains		-		13
Work in process - Agri Energy		274		460
Work in process - Gevo		62		109
Spare parts		1,349		1,415
Total inventories	$	3,458	$	3,487

Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2016

Property Plant And Equipment [Abstract]

Property, Plant and Equipment by Classification

The following table sets forth the Company’s property, plant and equipment by classification (in thousands).

		December 31,
		2016			2015
Construction in progress	-	$	293		$	1,801
Plant machinery and equipment (1)	10 years		15,397			14,113
Site improvements	10 years		7,050			7,039
Agri-Energy Retrofit asset (1)	20 years		70,791			65,457
Lab equipment, furniture and fixtures and vehicles	5 years		6,431			6,389
Demonstration plant	2 years		3,597			3,597
Buildings	10 years		2,543			2,543
Computer, office equipment and software	3 years		1,594			1,566
Leasehold improvements, pilot plant, land and support equipment	2 - 5 years		2,526			2,175
Total property, plant and equipment			110,222			104,680
Less accumulated depreciation and amortization			(34,630	)		(27,903	)
Property, plant and equipment, net		$	75,592		$	76,777

(1)

In May 2016, certain assets of the Agri-Energy retrofit asset were reclassified from plant, machinery and equipment to the Agri-Energy retrofit asset.

Accounts Payable and Accrued Liabilities (Tables)

12 Months Ended

Dec. 31, 2016

Payables And Accruals [Abstract]

Components of Accounts Payable and Accrued Liabilities in Consolidated Balance Sheets

The following table sets forth the components of the Company’s accounts payable and accrued liabilities in the consolidated balance sheets (in thousands).

	December 31,
	2016		2015
Accounts payable - trade	$	2,611	$	2,691
Accrued legal-related fees		626		854
Accrued employee compensation		1,385		2,082
Accrued interest		359		840
Accrued taxes payable		136		138
Short-term capital lease		147		144
Other accrued liabilities *		929		727
Total accounts payable and accrued liabilities	$	6,193	$	7,476

*	Other accrued liabilities consist of franchise taxes, property taxes, audit fees, and a variety of other expenses, none of which individually represent greater than five percent of total current liabilities.

Derivative Warrant Liability (Tables)

12 Months Ended

Dec. 31, 2016

Derivative Instruments And Hedging Activities Disclosure [Abstract]

Schedule of Shares Issued Upon Exercise of Warrants

The following sets forth information pertaining to shares issued upon the exercise of such warrants for the year ended December 31, 2016:

	Issuance Date	Expiration Date	Exercise Price as of December 31, 2016		Shares Underlying Warrants on Issuance Date		Shares Issued upon Warrant Exercises as of December 31, 2016			Shares Underlying Warrants Outstanding as of December 31, 2016
2013 Warrants	12/16/2013	12/16/2018	$	49.80		71,013		(15,239	)		55,774
2014 Warrants	8/5/2014	8/5/2019	$	36.20		50,000		(30,538	)		19,462
Series A Warrants	2/3/2015	2/3/2020	$	5.80		110,833		(99,416	)		11,417
Series B Warrants	2/3/2015	8/3/2015		-		110,833		(96,795	)		-
Series C Warrants	5/19/2015	5/19/2020	$	27.80		21,500		-			21,500
Series D Warrants	12/11/2015	12/11/2020	$	2.00		502,500		(501,570	)		930
Series E Warrants	12/11/2015	12/11/2020		-		400,000		(400,000	)		-
Series F Warrants	4/1/2016	4/1/2021	$	5.80		514,644		(233,857	)		280,787
Series G Warrants	4/1/2016	4/1/2017		-		328,571		(328,571	)		-
Series H Warrants	4/1/2016	10/1/2016		-		1,029,286		(900,436	)		-
Series I Warrants	9/13/2016	9/13/2021	$	11.00		712,503		-			712,503
Series J Warrants	9/13/2016	9/13/2017		-		185,000		(185,000	)		-
						4,036,683		(2,791,422	)		1,102,373

Schedule of Common Stock on Warrants Exercised

During the twelve months ended December 31, 2016, Common Stock was issued as a result of exercise of Warrants as described below:

	Twelve Months Ended December 31, 2016
	Common Stock Issued		Proceeds
Series A Warrants		83,333	$	500,000
Series D Warrants		501,570		1,315,694
Series E Warrants		326,450		65,290
Series F Warrants		233,857		1,403,143
Series G Warrants		328,571		65,714
Series H Warrants		900,436		8,911,537
Series J Warrants		185,000		37,000
		2,559,217	$	12,298,378

- Definition

Tabular disclosure of warrants or rights issued. Warrants and rights outstanding are derivative securities that give the holder the right to purchase securities (usually equity) from the issuer at a specific price within a certain time frame. Warrants are often included in a new debt issue to entice investors by a higher return potential. The main difference between warrants and call options is that warrants are issued and guaranteed by the company, whereas options are exchange instruments and are not issued by the company. Also, the lifetime of a warrant is often measured in years, while the lifetime of a typical option is measured in months. Disclose the title of issue of securities called for by warrants and rights outstanding, the aggregate amount of securities called for by warrants and rights outstanding, the date from which the warrants or rights are exercisable, and the price at which the warrant or right is exercisable.

+ References + Details

Senior Secured Debt, Secured Debt and Convertible Notes (Tables)

12 Months Ended

Dec. 31, 2016

Debt Instrument [Line Items]

Inputs to Lattice Model used to Value Term Loan and 2017 Notes for which Fair Value Option was Elected

The following table sets forth the inputs to the lattice model that were used to value the 2017 Notes for which the fair value option was elected.

	December 31,
	2016			2015
Stock price	$	3.40		$	12.40
Conversion Rate per $1,000		2.90			2.90
Conversion Price	$	344.83		$	344.83
Maturity date (1)	March 15, 2017			March 15, 2017
Risk-free interest rate		0.49	%		0.74	%
Estimated stock volatility		80.0	%		140.0	%
Estimated credit spread		20.0	%		30.0	%

(1)

Information Pertaining to Convertible Notes

The following table sets forth information pertaining to the 2017 Notes which is included in the Company’s consolidated balance sheets (in thousands).

	Principal Amount of 2017 Notes		Change in Estimated Fair Value			Total
Balance - December 31, 2015	$	26,108	$	(4,543	)	$	21,565
Loss from change in fair value of debt		-	$	4,204			4,204
Balance - December 31, 2016	$	26,108	$	(339	)		25,769

Secured Debt Included in Consolidated Balance Sheets

The following table sets forth information pertaining to the Company’s secured debt issued to TriplePoint which is included in the Company’s consolidated balance sheets (in thousands).

	December 31,
	2016		2015
Secured debt
TriplePoint - May 2014 Advance	$	-	$	504
Total secured debt		-		504
Less:
Unamortized debt discounts and issue costs		-		(21	)
		-		483
Less current portion of debt		-		(330	)
Long-term portion of debt	$	-	$	153

Obligations by Year Relating to Convertible Notes

The following sets forth the Company’s obligations to repay principal by year relating to the Convertible Notes at December 31, 2016 (in thousands).

	Amount
2017	$	26,108
2018		-
2019		-
2020		-
2021		-
Thereafter		9,575

Total	$	35,683

2022 Notes

Debt Instrument [Line Items]

Information Pertaining to Convertible Notes

	Principal Amount of 2022 Notes			Debt Discount			Debt Issue Costs			Total
Balance - December 31, 2015	$	22,400		$	(7,764	)	$	(295	)	$	14,341
Amortization of debt discount		-			4,026			-			4,026
Amortization of debt issue costs		-			-			156			156
Exchange of 2022 Notes	$	(12,825	)		-			-			(12,825	)
Write-off of debt discount and debt issue costs associated with extinguishment of debt		-			2,431			92			2,523
Balance - December 31, 2016	$	9,575		$	(1,307	)	$	(47	)	$	8,221

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e),(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21538-112644

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21521-112644

+ Details

Capital Stock (Tables)

12 Months Ended

Dec. 31, 2016

Stockholders Equity Note [Abstract]

Warrants to Purchase Shares of Common Stock Outstanding

The following table sets forth a summary of outstanding warrants to purchase shares of the Company’s common stock as of December 31, 2016.

	Issue Date	Expiration Date	Outstanding		Exercise Price
TriplePoint Capital LLC	August 2010	August 2017		666	$	17.70
TriplePoint Capital LLC	October 2011	October 2018		523	$	17.70
TriplePoint Capital LLC	January 2012	October 2018		104	$	17.70
Genesis Select	June 2013	June 2018		100	$	24.45
2013 Warrants	December 2013	December 2018		55,774	$	49.80
2014 Warrants	August 2014	August 2019		19,462	$	36.20
Series A Warrants	February 2015	February 2020		11,417	$	5.80
Series C Warrants	May 2015	May 2020		21,500	$	27.80
Series D Warrants	December 2015	December 2020		930	$	2.00
Series E Warrants	December 2015	December 2016		-	$	-
Series F Warrants	April 2016	April 2021		280,787	$	5.80
Series G Warrants	April 2016	April 2017		-	$	-
Series H Warrants	April 2016	October 2016		-	$	-
Series I Warrants	September 2016	September 2021		712,503	$	11.00
Series J Warrants	September 2016	September 2017		-	$	-
Total				1,103,766

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2016

Share Based Compensation [Abstract]

Stock-Based Compensation Expense

Stock-Based Compensation Expense. The following table sets forth the Company’s stock-based compensation expense (in thousands).

	Year Ended December 31,
	2016		2015		2014
Stock options and ESPP awards
Research and development	$	62	$	131	$	303
Selling, general and administrative		321		401		837

Restricted stock awards
Research and development		116		576		487
Selling, general and administrative		143		1,467		1,233

Restricted stock units
Research and development		28		10		-
Selling, general and administrative		216		62		-

Total stock-based compensation	$	886	$	2,647	$	2,860

Weighted-Average Assumptions Used to Estimate Fair Values for Stock Options Granted Using Black-Scholes Option Pricing Model

Determining Fair Value of Share-Based Payment Awards. The following table sets forth the Black-Scholes option pricing model assumptions and resulting grant date fair value for stock options granted.

	Year Ended December 31,
	2016			2015			2014
Risk-free interest rate		1.49	%		1.62	%		1.74	%
Expected dividend yield	None			None			None
Expected volatility factor		106.70	%		106.89	%		71.13	%
Expected option life (in years)		5.77			5.77			5.75
Weighted average grant date fair value	$	5.66		$	35.40		$	267.00

Stock Option Award Activity

Stock Option Award Activity. Stock option activity under the Company’s option plans at December 31, 2016 and changes during the year ended December 31, 2016 were as follows.

						Weighted-
						Average
				Weighted-		Remaining
				Average		Contractual
	Number of			Exercise		Term		Aggregate
	Options			Price		(years)		Intrinsic Value
Options outstanding at December 31, 2015		24,089		$	535.80			$	-
Granted		1,250			5.66
Canceled or forfeited		(8,424	)		951.23
Exercised		-			-
Options outstanding at December 31, 2016		16,915		$	289.73		7.54	$	-

Options exercisable at December 31, 2016		9,095		$	504.80		6.61	$	-

Options vested and expected to vest at December 31, 2016		16,915		$	289.73		7.54	$	-

Summary of Information Associated with Outstanding and Exercisable Stock Options

The following table summarizes information associated with outstanding and exercisable stock options at December 31, 2016.

	Options Outstanding						Options Exercisable
					Weighted-						Weighted-
					Average				Weighted-		Average
Range of			Weighted-		Remaining				Average		Remaining
Exercise	Number of		Average Exercise		Contractual Life		Number of		Exercise		Contractual Life
Prices	Options		Price		in Years		Options		Price		in Years
$0.00 to $51.00		14,450	$	40.62		8.61		6,630	$	41.68		8.58
$105.00 to $147.00		80	$	144.90		0.32		80	$	144.90		0.32
$264.00 to $438.00		586	$	368.79		0.44		586	$	368.87		0.44
$462.00 to $1,845.00		801	$	715.51		2.31		801	$	715.51		2.31
$2,331.00 to $3,426.00		637	$	2,938.98		0.39		637	$	2,938.98		0.39
$3,801.00 to $5,742.00		361	$	4,556.47		2.26		361	$	4,556.47		2.26
		16,915						9,095

Non-Vested Restricted Stock Awards and Changes

Non-vested restricted stock awards at December 31, 2016 and changes during the year ended December 31, 2016 were as follows.

				Weighted-
				Average
	Number of			Grant-Date
	Shares			Fair Value
Non-vested at December 31, 2015		16,413		$	54.80
Granted		-			-
Vested		(6,816	)		82.95
Canceled or forfeited		(774	)		46.16
Non-vested at December 31, 2016		8,823		$	47.51

Gevo Development (Tables)

12 Months Ended

Dec. 31, 2016

Equity [Abstract]

Net Loss Incurred by Gevo Development

	Year Ended December 31,
	2016			2015			2014
Gevo Development Net Loss	$	(12,983	)	$	(12,294	)	$	(14,778	)

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Tax Effects of Temporary Differences that Give Rise to Net Deferred Tax Assets

The following table sets forth the tax effects of temporary differences that give rise to significant portions of the Company’s net deferred tax assets (in thousands).

	December 31,
	2016			2015			2014
Deferred tax assets:
Net operating loss carryforwards	$	133,514		$	123,647		$	115,870
Research and other credits		3,482			5,610			6,047
Other temporary differences		2,319			4,804			(2,478	)
Deferred tax assets - before valuation allowance		139,315			134,061			119,439
Valuation allowance		(139,315	)		(134,061	)		(119,439	)
Net deferred tax assets - after valuation allowance	$	-		$	-		$	-

Reconciling Items from Income Tax Computed at Statutory Federal Rate

The following table sets forth reconciling items from income tax computed at the statutory federal rate.

	Year Ended December 31,
	2016			2015			2014
Federal income tax at statutory rate		35.0	%		35.0	%		35.0	%
State income taxes, net of federal benefits		2.9	%		5.4	%		4.5	%
Research and other credits		-5.8	%		-1.2	%		-1.3	%
Permanent deductions		-18.0	%		-4.0	%		-2.2	%
Valuation allowance		-14.1	%		-35.2	%		-36.0	%

Effective tax rate		0.0	%		0.0	%		0.0	%

Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2016

Commitments And Contingencies Disclosure [Abstract]

Future Minimum Payments Under Non-cancelable Operating Leases

The table below shows the future minimum payments under non-cancelable operating leases and capital leases at December 31, 2016 (in thousands).

	Operating Leases		Capital Lease		Total Lease Payments
2017		1,543		167		1,710
2018		1,421		-		1,421
2019		907		-		907
2020		394		-		394
2021		200		-		200
Thereafter		-		-		-
Total	$	4,465	$	167	$	4,632

Fair Value Measurements and Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2016

Fair Value Disclosures [Abstract]

Schedule of Carrying Value and Fair Value by Fair Value Hierarchy of Financial Instruments

			Fair Value Measurements at December 31, 2016 (In thousands)
	Fair Value at 12/31/2016		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Recurring:
Derivative Warrant Liability	$	2,698	$	-	$	1,884	$	814
2017 Notes	$	25,769	$	-	$	-	$	25,769
Total Recurring Fair Value Measurements	$	28,467	$	-	$	1,884	$	26,583


Nonrecurring
Corn and finished goods inventory	$	1,327	$	108	$	1,219	$	-
	$	1,327	$	108	$	1,219	$	-


			Fair Value Measurements at December 31, 2015 (In thousands)
	Fair Value at 12/31/2015		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Recurring:
Derivative Warrant Liability	$	10,493	$	-	$	4,338	$	6,155
2017 Notes	$	21,565	$	-	$	-	$	21,565
Total Recurring Fair Value Measurements	$	32,058	$	-	$	4,338	$	27,720


Nonrecurring
Corn and finished goods inventory	$	1,091	$	530	$	561	$	-
	$	1,091	$	530	$	561	$	-

Schedule of Fair Value Measurements Using Significant Unobservable Inputs (Level 3)

	Fair Value Measurements Using Significant Unobservable Inputs (Level 3) (in thousands)
	Derivative Warrant Liability			2017 Notes
Opening Balance	$	6,155		$	21,565
Transfers into Level 3		-			-
Transfers out of Level 3		-			-
Total (gains) or losses for the period		-			-
Included in earnings		2,229			4,204
Included in other comprehensive income		-			-
Purchases, issues, sales and settlements		-			-
Purchases		-			-
Issues		2,162			-
Sales		-			-
Settlements		(9,732	)		-
Closing balance	$	814		$	25,769

- Definition

Tabular disclosure of financial instruments measured at fair value, including those classified in shareholders' equity measured on a recurring or nonrecurring basis. Disclosures include, but are not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. Nonrecurring fair value measurements are those that are required or permitted in the statement of financial position in particular circumstances.

+ References + Details

Segments (Tables)

12 Months Ended

Dec. 31, 2016

Segment Reporting [Abstract]

Summary of Segment Information

	Year Ended December 31,
	2016			2015			2014
Revenues:
Gevo	$	2,425		$	2,911		$	4,718
Gevo Development / Agri-Energy		24,788			27,226			23,548
Consolidated	$	27,213		$	30,137		$	28,266

Loss from operations:
Gevo	$	(11,045	)	$	(19,723	)	$	(26,567	)
Gevo Development / Agri-Energy		(12,940	)		(12,204	)		(13,210	)
Consolidated	$	(23,985	)	$	(31,927	)	$	(39,777	)

Interest expense:
Gevo	$	7,789		$	8,147		$	10,446
Gevo Development / Agri-Energy		48			96			1,578
Consolidated	$	7,837		$	8,243		$	12,024

Depreciation and amortization expense:
Gevo	$	738		$	856		$	937
Gevo Development / Agri-Energy		6,009			5,717			3,943
Consolidated	$	6,747		$	6,573		$	4,880

Acquisitions of plant, property and equipment:
Gevo	$	350		$	7		$	116
Gevo Development / Agri-Energy		5,588			1,457			4,778
Consolidated	$	5,938		$	1,464		$	4,894

	December 31,
	2016			2015
Total assets:
Gevo	$	110,072		$	100,394
Gevo Development / Agri-Energy		156,749			157,661
Intercompany eliminations (1)		(154,497	)		(155,224	)
Consolidated (2)	$	112,324		$	102,831

(1)

Includes intercompany sales of $0.2 million of hydrocarbon sales.

(2)

All other significant non-cash items relate to the activities of Gevo

Nature of Business and Financial Condition - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accounting Policies [Abstract]
Net loss	$ (37,228)	$ (36,194)	$ (41,145)
Accumulated deficit	(376,720)	(339,492)
Cash and cash equivalents	$ 27,888	$ 17,031	$ 6,359	$ 24,625

Summary Significant Accounting Policies - Additional Information (Detail)			12 Months Ended
	Dec. 14, 2016 $ / shares	Apr. 15, 2015	Dec. 31, 2016 USD ($) Customer $ / shares	Dec. 31, 2015 USD ($) Customer $ / shares	Dec. 31, 2014 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Common stock, par value \| $ / shares	$ 0.01		$ 0.01	$ 0.01
Reverse split of common stock	one-for-twenty	one-for-fifteen
Reverse stock split ratio	0.05	0.067
Allowance for doubtful accounts			$ 0	$ 0
Restricted Deposits			10.00%
Restricted deposits			$ 2,611,000	2,611,000
Selling, general and administrative expense			8,965,000	16,692,000	$ 18,341,000
Deferred tax assets, Valuation Allowance			139,315,000	134,061,000	119,439,000
Future minimum operating lease obligations			4,465,000
ASU 2015-17
Summary Of Significant Accounting Policies [Line Items]
Net deferred income taxes			0
Patents
Summary Of Significant Accounting Policies [Line Items]
Selling, general and administrative expense			$ 200,000	$ 900,000	$ 900,000
Customer Concentration Risk \| Accounts Receivable \| C&N Ethanol Marketing, LLC
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage			53.00%	56.00%
Number of customer \| Customer			1	1
Customer Concentration Risk \| Consolidated Revenue \| C&N Ethanol Marketing, LLC
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage			75.00%	73.00%	71.00%
Customer Concentration Risk \| Consolidated Revenue \| Land O' Lakes Purina Feed LLC
Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage			18.00%	19.00%	13.00%

Securities that Potentially Dilute Calculation of Diluted Earnings Per Share (Detail) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Warrants to purchase common stock	1,210,231	1,153,445	231,254
Warrants to purchase common stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Warrants to purchase common stock	1,103,766	1,024,635	125,212
Convertible 2017 Notes
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Warrants to purchase common stock	75,119	75,191	75,127
2022 Notes
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Warrants to purchase common stock	5,608	13,117	15,752
Outstanding options to purchase common stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Warrants to purchase common stock	16,915	24,089	12,245
Unvested restricted common stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Warrants to purchase common stock	8,823	16,413	2,918

Additional Securities Transactions would have Further Diluted Calculation for Earnings (Loss) Per Share (Detail) - shares	1 Months Ended			3 Months Ended	12 Months Ended
	Mar. 31, 2017	Feb. 28, 2017	Jan. 31, 2017	Mar. 30, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Securities that could potentially dilute the calculation of diluted earnings per share					1,210,231	1,153,445	231,254
Subsequent Event
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Securities that could potentially dilute the calculation of diluted earnings per share				7,990,382
2022 Notes exchanges \| Subsequent Event
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Securities that could potentially dilute the calculation of diluted earnings per share			2,155,382
Issuance of common stock \| Subsequent Event
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Securities that could potentially dilute the calculation of diluted earnings per share		5,680,000
Exercise of Series L Warrants \| Scenario, Forecast
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Securities that could potentially dilute the calculation of diluted earnings per share	155,000

Schedule of New Accounting Pronouncement Early Adoption Adjustments (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Total Assets	$ 112,324	$ 102,831
Current portion of secured debt, net		330
2022 Notes, net	$ 8,221	14,341
As reported
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Total Assets		103,128
Current portion of secured debt, net		332
2022 Notes, net		$ 14,636

Components of Inventory Balances (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Inventory [Line Items]
Spare parts	$ 1,349	$ 1,415
Total inventories	3,458	3,487
Corn
Inventory [Line Items]
Raw materials	108	517
Enzymes And Other Inputs
Inventory [Line Items]
Raw materials	309	283
Nutrients
Inventory [Line Items]
Raw materials	10	4
Ethanol
Inventory [Line Items]
Finished goods	72	172
Isobutanol
Inventory [Line Items]
Finished goods	755
Jet Fuels Isooctane And Isooctene
Inventory [Line Items]
Finished goods	519	514
Distiller's grains
Inventory [Line Items]
Finished goods		13
Agri-Energy
Inventory [Line Items]
Work in process	274	460
Gevo
Inventory [Line Items]
Work in process	$ 62	$ 109

Property, Plant and Equipment by Classification (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Property Plant And Equipment [Line Items]
Total property, plant and equipment	$ 110,222	$ 104,680
Less accumulated depreciation and amortization	(34,630)	(27,903)
Property, plant and equipment, net	75,592	76,777
Construction in progress
Property Plant And Equipment [Line Items]
Total property, plant and equipment	$ 293	1,801
Plant machinery and equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful life	10 years
Total property, plant and equipment	$ 15,397	14,113
Site improvements
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful life	10 years
Total property, plant and equipment	$ 7,050	7,039
Agri-Energy Retrofit asset
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful life	20 years
Total property, plant and equipment	$ 70,791	65,457
Lab equipment, furniture and fixtures and vehicles
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful life	5 years
Total property, plant and equipment	$ 6,431	6,389
Demonstration plant
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful life	2 years
Total property, plant and equipment	$ 3,597	3,597
Buildings
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful life	10 years
Total property, plant and equipment	$ 2,543	2,543
Computer, office equipment and software
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Total property, plant and equipment	$ 1,594	1,566
Leasehold improvements, pilot plant, land and support equipment
Property Plant And Equipment [Line Items]
Total property, plant and equipment	$ 2,526	$ 2,175
Leasehold improvements, pilot plant, land and support equipment \| Minimum
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful life	2 years
Leasehold improvements, pilot plant, land and support equipment \| Maximum
Property Plant And Equipment [Line Items]
Property, plant and equipment, useful life	5 years

Property, Plant and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property Plant And Equipment [Line Items]
Amortization of capital lease asset	$ 100	$ 100	$ 100
Depreciation and amortization	6,747	6,573	4,880
Depreciation expense in cost of goods sold	6,000	5,700	$ 4,000
Computer, office equipment and software
Property Plant And Equipment [Line Items]
Capital lease	$ 700	$ 700

Components Accounts Payable and Accrued Liabilities in Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Payables And Accruals [Abstract]
Accounts payable - trade	$ 2,611	$ 2,691
Accrued legal-related fees	626	854
Accrued employee compensation	1,385	2,082
Accrued interest	359	840
Accrued taxes payable	136	138
Short-term capital lease	147	144
Other accrued liabilities	929	727
Total accounts payable and accrued liabilities	$ 6,193	$ 7,476

Embedded Derivatives - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	Jul. 31, 2012	Dec. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Estimated fair value of the embedded derivatives		$ 0	$ 0
2022 Notes
Derivative [Line Items]
Percentage of convertible senior notes embedded derivatives	7.50%
7.5% convertible senior notes, maturity date	2022
2022 notes, conversion date	Jul. 01, 2017	Jul. 01, 2017

Derivative Warrant Liability - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended								12 Months Ended
	Dec. 11, 2015	Sep. 30, 2016	Jun. 30, 2016	Apr. 30, 2016	Dec. 31, 2015	May 31, 2015	Feb. 28, 2015	Aug. 31, 2014	Dec. 31, 2013	Dec. 31, 2016	May 31, 2016	Apr. 01, 2016
Derivative [Line Items]
Additional purchase of common stock shares										4,036,683
Derivative warrant liability fair value					$ 10,493					$ 2,698
Series A
Derivative [Line Items]
Additional purchase of common stock shares							110,833			110,833
Warrant , exercise price										$ 5.80
Series B
Derivative [Line Items]
Additional purchase of common stock shares							110,833			110,833
Series C
Derivative [Line Items]
Additional purchase of common stock shares						21,500				21,500
Warrant , exercise price										$ 27.80
Series D
Derivative [Line Items]
Additional purchase of common stock shares					502,500					502,500
Warrant , exercise price										$ 2.00
Series E
Derivative [Line Items]
Additional purchase of common stock shares					400,000					400,000
Series F
Derivative [Line Items]
Additional purchase of common stock shares				514,644						514,644
Number of securities called by each warrant				1
Warrant , exercise price										$ 5.80
Series H
Derivative [Line Items]
Additional purchase of common stock shares				1,029,286						1,029,286
Number of securities called by each warrant				1
Series G
Derivative [Line Items]
Additional purchase of common stock shares				328,571						328,571
Number of securities called by each warrant				1
Series I
Derivative [Line Items]
Additional purchase of common stock shares		712,503								712,503
Number of securities called by each warrant		1
Warrant , exercise price										$ 11.00
Series J
Derivative [Line Items]
Additional purchase of common stock shares		185,000								185,000
Number of securities called by each warrant		1
375,000 Exercisable Series H
Derivative [Line Items]
Shares warrants exercisable											375,000
Warrant , exercise price				$ 15.00							$ 6.00
150,000 Exercisable Series H
Derivative [Line Items]
Shares warrants exercisable			150,000
Warrant , exercise price			$ 8.40									$ 15.00
100,000 Exercisable Series H
Derivative [Line Items]
Shares warrants exercisable			100,000
Warrant , exercise price			$ 10.40									$ 15.00
50,000 Exercisable Series H
Derivative [Line Items]
Shares warrants exercisable			50,000
Warrant , exercise price			$ 10.40
Series D Warrant Agreement Amendment
Derivative [Line Items]
Shares warrants exercisable			208,370
Warrant , exercise price	$ 2.00		$ 3.50
Warrants, exercise date	Jun. 11, 2016		Jun. 08, 2016
2013 Warrants
Derivative [Line Items]
Additional purchase of common stock shares									71,013	71,013
Warrant , exercise price										$ 49.80
2014 Warrants
Derivative [Line Items]
Additional purchase of common stock shares								50,000		50,000
Warrant , exercise price								$ 36.20		$ 36.20

Schedule of Shares Issued Upon Exercise of Warrants (Detail) - $ / shares	1 Months Ended							12 Months Ended
	Sep. 30, 2016	Apr. 30, 2016	Dec. 31, 2015	May 31, 2015	Feb. 28, 2015	Aug. 31, 2014	Dec. 31, 2013	Dec. 31, 2016
Derivative [Line Items]
Additional purchase of common stock shares								4,036,683
Shares Issued upon Warrant Exercises								(2,791,422)
Shares Underlying Warrants Outstanding								1,102,373
Series A
Derivative [Line Items]
Warrant, Issuance Date								Feb. 03, 2015
Warrants, Expiration date								Feb. 03, 2020
Warrant , Exercise Price								$ 5.80
Additional purchase of common stock shares					110,833			110,833
Shares Issued upon Warrant Exercises								(99,416)
Shares Underlying Warrants Outstanding								11,417
Series B
Derivative [Line Items]
Warrant, Issuance Date								Feb. 03, 2015
Warrants, Expiration date								Aug. 03, 2015
Additional purchase of common stock shares					110,833			110,833
Shares Issued upon Warrant Exercises								(96,795)
Series C
Derivative [Line Items]
Warrant, Issuance Date								May 19, 2015
Warrants, Expiration date								May 19, 2020
Warrant , Exercise Price								$ 27.80
Additional purchase of common stock shares				21,500				21,500
Shares Underlying Warrants Outstanding								21,500
Series D
Derivative [Line Items]
Warrant, Issuance Date								Dec. 11, 2015
Warrants, Expiration date								Dec. 11, 2020
Warrant , Exercise Price								$ 2.00
Additional purchase of common stock shares			502,500					502,500
Shares Issued upon Warrant Exercises								(501,570)
Shares Underlying Warrants Outstanding								930
Series E
Derivative [Line Items]
Warrant, Issuance Date								Dec. 11, 2015
Warrants, Expiration date								Dec. 11, 2020
Additional purchase of common stock shares			400,000					400,000
Shares Issued upon Warrant Exercises								(400,000)
Series F
Derivative [Line Items]
Warrant, Issuance Date								Apr. 01, 2016
Warrants, Expiration date								Apr. 01, 2021
Warrant , Exercise Price								$ 5.80
Additional purchase of common stock shares		514,644						514,644
Shares Issued upon Warrant Exercises								(233,857)
Shares Underlying Warrants Outstanding								280,787
Series G
Derivative [Line Items]
Warrant, Issuance Date								Apr. 01, 2016
Warrants, Expiration date								Apr. 01, 2017
Additional purchase of common stock shares		328,571						328,571
Shares Issued upon Warrant Exercises								(328,571)
Series H
Derivative [Line Items]
Warrant, Issuance Date								Apr. 01, 2016
Warrants, Expiration date								Oct. 01, 2016
Additional purchase of common stock shares		1,029,286						1,029,286
Shares Issued upon Warrant Exercises								(900,436)
Series I
Derivative [Line Items]
Warrant, Issuance Date								Sep. 13, 2016
Warrants, Expiration date								Sep. 13, 2021
Warrant , Exercise Price								$ 11.00
Additional purchase of common stock shares	712,503							712,503
Shares Underlying Warrants Outstanding								712,503
Series J
Derivative [Line Items]
Warrant, Issuance Date								Sep. 13, 2016
Warrants, Expiration date								Sep. 13, 2017
Additional purchase of common stock shares	185,000							185,000
Shares Issued upon Warrant Exercises								(185,000)
2013 Warrants
Derivative [Line Items]
Warrant, Issuance Date								Dec. 16, 2013
Warrants, Expiration date								Dec. 16, 2018
Warrant , Exercise Price								$ 49.80
Additional purchase of common stock shares							71,013	71,013
Shares Issued upon Warrant Exercises								(15,239)
Shares Underlying Warrants Outstanding								55,774
2014 Warrants
Derivative [Line Items]
Warrant, Issuance Date								Aug. 05, 2014
Warrants, Expiration date								Aug. 05, 2019
Warrant , Exercise Price						$ 36.20		$ 36.20
Additional purchase of common stock shares						50,000		50,000
Shares Issued upon Warrant Exercises								(30,538)
Shares Underlying Warrants Outstanding								19,462

Schedule of Common Stock on Warrants Exercised (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Class Of Warrant Or Right [Line Items]
Class of warrants exercised during period \| shares	2,559,217
Proceeds from the exercise of warrants	$ 12,298,378	$ 10,166,000
Series A
Class Of Warrant Or Right [Line Items]
Class of warrants exercised during period \| shares	83,333
Proceeds from the exercise of warrants	$ 500,000
Series D
Class Of Warrant Or Right [Line Items]
Class of warrants exercised during period \| shares	501,570
Proceeds from the exercise of warrants	$ 1,315,694
Series E
Class Of Warrant Or Right [Line Items]
Class of warrants exercised during period \| shares	326,450
Proceeds from the exercise of warrants	$ 65,290
Series F
Class Of Warrant Or Right [Line Items]
Class of warrants exercised during period \| shares	233,857
Proceeds from the exercise of warrants	$ 1,403,143
Series G
Class Of Warrant Or Right [Line Items]
Class of warrants exercised during period \| shares	328,571
Proceeds from the exercise of warrants	$ 65,714
Series H
Class Of Warrant Or Right [Line Items]
Class of warrants exercised during period \| shares	900,436
Proceeds from the exercise of warrants	$ 8,911,537
Series J
Class Of Warrant Or Right [Line Items]
Class of warrants exercised during period \| shares	185,000
Proceeds from the exercise of warrants	$ 37,000

Senior Secured Debt, Secured Debt and Convertible Notes - Additional Information (Detail)	1 Months Ended							12 Months Ended
	Feb. 28, 2017 USD ($)	Dec. 31, 2016 USD ($) $ / shares shares	Sep. 30, 2016 USD ($) shares	Nov. 30, 2015 USD ($) Bond shares	Feb. 28, 2015 USD ($) Bond shares	Jun. 30, 2014 USD ($) $ / shares	Jul. 31, 2012 USD ($)	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($)	Jan. 31, 2017 USD ($) shares	Mar. 27, 2015 USD ($)	May 31, 2014 USD ($)	Jan. 31, 2012 USD ($)	Oct. 31, 2011 USD ($)
Debt Instrument [Line Items]
Aggregate principal amount outstanding						10.00%
Restricted deposits		$ 2,611,000						$ 2,611,000	$ 2,611,000
Common stock, shares authorized \| shares		250,000,000						250,000,000	250,000,000
Estimated fair value of principal amount									$ 21,565,000
Interest expense								$ 7,837,000	8,243,000	$ 8,255,000
Secured debt									504,000
Unamortized debt discount, current portion									17,000
Unamortized debt discount, long-term portion									2,000
Unamortized debt issue costs									2,000
Debt Instrument, repurchase amount		$ 15,000,000						15,000,000						$ 5,000,000	$ 10,000,000
Debt instrument, periodic payment, principal								$ 9,800,000
Long term borrowing interest rate		9.00%						9.00%
Amortization period of debt issuance cost								36 months
Proceeds from issuance of convertible debt, net										25,907,000
Non-cash interest expense								$ 3,977,000	$ 3,772,000	7,860,000
Common stock shares issued \| shares		7,074,246						7,074,246	1,080,352
Convertible 2017 Notes
Debt Instrument [Line Items]
Debt instrument maturity date								Mar. 15, 2017	Mar. 15, 2017
Debt issuance cost		$ 1,500,000						$ 1,500,000				$ 4,200,000
Conversion Price \| $ / shares		$ 344.83				$ 344.83		$ 344.83
Debt Conversion, Description								The 2017 Notes have a conversion price (the “Conversion Price”) equal to $344.83 per share or 0.0029 shares per $1 principal amount of 2017 Notes.
Conversion Rate								0.0029
Debt instrument, face amount		$ 26,100,000						$ 26,100,000
Debt instrument, convertible, conversion price		$ 1,000						$ 1,000
Number of consecutive trading days required for redemption								10 days
Excess to percentage of conversion price								150.00%
Common stock, shares authorized \| shares		60,000						60,000
Estimated fair value of principal amount		$ 25,769,000						$ 25,769,000	$ 21,565,000
Interest expense								2,600,000
Aggregate principal amount on sale of convertible notes		$ 26,108,000						$ 26,108,000	26,108,000
Convertible 2017 Notes \| Change In Accounting Method Accounted For As Change In Estimate
Debt Instrument [Line Items]
Percentage repurchase price								100.00%
Convertible 2017 Notes \| Whitebox
Debt Instrument [Line Items]
Debt instrument maturity date								Mar. 15, 2017
2022 Notes
Debt Instrument [Line Items]
Debt instrument maturity date								Jul. 01, 2022
Debt issuance cost							$ 1,400,000
Debt instrument, interest rate							7.50%
Conversion Price \| $ / shares		$ 1,707.65						$ 1,707.65
Conversion Rate								0.5856
Debt instrument, convertible, conversion price		$ 1,000						$ 1,000
Interest expense								$ 1,200,000	1,800,000	2,000,000
Amortization period of debt issuance cost								5 years
Aggregate principal amount on sale of convertible notes							$ 45,000,000
Proceeds from issuance of convertible debt, net							40,900,000
Discount on sale of convertible notes							$ 2,700,000
Non-cash interest expense								$ 4,000,000	$ 3,700,000	2,800,000
Debt discounts and debt issue costs amortization rate								40.00%
Amortization period of debt discount								5 years
2022 notes, conversion date							Jul. 01, 2017	Jul. 01, 2017
Discount rate used in computation of interest payment								2.00%
Convertible senior secured note, percentage of stock price								90.00%
Number of trading days for valuation								10 days
Common stock shares issued \| shares		251,832	699,968	55,392	8,502			251,832
Number of bonds redeemed \| Bond				2,500	2,000
Face value of each bond redeemed				$ 1,000	$ 1,000
Redemption of debt instrument		$ 1,400,000	$ 11,400,000	2,500,000	2,000,000
Net gain (loss) on extinguishment of debt instrument		$ 100,000	(900,000)	$ (50,000)	$ 300,000
Required principal amount in percentage								25.00%
First Installment
Debt Instrument [Line Items]
Aggregate outstanding principal amount of term loan						$ 25,900,000
Make-Whole Fundamental Change \| 2022 Notes \| Maximum
Debt Instrument [Line Items]
Conversion Rate								0.6734
Provisional Redemption \| 2022 Notes
Debt Instrument [Line Items]
Number of consecutive trading days required for redemption								30 days
Excess to percentage of conversion price								150.00%
Number of trading days required for redemption								20 or more trading days
Term Loans
Debt Instrument [Line Items]
Debt instrument, interest rate		12.00%						12.00%					15.00%
Term Loans \| Interest Payable In Cash
Debt Instrument [Line Items]
Debt instrument, interest rate		6.00%						6.00%					5.00%
Term Loans \| Interest Payable In Kind
Debt Instrument [Line Items]
Debt instrument, interest rate		6.00%						6.00%					10.00%
Term Loans \| First Installment
Debt Instrument [Line Items]
Accrued paid in kind interest						$ 200,000
Amended Agri-Energy Loan Agreement
Debt Instrument [Line Items]
Secured debt			$ 0
Debt instrument, additional term loan															$ 15,000,000
Loan Agreement
Debt Instrument [Line Items]
Debt instrument maturity date								Mar. 15, 2017
Loan Agreement \| Term Loans
Debt Instrument [Line Items]
Line of credit, maximum borrowing capacity													$ 31,100,000
Loan Agreement \| Term Loans \| First Installment
Debt Instrument [Line Items]
Line Of Credit Facility Current Borrowing Capacity													22,800,000
Debt, discount													1,600,000
Debt issuance cost													$ 1,500,000
2014 Amendments
Debt Instrument [Line Items]
Debt instrument maturity date								May 31, 2017
Secured debt										$ 800,000
Subsequent Event \| Convertible 2017 Notes \| Whitebox
Debt Instrument [Line Items]
Debt instrument maturity date	Jun. 23, 2017
Subsequent Event \| 2022 Notes
Debt Instrument [Line Items]
Aggregate principal amount on sale of convertible notes											$ 8,400,000
Common stock shares issued \| shares											2,155,382
Subsequent Event \| First Installment \| Convertible 2017 Notes \| Whitebox
Debt Instrument [Line Items]
Debt instrument, periodic payment, principal	$ 2,000,000
Subsequent Event \| Loan Agreement
Debt Instrument [Line Items]
Debt instrument maturity date	Jun. 23, 2017

Schedule of Estimated Fair Value Assumption of 2017 Notes (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2016
Debt Instrument [Line Items]
Stock price			$ 9.00
Convertible 2017 Notes
Debt Instrument [Line Items]
Stock price	$ 3.40	$ 12.40
Conversion Rate per $1,000	2.90	2.90
Conversion Price	$ 344.83	$ 344.83
Maturity date	Mar. 15, 2017	Mar. 15, 2017
Risk-free interest rate	0.49%	0.74%
Estimated stock volatility	80.00%	140.00%
Estimated credit spread	20.00%	30.00%

Schedule of Estimated Fair Value Assumption of 2017 Notes (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2016
2017 Notes Extension Transaction
Debt Instrument [Line Items]
Debt instrument maturity date	Jun. 23, 2017

Information Pertaining to 2017 Notes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Beginning Balance	$ 21,565
Loss/(Gain) from the change in fair value of 2017 Notes	4,204	$ (3,895)	$ (648)
Ending Balance		21,565
2017 Notes
Debt Instrument [Line Items]
Principal Amount of 2017 Notes	26,108	26,108
Change in Estimated Fair Value, Beginning Balance	(4,543)
Loss from change in fair value of debt	4,204
Change in Estimated Fair Value, Ending Balance	(339)	(4,543)
Beginning Balance	21,565
Loss/(Gain) from the change in fair value of 2017 Notes	4,204
Ending Balance	$ 25,769	$ 21,565

Secured Debt Included in Consolidated Balance Sheets (Detail) $ in Thousands	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Secured debt	$ 504
Less: Unamortized debt discounts and issue costs	(21)
Secured debt, net	483
Less current portion of debt	(330)
Long-term portion of debt	153
TriplePoint Capital LLC \| TriplePoint - May 2014 Advance
Debt Instrument [Line Items]
Secured debt	$ 504

Information Pertaining to 2022 Notes (Detail)	12 Months Ended
Information Pertaining to 2022 Notes (Detail)	Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Beginning balance	$ 14,341,000
Beginning balance	(2,000)
Ending balance	8,221,000
2022 Notes
Debt Instrument [Line Items]
Beginning balance	14,341,000
Amortization of debt discount	4,026,000
Amortization of debt issue costs	156,000
Exchange of 2022 Notes	(12,825,000)
Write-off of debt discount and debt issue costs associated with extinguishment of debt	2,523,000
Ending balance	8,221,000
2022 Notes \| Principal Amount of 2022 Notes
Debt Instrument [Line Items]
Beginning balance	22,400,000
Exchange of 2022 Notes	(12,825,000)
Ending balance	9,575,000
2022 Notes \| Debt Discount
Debt Instrument [Line Items]
Beginning balance	(7,764,000)
Amortization of debt discount	4,026,000
Write-off of debt discount and debt issue costs associated with extinguishment of debt	2,431,000
Ending balance	(1,307,000)
2022 Notes \| Debt Issue Costs
Debt Instrument [Line Items]
Beginning balance	(295,000)
Amortization of debt issue costs	156,000
Write-off of debt discount and debt issue costs associated with extinguishment of debt	92,000
Ending balance	$ (47,000)

Obligations by Year Relating to Convertible Notes (Detail) $ in Thousands	Dec. 31, 2016 USD ($)
Disclosure Obligations By Year Relating To Convertible Notes [Abstract]
2017	$ 26,108
Thereafter	9,575
Total	$ 35,683

Capital Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended									12 Months Ended
	Sep. 30, 2016	Jun. 30, 2016	Apr. 30, 2016	Dec. 31, 2015	May 31, 2015	Feb. 28, 2015	Aug. 31, 2014	Dec. 31, 2013	Jul. 31, 2012	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stockholders Equity [Line Items]
Common stock, shares authorized				250,000,000						250,000,000	250,000,000
Preferred stock, shares authorized										10,000,000
Common stock, voting rights										The holders of the Company’s common stock have one vote per share.
Voting power required for amendment or repeal of any provisions										66.67%
Common stock shares issued and sold	1,240,000	1,054,023	186,071	102,500			100,000	71,013	41,667
Proceeds from issuance of common stock and common stock warrants	$ 15,600	$ 9,500	$ 3,500	$ 9,970	$ 17,200	$ 6,700	$ 18,000		$ 57,400	$ 28,661	$ 33,820	$ 18,000
Stock price		$ 9.00
Additional purchase of common stock shares										4,036,683
Common stock units issued					215,000	110,833
Net proceeds from common stock issued								$ 26,400
Underwriting discounts commissions and other offering costs								$ 2,000
2014 Warrants
Stockholders Equity [Line Items]
Warrants, exercise price							$ 36.20			$ 36.20
Warrants, Expiration date										Aug. 05, 2019
Additional purchase of common stock shares							50,000			50,000
2013 Warrants
Stockholders Equity [Line Items]
Warrants, exercise price										$ 49.80
Warrants, Expiration date										Dec. 16, 2018
Additional purchase of common stock shares								71,013		71,013
Series I Warrant
Stockholders Equity [Line Items]
Warrants issued to purchase same number of common stock	712,503
Warrants, exercise price										$ 11.00
Warrants, Expiration date										Sep. 13, 2021
Series J Warrant
Stockholders Equity [Line Items]
Warrants issued to purchase same number of common stock	185,000
Series F Warrant
Stockholders Equity [Line Items]
Warrants, exercise price										$ 5.80
Warrants, Expiration date										Apr. 01, 2021
Additional purchase of common stock shares			514,644
Series G Warrant
Stockholders Equity [Line Items]
Additional purchase of common stock shares			328,571
Series H Warrant
Stockholders Equity [Line Items]
Warrants, Expiration date										Oct. 01, 2016
Additional purchase of common stock shares			1,029,286
Series D Warrant
Stockholders Equity [Line Items]
Warrants, exercise price										$ 2.00
Warrants, Expiration date										Dec. 11, 2020
Additional purchase of common stock shares				502,500
Series E Warrant
Stockholders Equity [Line Items]
Additional purchase of common stock shares				400,000
Series C Warrant
Stockholders Equity [Line Items]
Warrants, exercise price					$ 27.80
Warrants, Expiration date										May 19, 2020
Additional purchase of common stock shares					21,500
Series A Warrant
Stockholders Equity [Line Items]
Warrants, exercise price										$ 5.80
Warrants, Expiration date										Feb. 03, 2020
Additional purchase of common stock shares						110,833
Series B Warrant
Stockholders Equity [Line Items]
Warrants, Expiration date										Aug. 03, 2015
Additional purchase of common stock shares						110,833

Warrants to Purchase Shares of Common Stock Outstanding (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2016	Aug. 31, 2014
Class Of Warrant Or Right [Line Items]
Warrants, Outstanding	1,103,766
Series A
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Feb. 03, 2015
Warrants, Expiration Date	Feb. 03, 2020
Warrants, Outstanding	11,417
Warrant , Exercise Price	$ 5.80
Series C
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	May 19, 2015
Warrants, Expiration Date	May 19, 2020
Warrants, Outstanding	21,500
Warrant , Exercise Price	$ 27.80
Series D
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Dec. 11, 2015
Warrants, Expiration Date	Dec. 11, 2020
Warrants, Outstanding	930
Warrant , Exercise Price	$ 2.00
Series E
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Dec. 11, 2015
Warrants, Expiration Date	Dec. 31, 2016
Series F
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Apr. 01, 2016
Warrants, Expiration Date	Apr. 01, 2021
Warrants, Outstanding	280,787
Warrant , Exercise Price	$ 5.80
Series G
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Apr. 01, 2016
Warrants, Expiration Date	Apr. 01, 2017
Series H
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Apr. 01, 2016
Warrants, Expiration Date	Oct. 01, 2016
Series I
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Sep. 13, 2016
Warrants, Expiration Date	Sep. 13, 2021
Warrants, Outstanding	712,503
Warrant , Exercise Price	$ 11.00
Series J
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Sep. 13, 2016
Warrants, Expiration Date	Sep. 13, 2017
2013 Warrants
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Dec. 16, 2013
Warrants, Expiration Date	Dec. 16, 2018
Warrants, Outstanding	55,774
Warrant , Exercise Price	$ 49.80
2014 Warrants
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Aug. 05, 2014
Warrants, Expiration Date	Aug. 05, 2019
Warrants, Outstanding	19,462
Warrant , Exercise Price	$ 36.20	$ 36.20
TriplePoint Capital LLC \| Warrant 1
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Aug. 31, 2010
Warrants, Expiration Date	Aug. 31, 2017
Warrants, Outstanding	666
Warrant , Exercise Price	$ 17.70
TriplePoint Capital LLC \| Warrant 2
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Oct. 31, 2011
Warrants, Expiration Date	Oct. 31, 2018
Warrants, Outstanding	523
Warrant , Exercise Price	$ 17.70
TriplePoint Capital LLC \| Warrant 3
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Jan. 31, 2012
Warrants, Expiration Date	Oct. 31, 2018
Warrants, Outstanding	104
Warrant , Exercise Price	$ 17.70
Genesis Select
Class Of Warrant Or Right [Line Items]
Warrant, Issuance Date	Jun. 30, 2013
Warrants, Expiration Date	Jun. 30, 2018
Warrants, Outstanding	100
Warrant , Exercise Price	$ 24.45

Equity Incentive Plans - Additional Information (Detail) - shares	1 Months Ended	12 Months Ended
	Feb. 28, 2011	Dec. 31, 2016
Omnibus Securities and Incentive Plan 2006
Equity Incentive Plan [Line Items]
Common stock reserved for issuance		837
Stock Incentive Plan 2010
Equity Incentive Plan [Line Items]
Common stock reserved for issuance		16,078
Stock option grant, expiry period from grant date	10 years
Common stock, available for grant		160,873
Employee Stock Purchase Plan
Equity Incentive Plan [Line Items]
Common stock reserved for issuance		4,285
Common stock, available for grant		3,802
Share price as percentage of fair market value		85.00%

Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	$ 886	$ 2,647	$ 2,860
Stock options and ESPP awards \| Research and Development Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	62	131	303
Stock options and ESPP awards \| Selling, General and Administrative Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	321	401	837
Unvested restricted common stock \| Research and Development Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	116	576	487
Unvested restricted common stock \| Selling, General and Administrative Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	143	1,467	$ 1,233
Restricted stock units \| Research and Development Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	28	10
Restricted stock units \| Selling, General and Administrative Expense
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	$ 216	$ 62

Weighted-Average Assumptions Used to Estimate Fair Values for Stock Options Granted Using Black-Scholes Option Pricing Model (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Risk-free interest rate	1.49%	1.62%	1.74%
Expected dividend yield	0.00%	0.00%	0.00%
Expected volatility factor	106.70%	106.89%	71.13%
Expected option life (in years)	5 years 9 months 7 days	5 years 9 months 7 days	5 years 9 months
Weighted average grant date fair value	$ 5.66	$ 35.40	$ 267.00

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option, estimated forfeiture rate	0.00%
Stock option, estimated forfeiture rate	5.00%
Total intrinsic value of options exercised	$ 0.0	$ 0.0	$ 0.0
Unrecognized compensation cost	$ 0.7
Unrecognized compensation cost, recognition period	1 year
Maximum contractual term for options	10 years
Unvested restricted common stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost	$ 0.4
Unrecognized compensation cost, recognition period	2 years
Fair Value of Restricted Stock Vested	$ 1.7	$ 1.4	$ 1.5
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock awards vesting period	3 years
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock awards vesting period	6 years

Stock Option Award Activity (Detail)	12 Months Ended
Stock Option Award Activity (Detail)	Dec. 31, 2016 $ / shares shares
Number of options
Options outstanding at beginning of year \| shares	24,089
Granted \| shares	1,250
Canceled or forfeited \| shares	(8,424)
Options outstanding at end of year \| shares	16,915
Options exercisable \| shares	9,095
Options vested and expected to vest \| shares	16,915
Weighted Average Exercise Price
Options outstanding at beginning of year \| $ / shares	$ 535.80
Granted \| $ / shares	5.66
Canceled or forfeited \| $ / shares	951.23
Options outstanding at end of year \| $ / shares	289.73
Options exercisable \| $ / shares	504.80
Options vested and expected to vest \| $ / shares	$ 289.73
WEIGHTED AVERAGE REMAINING CONTRACTUAL TERM
Options outstanding	7 years 6 months 15 days
Options exercisable	6 years 7 months 10 days
Options vested and expected to vest	7 years 6 months 15 days

Summary of Information Associated with Outstanding and Exercisable Stock Options (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Options Outstanding, Number of Options	16,915	24,089
Options Outstanding, Weighted- Average Exercise Price	$ 289.73	$ 535.80
Options Outstanding, Weighted- Average Remaining Contractual Life in Years	7 years 6 months 15 days
Options Exercisable, Number of Options	9,095
Options Exercisable, Weighted- Average Exercise Price	$ 504.80
Options Exercisable, Weighted- Average Remaining Contractual Life in Years	6 years 7 months 10 days
Range One
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Range	$ 0.00
Range of Exercise Prices, Upper Range	$ 51.00
Options Outstanding, Number of Options	14,450
Options Outstanding, Weighted- Average Exercise Price	$ 40.62
Options Outstanding, Weighted- Average Remaining Contractual Life in Years	8 years 7 months 10 days
Options Exercisable, Number of Options	6,630
Options Exercisable, Weighted- Average Exercise Price	$ 41.68
Options Exercisable, Weighted- Average Remaining Contractual Life in Years	8 years 6 months 29 days
Range Two
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Range	$ 105.00
Range of Exercise Prices, Upper Range	$ 147.00
Options Outstanding, Number of Options	80
Options Outstanding, Weighted- Average Exercise Price	$ 144.90
Options Outstanding, Weighted- Average Remaining Contractual Life in Years	3 months 26 days
Options Exercisable, Number of Options	80
Options Exercisable, Weighted- Average Exercise Price	$ 144.90
Options Exercisable, Weighted- Average Remaining Contractual Life in Years	3 months 26 days
Range Three
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Range	$ 264.00
Range of Exercise Prices, Upper Range	$ 438.00
Options Outstanding, Number of Options	586
Options Outstanding, Weighted- Average Exercise Price	$ 368.79
Options Outstanding, Weighted- Average Remaining Contractual Life in Years	5 months 9 days
Options Exercisable, Number of Options	586
Options Exercisable, Weighted- Average Exercise Price	$ 368.87
Options Exercisable, Weighted- Average Remaining Contractual Life in Years	5 months 9 days
Range Four
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Range	$ 462.00
Range of Exercise Prices, Upper Range	$ 1,845.00
Options Outstanding, Number of Options	801
Options Outstanding, Weighted- Average Exercise Price	$ 715.51
Options Outstanding, Weighted- Average Remaining Contractual Life in Years	2 years 3 months 22 days
Options Exercisable, Number of Options	801
Options Exercisable, Weighted- Average Exercise Price	$ 715.51
Options Exercisable, Weighted- Average Remaining Contractual Life in Years	2 years 3 months 22 days
Range Five
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Range	$ 2,331.00
Range of Exercise Prices, Upper Range	$ 3,426.00
Options Outstanding, Number of Options	637
Options Outstanding, Weighted- Average Exercise Price	$ 2,938.98
Options Outstanding, Weighted- Average Remaining Contractual Life in Years	4 months 21 days
Options Exercisable, Number of Options	637
Options Exercisable, Weighted- Average Exercise Price	$ 2,938.98
Options Exercisable, Weighted- Average Remaining Contractual Life in Years	4 months 21 days
Range Six
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Range	$ 3,801.00
Range of Exercise Prices, Upper Range	$ 5,742.00
Options Outstanding, Number of Options	361
Options Outstanding, Weighted- Average Exercise Price	$ 4,556.47
Options Outstanding, Weighted- Average Remaining Contractual Life in Years	2 years 3 months 4 days
Options Exercisable, Number of Options	361
Options Exercisable, Weighted- Average Exercise Price	$ 4,556.47
Options Exercisable, Weighted- Average Remaining Contractual Life in Years	2 years 3 months 4 days

Non-Vested Restricted Stock Awards and Changes Period (Detail) - Unvested restricted common stock	12 Months Ended
	Dec. 31, 2016 $ / shares shares
Number of shares
Non-vested at December 31, 2015 \| shares	16,413
Vested \| shares	(6,816)
Canceled or forfeited \| shares	(774)
Non-vested at December 31, 2016 \| shares	8,823
Weighted-Average Grant-Date Fair Value
Non-vested at December 31, 2015 \| $ / shares	$ 54.80
Vested \| $ / shares	82.95
Canceled or forfeited \| $ / shares	46.16
Non-vested at December 31, 2016 \| $ / shares	$ 47.51

Gevo Development - Additional Information (Detail) - Gevo Development - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class Of Stock [Line Items]
Equity ownership of wholly owned subsidiary	100.00%
Capital contribution to subsidiaries	$ 12.3	$ 7.9	$ 26.5

Net Loss Incurred by Gevo Development (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Gevo Development
Related Party Transaction [Line Items]
Gevo Development Net Loss	$ (12,983)	$ (12,294)	$ (14,778)

Redfield Energy, LLC - Additional Information (Detail) - Redfield Boe in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2016 USD ($) Boe Person shares
Related Party Transaction [Line Items]
Redfield ethanol production facility \| Boe	50
Limited partners capital account units issued \| shares	100
Members in board of managers \| Person	11
Cost for retrofit of Redfield Facilities \| $	$ 0.4

Income Taxes - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($)
Income Taxes [Line Items]
Net operating loss carry forwards expiration	2036
Uncertain tax positions recognized	$ 0
Federal And State
Income Taxes [Line Items]
Net operating loss carryforwards	332,100
Federal Research And Development \| Federal Tax
Income Taxes [Line Items]
Net operating loss carryforwards	$ 3,500

Tax Effects of Temporary Differences that Give Rise to Net Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Net operating loss carryforwards	$ 133,514	$ 123,647	$ 115,870
Research and other credits	3,482	5,610	6,047
Other temporary differences	2,319	4,804	(2,478)
Deferred tax assets - before valuation allowance	139,315	134,061	119,439
Valuation allowance	$ (139,315)	$ (134,061)	$ (119,439)

Reconciling Items from Income Tax Computed at Statutory Federal Rate (Detail)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Components Of Income Tax Expense Benefit Continuing Operations [Abstract]
Federal income tax at statutory rate	35.00%	35.00%	35.00%
State income taxes, net of federal benefits	2.90%	5.40%	4.50%
Research and other credits	(5.80%)	(1.20%)	(1.30%)
Permanent deductions	(18.00%)	(4.00%)	(2.20%)
Valuation allowance	(14.10%)	(35.20%)	(36.00%)
Effective tax rate	0.00%	0.00%	0.00%

Employee Benefit Plan - Additional Information (Detail)	12 Months Ended
Employee Benefit Plan - Additional Information (Detail)	Dec. 31, 2016
Employee Benefit Plan [Abstract]
Eligibility requirement service period as per the 401(k) plan	3 months

Commitments and Contingencies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Commitments And Contingencies [Line Items]
Capital lease obligation included in other non-current liabilities	$ 147,000	$ 144,000
Operating lease expiration period	2021-07
Corporate apartment lease term expiring period	12 months
Operating leases rent expense	$ 1,700,000	1,600,000	$ 500,000
Environmental liabilities	0
Accounts Payable and Accrued Liabilities
Schedule Of Commitments And Contingencies [Line Items]
Capital lease liabilities	100,000	100,000
Other Long-term Liabilities
Schedule Of Commitments And Contingencies [Line Items]
Capital lease obligation included in other non-current liabilities	$ 200,000	$ 200,000
Software License Arrangement
Schedule Of Commitments And Contingencies [Line Items]
Capital lease agreement	6 years

Future Minimum Payments Under Non-Cancelable Operating Leases (Detail) $ in Thousands	Dec. 31, 2016 USD ($)
Disclosure Future Minimum Payments Under Non Cancelable Operating Leases [Abstract]
Operating Leases, 2017	$ 1,543
Operating Leases, 2018	1,421
Operating Leases, 2019	907
Operating Leases, 2020	394
Operating Leases, 2021	200
Operating Leases, Total	4,465
Capital Lease, 2017	167
Capital Lease, Total	167
Total Lease Payments, 2017	1,710
Total Lease Payments, 2018	1,421
Total Lease Payments, 2019	907
Total Lease Payments, 2020	394
Total Lease Payments, 2021	200
Total Lease Payments, Total	$ 4,632

Schedule of Carrying Value and Fair Value by Fair Value Hierarchy of Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Measurements, Recurring
Recurring:
Total Recurring Fair Value Measurements	$ 28,467	$ 32,058
Fair Value, Measurements, Recurring \| Derivative Warrant Liability
Recurring:
Total Recurring Fair Value Measurements	2,698	10,493
Fair Value, Measurements, Recurring \| 2017 Notes
Recurring:
Total Recurring Fair Value Measurements	25,769	21,565
Fair Value, Measurements, Nonrecurring
Nonrecurring
Total Nonrecurring Fair Value Measurements	1,327	1,091
Fair Value, Measurements, Nonrecurring \| Corn and Finished Goods Inventory
Nonrecurring
Total Nonrecurring Fair Value Measurements	1,327	1,091
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Nonrecurring
Nonrecurring
Total Nonrecurring Fair Value Measurements	108	530
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Nonrecurring \| Corn and Finished Goods Inventory
Nonrecurring
Total Nonrecurring Fair Value Measurements	108	530
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Recurring:
Total Recurring Fair Value Measurements	1,884	4,338
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring \| Derivative Warrant Liability
Recurring:
Total Recurring Fair Value Measurements	1,884	4,338
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Nonrecurring
Nonrecurring
Total Nonrecurring Fair Value Measurements	1,219	561
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Nonrecurring \| Corn and Finished Goods Inventory
Nonrecurring
Total Nonrecurring Fair Value Measurements	1,219	561
Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Recurring:
Total Recurring Fair Value Measurements	26,583	27,720
Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring \| Derivative Warrant Liability
Recurring:
Total Recurring Fair Value Measurements	814	6,155
Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring \| 2017 Notes
Recurring:
Total Recurring Fair Value Measurements	$ 25,769	$ 21,565

Schedule of Fair Value Measurements Using Significant Unobservable Inputs (Level 3) (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($)
Derivative Warrant Liability
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Opening Balance	$ 6,155
Included in earnings	2,229
Purchases, issues, sales and settlements
Issues	2,162
Settlements	(9,732)
Closing balance	814
2017 Notes
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Opening Balance	21,565
Included in earnings	4,204
Purchases, issues, sales and settlements
Closing balance	$ 25,769

Fair Value Measurements and Fair Value of Financial Instruments - Additional Information (Detail) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated fair value of principal amount		$ 21,565,000
Estimated fair value of the embedded derivatives	$ 0	0
2017 Notes
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated fair value of principal amount	25,769,000	21,565,000
2022 Notes \| Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated fair value of the embedded derivatives	$ 0	$ 0

Segments - Additional Information (Detail)	12 Months Ended
Segments - Additional Information (Detail)	Dec. 31, 2016 Segment
Segment Reporting [Abstract]
Number of operating segments	2

Information on Business Segments (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Revenues	$ 27,213	$ 30,137	$ 28,266
Loss from operations	(23,985)	(31,927)	(39,777)
Interest expense	7,837	8,243	12,024
Depreciation and amortization expense	6,747	6,573	4,880
Acquisitions of plant, property and equipment	5,938	1,464	4,894
Total assets	112,324	102,831
Intercompany Eliminations
Segment Reporting Information [Line Items]
Total assets	(154,497)	(155,224)
Gevo
Segment Reporting Information [Line Items]
Revenues	2,425	2,911	4,718
Loss from operations	(11,045)	(19,723)	(26,567)
Interest expense	7,789	8,147	10,446
Depreciation and amortization expense	738	856	937
Acquisitions of plant, property and equipment	350	7	116
Gevo \| Operating Segments
Segment Reporting Information [Line Items]
Total assets	110,072	100,394
Gevo Development / Agri-Energy
Segment Reporting Information [Line Items]
Revenues	24,788	27,226	23,548
Loss from operations	(12,940)	(12,204)	(13,210)
Interest expense	48	96	1,578
Depreciation and amortization expense	6,009	5,717	3,943
Acquisitions of plant, property and equipment	5,588	1,457	$ 4,778
Gevo Development / Agri-Energy \| Operating Segments
Segment Reporting Information [Line Items]
Total assets	$ 156,749	$ 157,661

Information on Business Segments (Parenthetical) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting [Abstract]
Intercompany sales	$ 0.2	$ 0.2

Subsequent Events - Additional Information (Detail) $ / shares in Units, $ in Thousands				1 Months Ended										12 Months Ended
	Jan. 05, 2017	Dec. 14, 2016	Apr. 15, 2015	Feb. 28, 2017 USD ($) $ / shares shares	Jan. 31, 2017 USD ($) $ / shares shares	Sep. 30, 2016 USD ($) shares	Jun. 30, 2016 USD ($)	Apr. 30, 2016 USD ($) shares	Dec. 31, 2015 USD ($) shares	May 31, 2015 USD ($) shares	Feb. 28, 2015 USD ($) shares	Aug. 31, 2014 USD ($)	Jul. 31, 2012 USD ($)	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($)	Feb. 23, 2017 USD ($)	Nov. 30, 2015 shares
Subsequent Event [Line Items]
Debt instrument, periodic payment, principal														$ 9,800
Outstanding principal amount									$ 14,341					8,221	$ 14,341
Common stock units issued \| shares										215,000	110,833
Proceeds from issuance of common stock and common stock warrants						$ 15,600	$ 9,500	$ 3,500	$ 9,970	$ 17,200	$ 6,700	$ 18,000	$ 57,400	$ 28,661	$ 33,820	$ 18,000
Common stock shares issued \| shares									1,080,352					7,074,246	1,080,352
Reverse split of common stock		one-for-twenty	one-for-fifteen
Reverse stock split ratio		0.05	0.067
NASDAQ listing minimum bid price requirement description														In January 2017, the Company received notice from The NASDAQ Stock Market LLC that effective January 20, 2017 it had regained compliance with the NASDAQ Capital Market’s minimum bid price continued listing requirement of at least ten consecutive days with a closing bid price of its common stock in excess of $1.00.
Series G
Subsequent Event [Line Items]
Number of securities called by each warrant \| shares								1
Warrants, expiration date														Apr. 01, 2017
Series H
Subsequent Event [Line Items]
Number of securities called by each warrant \| shares								1
Warrants, expiration date														Oct. 01, 2016
Subsequent Event
Subsequent Event [Line Items]
Proceeds from issuance of common stock and common stock warrants				$ 11,900
Reverse split of common stock	one-for-twenty
Reverse stock split ratio	0.05
Regain compliance with listing qualifications initial period date					Jan. 20, 2017
Regain compliance with listing qualifications minimum number of consecutive business period					10 days
Regain compliance with listing qualifications common stock minimum bid price \| $ / shares					$ 1.00
Subsequent Event \| Series K Warrant
Subsequent Event [Line Items]
Warrant , exercise price \| $ / shares				$ 2.35
Warrants, expiration date				Feb. 17, 2022
Subsequent Event \| Series M Warrant
Subsequent Event [Line Items]
Warrant , exercise price \| $ / shares				$ 2.35
Warrants, expiration date				Nov. 17, 2017
Subsequent Event \| Series L Warrant
Subsequent Event [Line Items]
Warrant , exercise price \| $ / shares				$ 0.01
Warrants, expiration date				Feb. 17, 2018
Warrant, exercise price aggregate \| $ / shares				$ 1.90
Subsequent Event \| Series G
Subsequent Event [Line Items]
Common stock units issued \| shares				5,680,000
Number of securities called by each warrant \| shares				1
Public offering price per share \| $ / shares				$ 1.90
Subsequent Event \| Series G \| Series K Warrant
Subsequent Event [Line Items]
Number of securities called by each warrant \| shares				1
Subsequent Event \| Series G \| Series M Warrant
Subsequent Event [Line Items]
Number of securities called by each warrant \| shares				1
Subsequent Event \| Series H
Subsequent Event [Line Items]
Common stock units issued \| shares				570,000
Public offering price per share \| $ / shares				$ 1.89
Subsequent Event \| Series H \| Series K Warrant
Subsequent Event [Line Items]
Number of securities called by each warrant \| shares				1
Subsequent Event \| Series H \| Series M Warrant
Subsequent Event [Line Items]
Number of securities called by each warrant \| shares				1
Subsequent Event \| Series H \| Series L Warrant
Subsequent Event [Line Items]
Number of securities called by each warrant \| shares				1
Convertible 2017 Notes
Subsequent Event [Line Items]
Debt instrument maturity date														Mar. 15, 2017	Mar. 15, 2017
Aggregate principal amount on sale of convertible notes									$ 26,108					$ 26,108	$ 26,108
2022 Notes
Subsequent Event [Line Items]
Debt instrument maturity date														Jul. 01, 2022
Percentage of convertible senior notes													7.50%
10% convertible senior notes, maturity date													2022
Outstanding principal amount									$ 14,341					$ 8,221	$ 14,341
Aggregate principal amount on sale of convertible notes													$ 45,000
Common stock shares issued \| shares						699,968					8,502			251,832				55,392
2022 Notes \| Subsequent Event
Subsequent Event [Line Items]
Percentage of convertible senior notes					7.50%
Aggregate principal amount on sale of convertible notes					$ 8,400
Common stock shares issued \| shares					2,155,382
2022 Notes \| Subsequent Event \| Principal Amount of Convertible Notes
Subsequent Event [Line Items]
Outstanding principal amount					$ 1,200
Whitebox \| Convertible 2017 Notes
Subsequent Event [Line Items]
Debt instrument maturity date														Mar. 15, 2017
Debt instrument coupon rate														2.00%
Whitebox \| Convertible 2017 Notes \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument maturity date				Jun. 23, 2017
Percentage of convertible senior notes				10.00%
10% convertible senior notes, maturity date				2017
Debt instrument coupon rate				12.00%
Repayments of debt				$ 8,000
Percentage of net proceeds from underwritten public offering for repayment of debt																	15.00%
Aggregate total principal payment																	$ 9,600
Outstanding principal amount																	$ 16,500
Whitebox \| Convertible 2017 Notes \| First Installment \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument, periodic payment, principal				2,000
Whitebox \| Convertible 2017 Notes \| April 13, 2017 \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument, periodic payment, principal				2,000
Whitebox \| Convertible 2017 Notes \| May 12, 2017 \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument, periodic payment, principal				2,000
Whitebox \| Convertible 2017 Notes \| June 13, 2017 \| Subsequent Event
Subsequent Event [Line Items]
Debt instrument, periodic payment, principal				$ 2,000