Renewable Energy (REGI) 10-K 14 Mar 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Feb. 29, 2016	Jun. 30, 2015
Document and Entity Information [Abstract]
Entity Registrant Name	Renewable Energy Group, Inc.
Entity Central Index Key	1,463,258
Document Type	10-K
Document Period End Date	Dec. 31, 2015
Amendment Flag	false
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Public Float			$ 468,186
Entity Common Stock, Shares Outstanding (in shares)		43,837,714

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
CURRENT ASSETS:
Cash and cash equivalents	$ 47,081	$ 63,516
Marketable securities	0	16,770
Accounts receivable, net (includes amounts owed by related parties of $0 and $36, respectively)	310,731	294,669
Inventories	85,890	97,508
Prepaid expenses and other assets	31,882	43,135
Restricted cash	0	12,845
Total current assets	475,584	528,443
Property, plant and equipment, net	574,584	493,196
Goodwill	16,080	188,275
Intangible assets, net	30,941	28,837
Investments	8,797	9,736
Other assets	11,819	14,434
Restricted cash	105,815	104,815
TOTAL ASSETS	1,223,620	1,367,736
CURRENT LIABILITIES:
Revolving line of credit	23,149	16,679
Current maturities of long-term debt	5,206	5,746
Accounts payable (includes amounts owed to related parties of $0 and $1,101 respectively)	236,817	202,821
Accrued expenses and other liabilities	28,466	28,486
Deferred income taxes	0	14,899
Deferred revenue	333	16,680
Total current liabilities	293,971	285,311
Unfavorable lease obligation	17,343	19,170
Deferred income taxes	19,186	6,905
Contingent consideration for acquisitions	26,949	30,091
Long-term debt (net of debt issuance costs of $4,105 and $5,152, respectively)	247,251	242,031
Other liabilities	4,910	5,566
Total liabilities	$ 609,610	$ 589,074
COMMITMENTS AND CONTINGENCIES
EQUITY:
Common stock ($.0001 par value; 300,000,000 shares authorized; 43,837,714 and 44,422,881 shares outstanding, respectively)	$ 4	$ 4
Common stock—additional paid-in-capital	474,367	453,109
Retained earnings	169,680	321,083
Accumulated other comprehensive loss	(4,009)	(11)
Treasury stock (3,178,372 and 585,150 shares, respectively)	(28,762)	(4,412)
Total equity attributable to the Company's shareholders	611,280	769,773
Noncontrolling interest	2,730	8,889
Total equity	614,010	778,662
TOTAL LIABILITIES AND EQUITY	$ 1,223,620	$ 1,367,736

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Accounts receivable, amounts owed by related parties	$ 0	$ 36
Accounts payable, amounts owed to related parties	0	1,101
Less: Debt issuance costs (net of accumulated amortization of $ 2,296 and $1,474, respectively)	$ 4,105	$ 5,152
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	300,000,000	300,000,000
Common stock, shares, outstanding (in shares)	43,837,714	44,422,881
Treasury stock, shares outstanding (in shares)	3,178,372	585,150

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
REVENUES:
Biomass-based diesel sales		$ 1,141,281	$ 1,052,772	$ 1,207,618
Biomass-based diesel government incentives		245,868	220,634	290,393
Total biodiesel sales		1,387,149	1,273,406	1,498,011
Services		195	425	127
Total revenue		1,387,344	1,273,831	1,498,138
COSTS OF GOODS SOLD:
Biomass-based diesel		1,272,125	1,070,430	1,209,191
Biomass-based diesel—related parties	[1]	4,542	42,622	49,358
Services		134	167	156
Total cost of goods sold		1,276,801	1,113,219	1,258,705
GROSS PROFIT		110,543	160,612	239,433
SELLING, GENERAL, AND ADMINISTRATIVE EXPENSES (includes related party amounts of $0, $45, and $37, respectively)		73,397	62,681	45,865
RESEARCH AND DEVELOPMENT EXPENSE		16,851	12,424	258
IMPAIRMENT OF GOODWILL		175,028	0	0
INCOME (LOSS) FROM OPERATIONS		(154,733)	85,507	193,310
OTHER INCOME (EXPENSE), NET:
Change in fair value of contingent consideration		359	6,631	0
Other income		5,830	662	388
Interest expense (includes related party amounts of $0, $7, and $30, respectively)		(11,867)	(6,690)	(2,397)
Total other income (expenses)		(5,678)	603	(2,009)
INCOME (LOSS) BEFORE INCOME TAXES		(160,411)	86,110	191,301
INCOME TAX BENEFIT (EXPENSE)		8,701	(3,572)	(4,935)
NET INCOME (LOSS)		(151,710)	82,538	186,366
LESS—NET LOSS ATTRIBUTABLE TO NONCONTROLLING INTEREST		(318)	(73)	0
NET INCOME (LOSS) ATTRIBUTABLE TO THE COMPANY		(151,392)	82,611	186,366
PLUS—GAIN ON REDEMPTION OF PREFERRED STOCK		0	378	0
LESS—EFFECT OF CHANGES TO PREFERRED STOCK		0	(40)	(2,055)
LESS—EFFECT OF PARTICIPATING PREFERRED STOCK		0	(91)	(16,272)
LESS—EFFECT OF PARTICIPATING SHARE-BASED AWARDS		0	(1,238)	(2,785)
NET INCOME (LOSS) ATTRIBUTABLE TO THE COMPANY’S COMMON STOCKHOLDERS		$ (151,392)	$ 81,620	$ 165,254
Net income (loss) per share attributable to common stockholders:
Basic (in dollars per share)		$ (3.44)	$ 2	$ 5
Diluted (in dollars per share)		$ (3.44)	$ 1.99	$ 5
Weighted-average shares used to compute net income (loss) per share attributable to common stockholders:
Basic (in shares)		43,958,803	40,740,411	33,045,164
Diluted (in shares)		43,958,803	40,749,913	33,052,879
[1]	Represents transactions with West Central prior to the Company's determination that West Central was no longer a related party.

Consolidated Statements of Ope5

Consolidated Statements of Operations (Parenthetical) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Selling, general and administrative expenses, related party	[1]	$ 0	$ 45	$ 37
Interest expense, related party	[1]	$ 0	$ 7	$ 30
[1]	Represents transactions with West Central prior to the Company's determination that West Central was no longer a related party.

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (151,710)	$ 82,538	$ 186,366
Unrealized losses on marketable securities, net of taxes of $0, $0 and $0, respectively	0	(11)	0
Foreign currency translation adjustments	(5,022)	0	0
Other comprehensive loss	(5,022)	(11)	0
Comprehensive income (loss)	(156,732)	82,527	186,366
Less—Comprehensive loss attributable to noncontrolling interest	(1,013)	0	0
Comprehensive income (loss) attributable to the Company	$ (155,719)	$ 82,527	$ 186,366

Consolidated Statements of Com7

Consolidated Statements of Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Taxes on unrealized losses on marketable securities	$ 0	$ 0	$ 0

Consolidated Statements of Rede

Consolidated Statements of Redeemable Preferred Stock and Equity Statement - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Common Stock- Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock	Noncontrolling Interest
Beginning Balance at Dec. 31, 2012	$ 324,764	$ 83,043	$ 3	$ 274,136	$ 53,823		$ (3,198)
Beginning Balance (in shares) at Dec. 31, 2012		2,995,106	30,559,935
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock	423			423
Issuance of common stock (in shares)			58,501
Conversion of Series B Preferred Stock to common stock	79,844	$ (79,080)	$ 1	79,843
Conversion of Series B Preferred Stock to common stock (in shares)		2,851,793	5,763,508
Conversion of restricted stock units to common stock (net of shares of treasury stock purchased)	$ (688)						(688)
Treasury stock activity (in shares)	(67,913,000)
Conversion of restricted stock units to common stock (net of shares of treasury stock purchased) (in shares)			124,277
Stock compensation expense	$ 5,416			5,416
Net change in unrealized losses on marketable securities	0
Series B Preferred Stock dividends paid	(2,055)				(2,055)
Net loss	186,366				186,366
Ending Balance at Dec. 31, 2013	594,070	$ 3,963	$ 4	359,818	238,134		(3,886)
Ending Balance (in shares) at Dec. 31, 2013		143,313	36,506,221
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock	582			582
Issuance of common stock (in shares)			49,662
Conversion of Series B Preferred Stock to common stock	23	$ (23)		23
Conversion of Series B Preferred Stock to common stock (in shares)		816	1,634
Preferred stock redemption	378	$ (3,940)			378
Preferred stock redemption (in shares)		(142,497)
Issuance of common stock in acquisitions (net of issuance costs)	80,163			80,163
Issuance of common stock in acquisition (in shares)			7,794,710
Conversion of restricted stock units to common stock (net of shares of treasury stock purchased)	$ (526)						(526)
Treasury stock activity (in shares)	(54,252,000)
Conversion of restricted stock units to common stock (net of shares of treasury stock purchased) (in shares)			70,654
Convertible notes conversion feature (net of taxes of $5,082 and net of issuance cost of $886)	$ 19,068			19,068
Purchase of capped call transactions	(11,904)			(11,904)
Purchase of remaining interest in VIE (net of taxes of $300)	(524)			(524)
Acquisition of noncontrolling interest	8,962							$ 8,962
Stock compensation expense	5,883			5,883
Net change in unrealized losses on marketable securities	(11)					$ (11)
Series B Preferred Stock dividends paid	(40)				(40)
Net loss	82,538				82,611			(73)
Ending Balance at Dec. 31, 2014	778,662		$ 4	453,109	321,083	(11)	(4,412)	8,889
Ending Balance (in shares) at Dec. 31, 2014			44,422,881
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock	412			412
Issuance of common stock (in shares)			37,966
Issuance of common stock in acquisitions (net of issuance costs)	15,310			15,310
Issuance of common stock in acquisition (in shares)			1,675,000
Conversion of restricted stock units to common stock (net of shares of treasury stock purchased)	(854)						(854)
Treasury stock activity	$ (23,473)						(23,473)
Treasury stock activity (in shares)	(92,608,000)		(2,593,222)
Conversion of restricted stock units to common stock (net of shares of treasury stock purchased) (in shares)			295,089
Acquisition of noncontrolling interest	$ (4,828)							(4,828)
Stock compensation expense	5,161			5,161
Net change in unrealized losses on marketable securities	0
Comprehensive income items	(5,011)					(3,998)		(1,013)
Net loss	(151,710)				(151,392)			(318)
Other	341			375	(11)		(23)
Ending Balance at Dec. 31, 2015	$ 614,010		$ 4	$ 474,367	$ 169,680	$ (4,009)	$ (28,762)	$ 2,730
Ending Balance (in shares) at Dec. 31, 2015			43,837,714

Consolidated Statements of Red9

Consolidated Statements of Redeemable Preferred Stock and Equity (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2014USD ($)shares
Statement of Stockholders' Equity [Abstract]
Issuance of common stock, issuance costs	$ 942
Conversion of restricted stock units to common stock, treasury shares purchased (in shares) | shares	54,252,000
Convertible notes conversion feature, taxes	$ 5,082
Convertible notes conversion features, issuance costs	886
Purchase of remaining interest in VIE, taxes	$ 300

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ (151,710)	$ 82,538	$ 186,366
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation expense	24,997	15,255	9,705
Amortization expense of assets and liabilities, net	570	541	(463)
Accretion of asset retirement obligations	72	67	0
Accretion of convertible note discount	4,699	2,635	0
Accretion of marketable securities	189	553	0
Loss on disposal of property, plant and equipment, net	0	291	815
Provision for doubtful accounts	(803)	1,453	309
Stock compensation expense	5,161	5,883	5,416
Impairment of goodwill	175,028	0	0
Impairment of investment	1,915	0	0
Deferred tax expense (benefits)	(8,953)	3,641	9,859
Change in fair value of contingent consideration	(359)	(6,631)	0
Bargain purchase gain	5,358	0	0
Other	(231)	(42)	0
Changes in asset and liabilities, net of effects from mergers and acquisitions:
Accounts receivable	(20,309)	(207,877)	(64,460)
Inventories	29,631	(277)	(40,608)
Prepaid expenses and other assets	16,315	(12,146)	(9,984)
Accounts payable	32,422	143,131	22,386
Accrued expenses and other liabilities	(6,769)	2,336	4,801
Deferred revenue	(16,347)	1,177	15,503
Net cash flows provided from operating activities	80,160	32,528	139,645
CASH FLOWS FROM INVESTING ACTIVITIES:
Cash paid for marketable securities	(52,435)	(80,974)	0
Cash receipts from marketable securities	68,979	63,840	0
Cash paid for purchase of property, plant and equipment	(64,477)	(60,163)	(39,053)
Insurance proceeds for asset impairments	11,027	0	0
Cash receipts from disposal of fixed assets	0	45	330
Transfer into restricted cash	(4,000)	(117,660)	0
Transfer out of restricted cash	15,845	0	0
Cash paid for investments	(1,452)	(2,779)	(4,733)
Cash paid for acquisitions and additional interests, net of cash acquired	(41,409)	(19,369)	(10,933)
Other investing activities	0	27	0
Net cash flows used in investing activities	(67,922)	(217,033)	(54,389)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net borrowings (repayments) on line of credit	6,470	5,693	10,986
Cash received for issuance of debt	104	5,490	3,000
Cash paid for capped call transactions	0	(11,904)	0
Cash received on convertible debt	0	143,750	0
Cash paid on debt	(6,708)	(37,798)	(10,999)
Cash paid for debt issuance costs	(542)	(4,719)	(203)
Cash paid for issuance of common stock and preferred stock	0	(1,587)	(25)
Cash paid for redemption of preferred stock	0	(3,562)	0
Cash paid for treasury stock	(24,350)	(529)	(282)
Cash paid for contingent consideration	(2,248)	0	0
Cash paid for preferred stock dividends	0	(40)	(1,291)
Net cash flows (used in) provided from financing activities	(27,274)	94,794	1,186
NET CHANGE IN CASH AND CASH EQUIVALENTS	(15,036)	(89,711)	86,442
CASH AND CASH EQUIVALENTS, Beginning of period	63,516	153,227	66,785
Effect of exchange rate changes on cash	(1,399)	0	0
CASH AND CASH EQUIVALENTS, End of period	47,081	63,516	153,227
SUPPLEMENTAL DISCLOSURES OF CASH FLOWS INFORMATION:
Cash paid (received) for income taxes	(189)	(1,847)	(7,475)
Cash paid for interest	6,947	4,065	2,336
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES:
Common stock repurchased included in accrued expenses and other liabilities	464	526	529
Amounts included in period-end accounts payable for:
Purchases of property, plant and equipment	7,734	4,220	2,037
Issuance costs	84	311	105
Incentive common stock liability for supply agreement	316	412	583
Issuance of common stock for acquisitions	15,310	80,163
Contingent consideration for acquisitions	5,000	45,950
Debt assumed in acquisition	5,225	129,745
Gain on redemption of preferred stock		$ 378
Issuance of common stock for dividends			764
Issuance of note payable for acquisition			$ 5,135
Amounts included in period end within Accounts receivables related to impairment of property, plant and equipment	$ 1,414

Organization, Presentation, and

Organization, Presentation, and Nature of the Business	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization, Presentation, and Nature of the Business	ORGANIZATION, PRESENTATION, AND NATURE OF THE BUSINESS Renewable Energy Group, Inc. (the "Company" or "REG") is a company focused on providing cleaner, lower carbon intensity products and services while also providing conventional products and services. Today, we principally generate revenue as a leading North American biofuels producer with a nationwide distribution and logistics system. The Company participates in each aspect of biomass-based diesel production, from acquiring feedstock, managing construction and operating biomass-based diesel production facilities, to marketing, selling and distributing biomass-based diesel and its co-products. To do this, REG utilizes this nationwide production, distribution and logistics system as part of an integrated value chain model to focus on converting natural fats, oils and greases into advanced biofuels and converting diverse feedstocks into renewable chemicals. The Company operates a network of ten operating biomass-based diesel production facilities with aggregate nameplate production capacity of 432 million gallons per year, or mmgy, and one fermentation facility. Seven of these plants are “multi-feedstock capable” which allows them to use a broad range of lower cost feedstocks, such as inedible corn oil, used cooking oil and inedible animal fats in addition to vegetable oils, such as soybean oil and canola oil. The Company also has three partially constructed production facilities and one non-operational production facility. The Company will need to raise additional capital to complete construction of these plants and fund working capital requirements. It is uncertain when or if financing will be available. The Company expanded its business to Europe by acquiring a majority interest in Petrotec AG (or Petrotec) in December 2014. Petrotec is a fully-integrated company that produces biodiesel at its two biorefineries in Emden and Oeding, Germany to sell to the European market. The biomass-based diesel industry and the Company’s business have benefited from the continuation of certain federal and state incentives. The federal biodiesel mixture excise tax credit (the "BTC") was reinstated for 2015, will be in effect throughout 2016 and will expire on December 31, 2016. It is uncertain whether the BTC will be reinstated thereafter. The expiration along with other amendments of any one or more of those laws, could adversely affect the financial results of the Company.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Consolidation The consolidated financial statements include the accounts of the Company, its wholly-owned subsidiaries, and entities which it controls. All intercompany balances and transactions have been eliminated for consolidated reporting purposes. Cash and Cash Equivalents Cash and cash equivalents consists of money market funds and demand deposits with financial institutions. The Company considers all highly liquid debt instruments purchased with an original maturity of three months or less to be cash equivalents. Restricted Cash The Company segregates certain cash balances in accordance with lending arrangements and classified restricted cash between current and non-current assets based on the length of time of the restricted use. As of December 31, 2015 and 2014 , current restricted cash amounted to $0 and $12,845 , respectively, which was held in certificates of deposit as pledges for letters of credit issued to support a subsidiary's trade activities and the Company's outstanding tender offer to acquire the remaining interest at Petrotec, see "Note 5 - Acquisitions". Non-current restricted cash consists of a $101,315 certificate of deposit at both December 31, 2015 and 2014 , which was pledged to Bank of America, who issued a letter of credit on the Company's behalf to support the payments on the Company's GOZone Bonds. In addition, non-current restricted cash in the form of certificate of deposit amounts to $4,500 and $3,500 at December 31, 2015 and 2014, respectively, which was pledged to Bank of America, who issued a letter of credit to support a subsidiary's trade activities. For additional information, see "Note 12 - Debt". Marketable Securities The Company’s marketable securities are classified as available-for-sale and are reported at fair value, with unrealized gains and losses, net of tax, recorded in accumulated other comprehensive income (loss). Realized gains or losses and declines in value judged to be other-than-temporary, if any, on available-for-sale securities are reported in other income, net. The Company evaluates the investments periodically for possible other-than-temporary impairment, specifically contemplating whether a sale of the securities is likely to occur before recovery of the entire amortized cost basis. The Company uses the specific identification method when securities are sold or reclassified out of accumulated other comprehensive income into earnings. The Company considers marketable securities maturing in less than one year as short-term. The Company has no outstanding marketable securities as of December 31, 2015 . Realized gains and losses on available-for-sale securities were minimal for the years ended December 31, 2015 and 2014 . Accounts Receivable Accounts receivable are carried at invoiced amount less allowance for doubtful accounts. Management estimates the allowance for doubtful accounts based on existing economic conditions, the financial conditions of customers, and the amount and age of past due accounts. Receivables are considered past due if full payment is not received by the contractual due date. Past due accounts are generally written off against the allowance for doubtful accounts only after reasonable collection attempts have been exhausted. Activity regarding the allowance for doubtful accounts was as follows: Balance, January 1, 2013 $ 1,972 Amount charged to selling, general and administrative expenses 309 Charge-offs, net of recoveries (157 ) Balance, December 31, 2013 2,124 Amount charged to selling, general and administrative expenses 1,453 Charge-offs, net of recoveries (1,304 ) Balance, December 31, 2014 2,273 Amount charged to selling, general and administrative expenses (803 ) Charge-offs, net of recoveries (119 ) Balance, December 31, 2015 $ 1,351 Inventories Inventories are valued at the lower of cost or net realizable value. Cost is determined based on the first-in, first-out method. There were no lower of cost or market adjustments made to the inventory values reported as of December 31, 2015 and 2014 . Renewable Identification Numbers (RINs) When the Company produces and sells a gallon of biomass-based diesel, 1.5 to 1.7 RINs per gallon are generated. RINs are used to track compliance with Renewable Fuel Standards (RFS2). RFS2 allows the Company to attach between zero and 2.5 RINs to any gallon of biomass-based diesel. As a result, a portion of the selling price for a gallon of biomass-based diesel is generally attributable to RFS2 compliance. However, RINs that the Company generates are a form of government incentive and not a result of the physical attributes of the biomass-based diesel production. Therefore, no cost is allocated to the RIN when it is generated, regardless of whether the RIN is transferred with the biomass-based diesel produced or held by the Company pending attachment to other biomass-based diesel production sales. In addition, the Company also obtains RINs from third parties who have separated the RINs from gallons of biomass-based diesel. From time to time, the Company holds varying amounts of these separated RINs for resale. RINs obtained from third parties are initially recorded at their cost and are subsequently revalued at the lower of cost or market as of the last day of each accounting period and the resulting adjustments are reflected in costs of goods sold for the period. The value of RINs obtained from third parties is reflected in “Prepaid expenses and other assets” on the consolidated balance sheet. The cost of goods sold related to the sale of these RINs is determined using the average cost method, while market prices are determined by RIN values, as reported by the Oil Price Information Service (OPIS). The Company records assets acquired and liabilities assumed through the exchange of non-monetary assets based on the fair value of the assets and liabilities acquired or the fair value of the consideration exchanged, whichever is more readily determinable. Derivative Instruments Derivatives are recorded on the balance sheet at fair value with changes in fair value recognized in current period earnings. The Company did not elect to use hedge accounting for all periods presented. Property, Plant and Equipment Property, plant and equipment is recorded at cost less accumulated depreciation. Maintenance and repairs are expensed as incurred. Depreciation expense is computed on a straight-line method based upon estimated useful lives of the assets. Estimated useful lives are as follows: Automobiles and trucks 5 years Computers and office equipment 5 years Office furniture and fixtures 7 years Machinery and equipment 5-30 years Leasehold improvements the lesser of the lease term or 30 years Buildings and improvements 30-40 years In April 2015, the Company experienced a fire at its Geismar facility, resulting in the shutdown of the facility. The Company estimated fixed assets of approximately $11,027 were impaired as a result of the fire. At December 31, 2015, the Company had received property proceeds of $11,027 from insurance for the property damage. In addition, the Company received approximately $4,293 related to the business interruption portion of the claim reimbursing a portion of lost margin during the repairs of the damages caused by the fire. The proceeds for business interruption were recorded as an increase in biomass-based diesel sales in the Company's Consolidated Statements of Operations. In September 2015, another fire occurred at the Geismar facility. The Company estimated fixed assets of approximately $1,414 were impaired by the September fire. The Company believes it is probable that it will recover all the net book value of the assets damaged by the fire under its insurance policies. As such, a receivable was recorded as an offset to the estimated impairment loss. No impact on earnings was recognized. As of December 31, 2015 , 2014 and 2013 , the Company capitalized interest incurred on debt during the construction of assets of $897 , $1,345 and $335 , respectively. Goodwill Goodwill is tested for impairment annually on July 31 or when impairment indicators exist. Goodwill is allocated and tested for impairment by reporting units. The Company has determined that the reporting units subject to the 2015 goodwill impairment analysis were Biomass-based Diesel; Services; and Renewable Chemicals. The analysis is based on a comparison of the carrying value of the reporting unit to its fair value, determined utilizing both a discounted cash flow methodology and a market comparable methodology. The determination of whether or not the asset has become impaired involves a significant level of judgment in the assumptions underlying the approach used to determine the fair value of the Company’s reporting units, which represented a Level 3 asset measured at fair value on a nonrecurring basis subsequent to its original recognition. Changes in estimates of future cash flows caused by items such as unforeseen events or sustained unfavorable changes in market conditions could negatively affect the fair value of the reporting unit’s goodwill asset and result in an impairment charge. The 2015 annual impairment test determined that the fair value of the Biomass-based Diesel reporting unit exceeded its carrying value by approximately 5% , the Services reporting unit exceeded its carrying value by approximately 21% , and the Renewable Chemicals reporting unit exceeded its carrying value by approximately 12% . Subsequent to the Company's 2015 impairment testing, certain triggering events had occurred. The Company’s common stock price declined significantly during the third quarter and into October, reaching a twelve-month low of $7.06 on November 4, 2015. During the three months ended October 31, 2015, the Company’s common stock traded between $7.25 and $11.18 . The $8.57 average closing common stock price during the three months ended October 31, 2015 compared to an average common stock price of $10.84 during the three months ended July 31, 2015. A sustained decline in the Company’s common stock price and the resulting impact on the Company’s market capitalization is one of several qualitative factors the Company considers each quarter when evaluating whether events or changes in circumstances indicate it is more likely than not that a potential goodwill impairment exists. The Company concluded that the decline in common stock price observed during the third and fourth quarter did represent a sustained decline and that triggering events occurred during this period requiring an interim goodwill impairment test as of October 31, 2015. As such, the Company performed another step-one impairment test of its goodwill assets at October 31, 2015. The result of the step-one evaluation was that the fair value of the Services reporting unit again exceeded its carrying value. However, the fair value of the Biomass-based Diesel and Renewable Chemicals reporting units was lower than their carrying values, primarily due to changes in the weighted average cost of capital. In the step-two analysis for October 31, 2015, the implied fair value of goodwill was determined by assigning the fair value of a reporting unit to all the assets and liabilities of that unit (including any unrecognized intangible assets) as if the reporting unit had been acquired in a business combination. If the carrying amount of reporting unit goodwill exceeds the implied fair value of that goodwill, an impairment loss is recognized for that excess. The inputs used to estimate the fair value of the Company’s reporting units are considered Level 3 inputs of the fair value hierarchy and included the following: (1) The Company’s financial projections for its reporting units were based on its analysis of various factors which include, among other things, demands, margins, whether the BTC is reinstated, capital expenditures and economic conditions. Such estimates are consistent with those used in the Company’s budgeting and capital investment reviews, incorporating current market information, historical factors and the regulatory environment; (2) The long-term growth rates assumed for the Company’s reporting units was based on a comparison to similar publicly traded companies, supported by market information obtained from external sources; and (3) The discount rate used to measure the present value of the projected future cash flows was determined by separately estimating borrowing cost of capital, equity cost of capital, and entity structure. Upon completion of step-two of its goodwill impairment test, the Company recorded a non-cash goodwill impairment charge of $175,028 , which is reflected in the Impairment of Goodwill on the Consolidated Statements of Operations. This impairment charge represents a full write-off of goodwill in the Biomass-based Diesel and Renewable Chemicals reporting units. The following table summarizes goodwill for the Company’s reportable segments: Biomass-based Diesel Services Renewable Chemicals Total Beginning balance - January 1, 2014 $ 68,784 $ 16,080 $ — $ 84,864 Acquisitions 68,564 — 34,847 103,411 Ending balance - December 31, 2014 137,348 16,080 34,847 188,275 Finalization of purchase accounting 2,833 — — 2,833 Impairment charge $ (140,181 ) $ — $ (34,847 ) (175,028 ) Ending balance - December 31, 2015 $ — $ 16,080 $ — $ 16,080 Contingent Consideration for Acquisitions Contingent consideration in a business combination is established at the time of the acquisition (See "Note 5 - Acquisitions"). The contingent consideration is adjusted to fair value at each reporting period. The change in fair value is included in change in fair value of contingent consideration on the Consolidated Statements of Operations. Impairment of Long-lived Assets The Company tests its long-lived assets for recoverability when events or circumstances indicate that its carrying amount may not be recoverable. Significant assumptions used in the undiscounted cash flow analysis, when it is required, include the projected demand for biomass-based diesel based on annual renewable fuel volume obligations under the Renewable Fuel Standards (RFS2), the Company's capacity to meet that demand, the market price of biomass-based diesel and the cost of feedstock used in the manufacturing process. For facilities under construction, estimates also include the capital expenditures necessary to complete construction of the plant and the projected costs of financing. There were no asset impairment charges on long-lived assets other than those related to the 2015 Geismar fires of $12,441 , which were fully offset by insurance receipts and/or accounts receivable for insurance coverage, for the years ended December 31, 2015 , 2014 and 2013 . Investments The Company has made investments in several biofuels businesses. These investments are recorded at cost and assessed for impairment at each reporting period. At December 31, 2015 , the Company performed a qualitative and quantitative assessment of the performance of its investments and recorded an impairment charge of $1,915 . This impairment charge was included in Other Income (Expense), on the Consolidated Statements of Operations. There were no impairment charges for the years ended December 31, 2014 and 2013 . Unfavorable Lease Obligation The Company assumed ground and fixture leases as part of certain acquisitions which required the Company to pay above market rentals through the remainder of the lease terms. The unfavorable lease obligation is amortized over the contractual periods the Company is required to make rental payments under the leases. The amount expected to be amortized each year for the remainder of the contracts is $1,828 . Convertible Debt In June 2014, the Company issued $143,750 in convertible senior notes. Applicable authoritative accounting guidance requires that the conversion feature be assigned a fair value and that that feature reduce the initial recorded value of the liability component of the convertible senior notes. This conversion feature is recorded in equity on a net of tax basis. The discount on the liability component is being amortized through interest expense until the maturity date of June 15, 2019. See "Note 12 - Debt" for further descriptions of the transaction. Capped Call Transaction In connection with the issuance of the convertible senior notes, the Company entered into capped call transactions. The purchased capped call transactions were recorded as a reduction to common stock-additional paid-in-capital. Because this was considered to be an equity transaction and qualifies for the derivative scope exception, no future changes in the fair value of the capped call will be recorded by the Company. Share Repurchase Programs In February 2015, the Company's board of directors approved a share repurchase program of up to $30,000 of the Company's shares of Common Stock. The program is in effect through October 31, 2016. Shares may be repurchased from time to time in open market transactions, privately negotiated transactions or by other means. The Company accounts for share repurchases using the cost method. Under this method, the cost of the share repurchase is recorded entirely in treasury stock, a contra equity account. During the year ended December 31, 2015 , the Company repurchased shares of Common Stock in the amount of $23,313 under this share repurchase program. Foreign Currency Transactions and Translation The Company’s reporting and functional currency is U.S. dollars. Monetary assets and liabilities denominated in currencies other than U.S. dollars are remeasured into their respective functional currencies at exchange rates in effect at the balance sheet date. The resulting exchange gain or loss is included in the Company’s Consolidated Statements of Operations as foreign exchange gain (loss) unless the remeasurement gain or loss relates to an intercompany transaction that is of a long-term investment nature and for which settlement is not planned or anticipated in the foreseeable future. Gains or losses arising from translation of such transactions are reported as a component of accumulated other comprehensive income (loss) in the Company’s Consolidated Balance Sheets. The Company translates the assets and liabilities of its foreign subsidiaries from their respective functional currencies to U.S. dollars at the appropriate spot rates as of the balance sheet date. Generally, our foreign subsidiaries use the local currency as their functional currency. Changes in the carrying value of these assets and liabilities attributable to fluctuations in spot rates are recognized in foreign currency translation adjustment, a component of accumulated other comprehensive income (loss) in the Company’s Consolidated Balance Sheets. The other comprehensive loss amounts presented in the Company's Consolidated Statements of Comprehensive Income (Loss) and Consolidated Statements of Redeemable Preferred Stock and Equity mainly include the foreign currency translation adjustment resulting from translating the financial statements of Petrotec AG from Euros to US Dollars, the Company's functional currency. Revenue Recognition The Company recognizes revenues from the following sources: • the sale of biomass-based diesel and its co-products, as well as Renewable Identification Numbers (RINs) and raw material feedstocks, purchased or produced by the Company at owned manufacturing facilities and manufacturing facilities with which the Company has tolling arrangements; • the resale of biomass-based diesel, RINs and raw material feedstocks acquired from third parties; • the sale of petroleum-based heating oil and diesel fuel acquired from third parties, along with the sale of these items further blended with biodiesel produced at wholly owned facilities; • incentives received from federal and state programs for renewable fuels; and • fees received for the marketing and sales of biomass-based diesel produced by third parties and from managing operations of third party facilities. Biomass-based diesel, including RINs, and raw material feedstock revenues are recognized where there is persuasive evidence of an arrangement, delivery has occurred, the price has been fixed or is determinable and collectability can be reasonably assured. Fees received under toll manufacturing agreements with third parties are generally established as an agreed upon amount per gallon of biomass-based diesel produced. The fees are recognized where there is persuasive evidence of an arrangement, delivery has occurred, the price has been fixed or is determinable and collectability can be reasonably assured. Revenues associated with the governmental incentive programs are recognized when the amount to be received is determinable, collectability is reasonably assured and the sale of product giving rise to the incentive has been recognized. The Company received funds from the United States Department of Agriculture (USDA) in the amount of $624 , $600 and $2,813 for the years ended December 31, 2015 , 2014 and 2013 , respectively. The Company records amounts when it has received notification of a payment from the USDA or is in receipt of the funds and records the awards under the Program in "Biodiesel government incentives" as they are closely associated with the Company's biomass-based diesel production activities. On December 18, 2015, President Obama signed into law the Protecting Americans from Tax Hikes Act of 2015, which reinstated and extended a set of tax provisions, including the retroactive reinstatement for 2015 and extension for 2016 of the BTC. All amounts to be received from the government are included within Biomass-based diesel government incentives on the Consolidated Statements of Operations. In addition, given the uncertainty around the reinstatement of the BTC, the Company and other market participants entered into agreements with both customers and vendors throughout the year to handle how any potential future BTC would be captured. The impacts of the agreements with customers are recorded net as adjustments to Biomass-based diesel sales, whereas agreements with vendors are recorded net as adjustments to Biomass-based diesel costs of goods sold on the Consolidated Statements of Operations. As a result of the reinstatement of the BTC, in combination with these agreements, the Company recognized a net benefit of $95,008 and $78,781 for the years ended December 31, 2015 and 2014, respectively. As the BTC was enacted for all of 2013, there were no such agreements. Freight Amounts billed to customers for freight are included in biomass-based diesel sales. Costs incurred for freight are included in costs of goods sold. Advertising Costs Advertising costs are charged to expense as they are incurred. Advertising and promotional expenses were $1,288 , $755 and $648 for the years ended December 31, 2015 , 2014 and 2013 , respectively. Research and Development Research and development (R&D) costs are charged to expense as incurred. In process research and development (IPR&D) assets acquired in connection with acquisitions are recorded on the Consolidated Balance Sheets as intangible assets. Acquired IPR&D is initially assigned an indefinite life and is subject to impairment testing until the completion or abandonment of the associated R&D efforts. If abandoned, the carrying value of the IPR&D asset is expensed. Once the associated R&D efforts are completed, the carrying value of the IPR&D is reclassified as a finite-lived asset and is amortized over its useful life. The Company assessed its indefinite life intangible assets for impairment at December 31, 2015 and 2014. No impairment was identified related to the Company's IPR&D balance at December 31, 2015 and 2014. Employee Benefits Plan The Company sponsors an employee savings plan under Section 401(k) of the Internal Revenue Code. The Company makes matching contributions equal to 50% of the participant’s pre-tax contribution up to a maximum of 6% of the participant’s eligible earnings. Total expense related to the Company’s defined contribution plan was $1,071 , $855 and $533 for the years ended December 31, 2015 , 2014 and 2013 , respectively. Stock-Based Compensation Stock-based compensation expense is measured at the grant-date fair value of the award and recognized as compensation expense over the vesting period. Income Taxes The Company uses the asset and liability method to account for income taxes. Accordingly, deferred income taxes are recognized for differences between the financial statement and tax bases of assets and liabilities at enacted statutory tax rates in effect for the years in which differences are expected to reverse. Changes in tax rates are recognized directly to the income statement as they arise. Consideration is given to positive and negative evidence related to the realization of the deferred tax assets and valuation allowances are established to reduce deferred tax assets to the amounts expected to be realized. Significant judgment is required in making this assessment. For uncertain tax positions, the Company recognizes tax benefits that are more likely than not to be sustained upon examination by tax authorities. The amount recognized is measured as the largest amount of benefit that is greater than 50 percent likely to be realized. With regard to non-US subsidiaries, the Company will indefinitely reinvest any future earnings outside of the U.S. and currently does not have any undistributed earnings. Concentrations One customer represented slightly less than 10% of the total consolidated revenues of the Company for the year ended December 31, 2015. This customer accounted for more than 10% of the total consolidated revenues of the Company for the two years ended December 31, 2014 and 2013 . All customer amounts disclosed in the table are related to biomass-based diesel sales: 2015 2014 2013 Customer A $ 114,030 $ 231,780 $ 243,258 The Company maintains cash balances at financial institutions, which may at times exceed the $250 coverage by the U.S. Federal Deposit Insurance Company. 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, disclosure of contingent assets and liabilities at the dates of the financial statements and reported amounts of revenues and expenses during the reporting periods. These estimates are based on information that is currently available to management and on various assumptions that the Company believes to be reasonable under the circumstances. Actual results could differ from those estimates. New Accounting Pronouncements In April 2015, the FASB issued ASU 2015-03 S implifying the Presentation of Debt Issuance Costs . The amendments in this update require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The guidance in the ASU is effective for financial statements issued for fiscal years beginning after December 15, 2015 and interim periods within fiscal years beginning after December 15, 2016. The Company has evaluated the impact of this guidance on its consolidated financial statements and elected to early adopt the guidance in the year ended December 31, 2015. Early adoption of the guidance did not have any material impact on the Company's consolidated financial statements for the year ended December 31, 2015. Certain amounts on the consolidated financial statements have been reclassified to conform to the current year's presentation as a result of early adopting the guidance. In July 2015, the FASB issued ASU 2015-11, S implifying the Measurement of Inventory , which requires entities to measure most inventory “at the lower of cost and net realizable value,” thereby simplifying the current guidance under which an entity must measure inventory at the lower of cost or market. The guidance is effective prospectively for annual periods beginning after December 15, 2016, and interim periods therein. The Company has evaluated the impact of this guidance on its consolidated financial statements and elected to early adopt the guidance in the year ended December 31, 2015 given the level and nature of its inventory turnover. Early adoption of the guidance did not have any material impact on the Company's consolidated financial statements for the year ended December 31, 2015. In July 2015, the FASB decided to defer by one year the effective dates of the new revenue recognition standard as provided by the ASU 2014-09, Revenue from Contracts with Customers: Summary and Amendments that Create Revenue from Contracts with Customers and Other Assets and Deferred Costs—Contracts with Customers . Early adoption is permitted for all entities, but not before the original public entity effective date. For public companies, the update will now be effective for interim and annual periods beginning after December 15, 2017. The Company is currently evaluating the impact that this guidance will have on its consolidated financial statements. In September 2015, the FASB issued ASU 2015-16, Business Combinations (Topic 805): Simplifying the Accounting Measurement-Period Adjustments that eliminates the requirement that an acquirer in a business combination account for measurement-period adjustments retrospectively. Instead, a measurement-period adjustment will be recognized in the period in which it determines the amount of the adjustment. The guidance is effective for public business entities for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. The Company is currently evaluating the impact this guidance will have on its consolidated financial statements. In November 2015, the FASB issued ASU 2015-17, Income Taxes, Balance Sheet Classification of Deferred Taxes , requiring entities to classify all deferred tax assets and liabilities as noncurrent on the balance sheet instead of separating deferred taxes into current and noncurrent accounts. All valuation allowances are required to be classified as noncurrent. The guidance is effective for financial statements issued for annual periods beginning after December 15, 2016, and interim periods within those annual periods. The Company has evaluated the impact of this guidance on its consolidated financial statements and elected to early adopt the guidance for the year ended December 31, 2015. In January 2016, the FASB issued ASU 2016-01, Financial instruments - Overall - Recognition and Measurement of Financial Assets and Financial Liabilities , which requires entities to measure equity investments that do not result in consolidation and are not accounted for under the equity method at fair value and recognize any changes in fair value in net income unless the investment qualify for the new practicability exception. The guidance is effective for calendar-year public entities beginning in 2018. The Company is still evaluating the impact of this guidance, but does not expect it to have any material impact on its consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, Leases , that requires lessees to put most leases on their balance sheets but recognize expenses on their income statements in a manner similar to today’s accounting. The guidance also eliminates today’s real estate-specific provisions for all entities. For lessors, the guidance modifies the classification criteria and the accounting for sales-type and direct financing leases. The guidance is effective for calendar-year public entities beginning in 2019. The Company is still evaluating the impact of this guidance on its consolidated financial statements.

Stockholders' Equity of the Com

Stockholders' Equity of the Company	12 Months Ended
	Dec. 31, 2015
Stockholders' Equity Attributable to Parent [Abstract]
Stockholders' Equity of the Company	STOCKHOLDERS’ EQUITY OF THE COMPANY Common Stock The Company has authorized capital stock consisting of 450,000,000 shares, all with a par value of $.0001 per share, which includes 300,000,000 shares of Common Stock, 140,000,000 shares of Common Stock A and 10,000,000 shares of Preferred Stock including 3,000,000 shares of Series B Preferred Stock. Each holder of Common Stock is entitled to one vote for each share of Common Stock held on all matters submitted to a vote of stockholders. Subject to preferences that may apply to shares of previously outstanding Series A Preferred Stock and currently outstanding Series B Preferred Stock as outlined below, the holders of outstanding shares of Common Stock are entitled to receive dividends. After the payment of all preferential amounts required to the holders of Series B Preferred Stock, all of the remaining assets of the Company available for distribution shall be distributed ratably among the holders of Common Stock. Common Stock Warrants Under the Company’s outstanding warrants, the holder may purchase the number of shares of Common Stock underlying each warrant held for a purchase price of $11.16 per share. The warrant holder may “net exercise” the warrants and use the common shares received upon exercise of the warrants outstanding as the consideration for payment of the exercise price. The warrant holders are generally protected from anti-dilution by adjustments for any stock dividends, stock split, combination, or other recapitalization. No common stock warrants were issued during 2015 or 2014 . All the warrants expired on February 25, 2015. No common stock warrants were outstanding at December 31, 2015 . Stock Issuance Costs Other direct costs of obtaining capital by issuing the common and preferred stock were deducted from related proceeds with the net amount recorded as preferred stock or stockholders’ equity. Direct costs incurred for the years ended December 31, 2015 , 2014 and 2013 were $0 , $1,587 and $114 , respectively.

Redeemable Preferred Stock

Redeemable Preferred Stock	12 Months Ended
	Dec. 31, 2015
Temporary Equity Disclosure [Abstract]
Redeemable Preferred Stock	REDEEMABLE PREFERRED STOCK During the third quarter 2013, the Company's closing sale price of its Common Stock exceeded $15.00 for at least 20 days in a 30 consecutive trading day period with the average daily trading volume exceeding 200,000 shares. Therefore, the Company opted to cause 50% of the then-outstanding shares of Series B Preferred Stock to be converted as provided for in the preferred stock shareholder agreement. The Company converted 518,365 shares of Series B Preferred Stock into 1,047,465 shares of Common Stock. In March 2014, the Company redeemed all outstanding shares of Series B Preferred Stock. No shares of Series B Preferred Stock remain outstanding at December 31, 2015 and 2014 .

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2015
Business Combinations [Abstract]
Acquisitions	ACQUISITIONS 2015 acquisitions Imperium Renewables, Inc. On August 19, 2015, the Company acquired substantially all the assets of Imperium Renewables, Inc. (Imperium), including the 100 -mmgy nameplate biomass-based diesel refinery and deepwater port terminal at the Port of Grays Harbor, Washington. The results of Imperium's operations have been included in the consolidated financial statements since that date. The Company has finalized its accounting of this business combination during the fourth quarter of 2015. The following table summarizes the consideration paid for Imperium: August 19, 2015 Consideration at fair value for Imperium: Cash $ 36,748 Common stock 15,310 Contingent consideration 5,000 Total $ 57,058 The fair value of the 1,675,000 shares of Common Stock issued to Imperium was determined using the closing market price of the Company's common shares at the date of acquisition. Subject to achievement of certain milestones related to the biomass-based diesel gallons produced and sold by REG Grays Harbor and whether the BTC is reinstated, Imperium may receive certain contingent consideration (Earnout Payments) over a two -year period after the acquisition. The Earnout Payments will be payable in cash. As of December 31, 2015 , the Company has recorded a contingent liability of $4,913 , approximately $3,534 of which has been classified as current on the Consolidated Balance Sheets. The following table summarizes the estimated fair values of the assets acquired and liabilities assumed at the acquisition date. August 19, 2015 Assets (liabilities) acquired of Imperium: Cash $ 168 Accounts receivable 8,274 Inventory 18,989 Other current assets 87 Property, plant and equipment 46,476 Intangible assets 2,900 Total identifiable assets acquired 76,894 Accounts payable (4,828 ) Accrued expenses and other liabilities (942 ) Debt (5,225 ) Deferred tax liabilities (3,483 ) Total liabilities assumed (14,478 ) Net identifiable assets acquired 62,416 Less: Bargain purchase gain 5,358 Net assets acquired $ 57,058 Imperium was acquired at a price less than fair value of the net identifiable assets, and the Company recorded a net of tax bargain purchase gain of $5,358 . All future adjustments will be reported in the Consolidated Statements of Operations. The bargain purchase gain is reported in the "Other Income, Net" on the Consolidated Statements of Operations. Prior to recognizing a bargain purchase gain, the Company reassessed whether all assets acquired and liabilities assumed had been correctly identified as well as the key valuation assumptions and business combination accounting procedures for this acquisition. After careful consideration and review, the Company concluded that the recognition of a bargain purchase gain was appropriate for this acquisition. Factors that contributed to the bargain purchase price were: • The assets were not fully utilized by the seller and that the transaction was completed with a motivated seller that appeared to have recapitalized its investments and desired to exit the facilities that no longer fit its strategy given the uncertainties in the industry. • The Company was able to complete the acquisition in an expedient manner, with a cash payment, stock issuance and without a financial contingency, which was a key attribute for the seller. The relatively small size of the transaction for the Company, the lack of required third-party financing and the Company's expertise in completing similar transactions in the past gave the seller confidence that the Company could complete the transaction quickly and without difficultly. • Due to the unique nature of the products and limited number of potential buyers for this business, the seller found it advantageous to accept the Company's purchase price based upon our demonstrated ability to operate similar businesses, and financial strength that may enable the Company to make improvement and run the business at increased production rates in the long run. The following pro forma condensed combined results of operations assume that the Imperium acquisition was completed as of January 1, 2013 and as if the stock had been issued on the same date. Year ended December 31, 2015 Year ended December 31, 2014 Year ended December 31, 2013 Revenues $ 1,505,513 $ 1,453,331 $ 1,556,798 Net income (loss) attributable to the Company's common stockholders (155,870 ) 94,129 172,314 Basic net income (loss) per share attributable to common stockholders $(3.46) $2.22 $4.96 2014 acquisitions Petrotec AG On December 24, 2014, the Company acquired 69.08% of the outstanding common shares and voting interest of Petrotec. The results of Petrotec’s operations have been included in the consolidated financial statements since that date. During the last quarter of 2015, the Company completed its purchase accounting for this business combination. The finalization of the purchase price allocation did not result in material adjustments. The following table summarizes the consideration paid for Petrotec: December 24, 2014 Consideration at fair value for Petrotec: Common stock $ 20,022 The fair value of the 2,070,538 common shares issued to Petrotec was determined on the basis of the closing market price of the Company's common shares at the date of acquisition. The following table summarizes the fair values of the assets acquired and liabilities assumed at the acquisition date as the purchase price allocation was finalized: December 24, 2014 Assets (liabilities) acquired of Petrotec: Cash $ 13,523 Accounts receivable 4,989 Inventory 9,470 Other current assets 3,583 Property, plant and equipment 25,026 Other noncurrent assets 369 Total identifiable assets acquired 56,960 Accounts payable (8,171 ) Accrued expenses and other liabilities (2,151 ) Debt (16,192 ) Non-current liabilities (1,462 ) Total liabilities assumed (27,976 ) Net identifiable assets acquired 28,984 Non-controlling interest (8,962 ) Net assets acquired $ 20,022 The fair value of the 30.92% noncontrolling interest in Petrotec is estimated to be $8,962 at the date of the acquisition. The fair value of the noncontrolling interest was estimated using a combination of the income approach and a market approach. The Company recognized $1,289 of acquisition related costs that were expensed in the period the acquisition occurred. During 2015, the Company acquired additional common shares of Petrotec as part of the cash tender offers and open market purchases for $4,828 . At December 31, 2015, the Company owned 87.49% of the outstanding common shares and voting interest of Petrotec. In April 2015, Petrotec's application to de-list its shares of common stock from the Frankfurt Stock Exchange was approved. From the end of the October 8, 2015 trading day, Petrotec's shares of common stock are no longer traded on a regulated market of any stock exchange. Syntroleum Corporation/Dynamic Fuels, LLC On June 3, 2014, REG Synthetic Fuels, a wholly-owned subsidiary of the Company included in the Biomass-based diesel segment, acquired substantially all the assets of Syntroleum, which consisted of a 50% limited liability company membership interest in Dynamic Fuels, as well as intellectual property and other assets. Dynamic Fuels owns a 75 mmgy nameplate capacity renewable hydrocarbon diesel biorefinery located in Geismar, Louisiana. The following table summarizes the consideration paid for Syntroleum. June 3, 2014 Consideration at fair value for Syntroleum: Common stock $ 34,831 The fair value of the 3,493,613 shares of Common Stock issued to Syntroleum was determined on the basis of the closing market price of the Company's common shares at the date of acquisition. The fair value of the Syntroleum renewable hydrocarbon diesel technology was determined using the relief from royalty method, or RFR, which reflects the savings realized by owning the intangible assets. The value under RFR method is dependent upon the following factors for an asset: royalty rate, discount rate, expected life and projected revenue. On June 6, 2014, REG Synthetic Fuels acquired the remaining 50% ownership interest in Dynamic Fuels, from Tyson Foods. The Company renamed Dynamic Fuels to REG Geismar, LLC, which is included in the Biomass-based diesel segment. The finalization of the purchase price allocation resulted in an increase in goodwill of $3,202 relating to higher than initially estimated net operating losses prior to the acquisition of Syntroleum and Dynamic Fuels. The following table summarizes the consideration paid to Tyson Foods for Dynamic Fuels: June 6, 2014 Consideration at fair value for Dynamic Fuels: Cash $ 16,447 Contingent consideration 28,900 Total $ 45,347 The following table summarizes the amount of assets acquired and liabilities assumed at the acquisition date for the combined acquisition of Syntroleum and Dynamic Fuels: June 6, 2014 Assets (liabilities) acquired of Syntroleum and Dynamic Fuels: Cash $ 253 Other current assets 4,666 Property, plant and equipment 121,567 Goodwill 71,398 Intangible assets 8,900 Other noncurrent assets 10,281 Other current liabilities (1,024 ) Deferred tax liabilities (8,310 ) Debt (113,553 ) Other noncurrent liabilities (14,000 ) Total $ 80,178 Subsequent to the closing of the Tyson Foods transaction, REG Geismar paid off the debt owed to Tyson Foods in the amount of $13,553 . Subject to achievements related to the sale of renewable hydrocarbon diesel at the REG Geismar production facility, Tyson Foods may receive contingent consideration of up to $35,000 . The Company will pay contingent consideration, if and when, the Company achieves certain sales volumes. The agreement calls for periodic payments based on pre-determined payments per gallon of product sold. The probability weighted contingent payments were discounted using a risk adjusted discount rate of 5.8% . The contingent payments will be payable in cash. As of December 31, 2015 , the Company has recorded a contingent liability of $29,209 , of which $7,270 has been classified in accrued expenses and other liabilities on the Consolidated Balance Sheets. LS9, Inc. On January 22, 2014, REG Life Sciences, a wholly-owned subsidiary of the Company, acquired substantially all of the assets and certain liabilities of LS9. This acquisition's finalized purchase price allocation did not result in material adjustments. The following table summarizes the consideration paid and the amounts of assets acquired and liabilities assumed at the acquisition date: January 22, 2014 Consideration at fair value: Cash $ 15,275 Common stock 26,254 Contingent consideration 17,050 Total $ 58,579 January 22, 2014 Assets (liabilities) acquired: Property, plant and equipment $ 8,215 In-process research & development intangible assets 15,956 Goodwill 34,846 Other noncurrent liabilities (438 ) Total $ 58,579 The fair value of the 2,230,559 shares of Common Stock issued as part of the consideration paid for LS9 was determined on the basis of the closing market price of the Company's common shares at the date of acquisition. Subject to achievement of certain milestones related to the development and commercialization of products from LS9’s technology, LS9 may receive contingent consideration of up to $21,500 (Earnout Payments) over a five -year period after the acquisition. The Earnout Payments will be payable in cash, the Company's stock or a combination of cash and stock at the Company's election. As of December 31, 2015 and 2014 , the Company has recorded a contingent liability of $7,590 and $8,624 , respectively, $3,958 and $0 , respective of which has been classified as current on the Consolidated Balance Sheets. 416 S. Bell, LLC Prior to July 25, 2014, the Company had a 50% ownership in 416 S Bell, LLC (Bell, LLC), a variable interest entity (VIE) joint venture that owned and leased to the Company its corporate office building in Ames, Iowa. Commencing January 1, 2011, the Company had the right to execute a call option with the joint venture member, Dayton Park, LLC (Dayton Park), to purchase Bell, LLC and commencing on January 1, 2013, Dayton Park had the right to execute a put option with the Company to sell Bell, LLC. The Company determined it was the primary beneficiary of Bell, LLC and had consolidated Bell, LLC into the Company’s financial statements since January 1, 2011. On July 25, 2014, the Company completed the acquisition of the remaining 50% interest in Bell, LLC in exchange for $1,423 cash. The Company determined that this transaction did not result in a change of control and as such has accounted for it as an equity transaction. Neither goodwill nor a gain/loss was recognized in conjunction with the acquisition. 2013 acquisitions Soy Energy, LLC On July 30, 2013, the Company and REG Mason City, LLC (REG Mason City), a subsidiary of the Company, completed the acquisition of substantially all the assets of Soy Energy, LLC's (Soy Energy) assets in exchange for $10,933 cash and the issuance of a $5,135 promissory note to Soy Energy. The assets of Soy Energy consisted of a 30 mmgy nameplate capacity biomass-based diesel facility and related assets, located in Mason City, Iowa. The Company determined that the Soy Energy assets were not a business as defined under ASC Topic 805, on the basis that the assets were not an integrated set of activities or assets that were capable of being conducted or managed in a manner that would provide any economic benefit to the Company. As a result, the Company accounted for the Soy Energy assets as an asset acquisition. Neither goodwill nor a gain from a bargain purchase was recognized in conjunction with the acquisition. The final purchase price allocation resulted in $16,085 of property, plant and equipment and $17 of other current liabilities.

Marketable Securities

Marketable Securities	12 Months Ended
	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	MARKETABLE SECURITIES The Company's investments in marketable securities are stated at fair value and are available-for-sale. The Company has no outstanding marketable securities as of December 31, 2015 . The following table summarizes the Company's marketable securities at December 31, 2014: As of December 31, 2014 Maturity Gross Amortized Cost Total Unrealized Gains Total Unrealized Losses Fair Value Corporate bonds Within one year $ 6,781 $ — $ (6 ) $ 6,775 Certificates of deposit Within one year 10,000 — (5 ) 9,995 Total $ 16,781 $ — $ (11 ) $ 16,770

Inventories

Inventories	12 Months Ended
	Dec. 31, 2015
Inventory Disclosure [Abstract]
Inventories	INVENTORIES Inventories consist of the following at December 31: 2015 2014 Raw materials $ 28,989 $ 23,117 Work in process 3,014 2,879 Finished goods 53,887 71,512 Total $ 85,890 $ 97,508

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	PROPERTY, PLANT AND EQUIPMENT Company's owned property, plant and equipment consists of the following at December 31: 2015 2014 Land $ 4,221 $ 3,437 Building and improvements 103,199 96,298 Leasehold improvements 8,149 10,023 Machinery and equipment 397,632 355,332 513,201 465,090 Accumulated depreciation (75,119 ) (53,889 ) 438,082 411,201 Construction in process 136,502 81,995 Total $ 574,584 $ 493,196 The increase in the December 31, 2015 Construction in process balance is mainly related to the projects at REG Geismar, LLC and REG Danville, LLC in the amount of $37,258 and $15,986 , respectively.

Intangible Assets

Intangible Assets	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	INTANGIBLE ASSETS Amortizing intangible assets consist of the following at December 31: December 31, 2015 Cost Accumulated Amortization Net Weighted Average Remaining Life Raw material supply agreement $ 6,230 $ (1,551 ) $ 4,679 10.0 years Renewable hydrocarbon diesel technology 8,300 (876 ) 7,424 13.5 years Acquired customer relationships 2,900 (106 ) 2,794 9.6 years Ground lease 200 (112 ) 88 5.9 years Total amortizing intangibles 17,630 (2,645 ) 14,985 In-process research and development, indefinite lives 15,956 — 15,956 Total intangible assets $ 33,586 $ (2,645 ) $ 30,941 December 31, 2014 Cost Accumulated Amortization Net Weighted Average Remaining Life Raw material supply agreement $ 5,914 $ (1,113 ) $ 4,801 11.0 years Renewable hydrocarbon diesel technology 8,300 (323 ) 7,977 14.5 years Ground lease 200 (97 ) 103 6.9 years Total amortizing intangibles 14,414 (1,533 ) 12,881 In-process research and development, indefinite lives 15,956 — 15,956 Total intangible assets $ 30,370 $ (1,533 ) $ 28,837 The raw material supply agreement acquired is amortized over its 15 year term based on actual usage under the agreement and expires in 2025. The Company determined the estimated amount of raw materials to be purchased over the life of the agreement to calculate a per pound rate of consumption. The rate is then multiplied by the actual usage each period for expense reporting purposes. Amortization expense of $1,112 , $1,298 and $325 for intangible assets was recorded for the years ended December 31, 2015 , 2014 and 2013 , respectively. Estimated amortization expense for fiscal years ended December 31 is as follows: 2016 $ 1,329 2017 1,343 2018 1,357 2019 1,372 2020 1,388 Thereafter 8,196 Total $ 14,985

Other Assets

Other Assets	12 Months Ended
	Dec. 31, 2015
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other Assets	OTHER ASSETS Prepaid expenses and other current assets consist of the following at December 31: 2015 2014 Commodity derivatives and related collateral, net $ 10,097 $ 12,938 Prepaid expenses 8,504 7,901 Deposits 3,824 4,481 RIN inventory 5,656 10,795 Taxes receivable 1,814 2,843 Other 1,987 4,177 Total $ 31,882 $ 43,135 RIN inventory is valued at the lower of cost or net realizable value and consists of (i) RINs the Company generates in connection with its production of biomass-based diesel and (ii) RINs acquired from third parties. RINs generated by the Company are recorded at no cost, as these RINs are government incentives and not a tangible output from its biomass-based diesel production. The cost of RINs acquired from third parties is determined using the average cost method. RIN market value is based upon pricing as reported by the Oil Price Information Service (OPIS). Since RINs generated by the Company have zero cost associated to them, the lower of cost or market adjustment in RIN inventory reflects only the value of RINs obtained from third parties. RIN inventory values were adjusted in the amount of $3,027 and $1,042 at December 31, 2015 and 2014 , respectively, to reflect the lower of cost or market. Other noncurrent assets consist of the following at December 31: 2015 2014 Spare parts inventory $ 2,922 $ 3,440 Deposits 2,370 4,370 Other 6,527 6,624 Total $ 11,819 $ 14,434

Accrued Expenses and Other Liab

Accrued Expenses and Other Liabilities	12 Months Ended
	Dec. 31, 2015
Accrued Liabilities [Abstract]
Accrued Expenses and Other Liabilities	ACCRUED EXPENSES AND OTHER LIABILITIES Accrued expenses and other liabilities consist of the following at December 31: 2015 2014 Accrued property taxes $ 1,056 $ 1,412 Accrued employee compensation 8,776 10,639 Accrued interest 578 683 Deferred grant revenue — 745 Contingent consideration, current portion 14,762 9,228 Unfavorable lease obligation, current portion 1,828 1,828 Other 1,466 3,951 Total $ 28,466 $ 28,486 Other noncurrent liabilities consist of the following at December 31: 2015 2014 Straight-line lease liability $ 2,751 $ 3,111 Asset retirement obligations 1,062 990 Other 1,097 1,465 Total $ 4,910 $ 5,566

Debt

Debt	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Debt	DEBT The Company’s term debt at December 31 is as follows: 2015 2014 2.75% Convertible debt, $143,750 face amount, due in June 2019 $ 126,053 $ 121,354 REG Geismar GOZone bonds, secured, variable interest rate, due in October 2033 100,000 100,000 REG Danville term loan, secured, variable interest rate of LIBOR plus 5%, due in November 2015 — 1,513 REG Newton term loan, secured, variable interest rate of LIBOR plus 4%, due in December 2018 16,800 19,868 REG Mason City term loan, fixed interest rate of 5%, due in July 2019 3,675 4,566 REG Ames term loans, secured, fixed interest rates of 3.5% and 4.25%, due in January 2018 and December 2019, respectively 3,901 4,226 REG Grays Harbor term loan, variable interest of minimum 3.5% or Prime Rate plus 0.25%, due in May 2022 5,225 — Other 908 1,402 Total debt before debt issuance costs 256,562 252,929 Less: Current portion of long-term debt 5,206 5,746 Less: Debt issuance costs (net of accumulated amortization of $ 2,296 and $1,474, respectively) 4,105 5,152 Total long-term debt $ 247,251 $ 242,031 Convertible Debt In June 2014, the Company issued $143,750 in convertible senior notes (Convertible Notes) with a maturity date of June 15, 2019, unless earlier converted or repurchased. The initial conversion rate is 75.3963 shares of Common Stock per $1 principal amount of Convertible Notes, which represents an initial conversion price of approximately $13.26 per share. The conversion rate will be subject to adjustment in some events but will not be adjusted for any accrued and unpaid interest. Certain corporate events that occur prior to the stated maturity date can cause the Company to increase the conversion rate for a holder. Prior to December 15, 2018, holders may convert all or any portion of their Convertible Notes only under certain limited circumstances where the sale price of Common Stock for a period of time is (i) greater than or equal to 130% of the conversion price of the Convertible Notes on each applicable trading day; (ii) less than 98% of the product of the last reported sale price of the Common Stock and the conversion rate of the Convertible Notes on each applicable trading day; or (iii) upon the occurrence of specified corporate events. On or after December 15, 2018 until the close of business on the second scheduled trading day immediately preceding the maturity date of the Convertible Notes, holders may convert their Convertible Notes at any time, regardless of the foregoing circumstances. Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of Common Stock or a combination of cash and shares of Common Stock, at the Company’s election. The Company's current intent is to settle the principal amount of the Senior Notes in cash upon conversion. If the conversion value exceeds the principal amount, the Company would deliver shares of its common stock in respect to the remainder of its conversion obligation in excess of the aggregate principal amount (conversion spread). The Convertible Notes are not redeemable at the Company’s option prior to maturity. In accounting for the issuance of the Convertible Notes, the Company separated the Convertible Notes into liability and equity components. The carrying amount of the liability component was calculated by measuring the estimated fair value of a similar liability that does not have an associated convertible feature. The carrying amount of the equity component representing the conversion option was determined by deducting the fair value of the liability component from the face value of the Convertible Notes as a whole. The excess of the face amount of the liability component over its carrying amount is amortized to interest expense over the term of the Convertible Notes using the effective interest method with an effective interest rate of 3.80% per annum. The gross proceeds of $143,750 were accordingly allocated between long-term debt for $118,719 and stockholders' equity $25,031 . Issuance costs of $4,563 were paid, which were allocated between deferred financing costs and equity. In connection with the issuance of the Convertible Notes, the Company entered into capped call transactions (Capped Call) in private transactions. Under the Capped Call, the Company purchased capped call options that in aggregate relate to 92.5% of the total number of shares of the Company's Common Stock underlying the Convertible Notes, with a strike price equal to the conversion price of the Convertible Notes and with a cap price equal to $16.02 per share. The capped calls were purchased for $11,904 and recorded as a reduction to common stock-additional paid-in-capital. The purchased Capped Call allows the Company to receive shares of its Common Stock and/or cash from counterparties equal to the amounts of Common Stock and/or cash related to the excess of the market price per share of the Common Stock, as measured under the terms of the Capped Call over the strike price of the Capped Call during the relevant valuation period. The purchased Capped Call is intended to reduce the potential dilution to Common Stock upon future conversion of the Convertible Notes by effectively increasing the initial conversion price to $16.02 as well as to offset potential cash payments the Company is required to make in excess of the principal amount of the Convertible Notes in applicable events. The Capped Call is a separate transaction entered into by the Company with the Option Counterparties, are not part of the terms of the Convertible Notes and will not change the holders' rights under the Convertible Notes. REG Geismar, LLC's GOZone Bonds The Company assumed Dynamic Fuels’ GOZone bond obligation at the time of the purchase of Dynamic Fuels (see "Note 5 - Acquisitions"). In connection with the acquisition from Tyson Foods, the Company agreed to reimburse Tyson Foods for any amounts payable by Tyson relating to an irrevocable direct-pay letter of credit (Old Letter of Credit), which was obtained by Tyson to pay for the principal and interest on Dynamic Fuels' GOZone Bonds. Tyson's total obligation under the Old Letter of Credit amounted to $101,315 , which represents the sum of the outstanding $100,000 principal amount of the GOZone Bonds plus $1,315 of interest at the date of the acquisition. On July 8, 2014, REG Geismar and Bank of America entered into a Reimbursement Agreement, dated as of the same date (Reimbursement Agreement), and Bank of America issued a letter of credit (Substitute Letter of Credit) to the trustee for the GOZone Bonds, in substitution for the irrevocable direct-pay letter of credit (Old Letter of Credit) held by Tyson Foods. The Substitute Letter of Credit is in the stated amount of $101,315 . REG Geismar’s repayment obligations under the Reimbursement Agreement are secured by a $101,315 certificate of deposit established by REG Capital, LLC, or REG Capital, which was pledged by REG Capital to Bank of America. This certificate of deposit is recorded as restricted cash in non-current assets of the Consolidated Balance Sheets. The Substitute Letter of Credit expired on July 8, 2015 and was extended to July 8, 2016. In the event that the expiration date of the Substitute Letter of Credit is not extended or a new letter of credit is not issued in substitution for the Substitute Letter of Credit, holders of the Bonds are required to tender their Bonds for repurchase and the trustee for the Bonds is required pursuant to the terms of the indenture governing the Bonds to draw down the Substitute Letter of Credit to fund the repurchase of the Bonds. The Substitute Letter of Credit requires that the Bonds remain in the daily or weekly interest rate mode. REG Marketing & Logistics Group, LLC & REG Services Group, LLC The Company’s revolving debt at December 31 are as follows: 2015 2014 Total revolving loans (current) $ 23,149 $ 16,679 Maximum remaining available to be borrowed under revolving line of credit $ 23,067 $ 20,719 We currently have a revolving credit agreement with the lenders thereto and Wells Fargo Capital Finance, LLC, as agent, which we refer to as the Wells Fargo Revolver. The Wells Fargo Revolver provides for the extension of revolving loans in an aggregate principal amount not to exceed $60,000 , based on eligible inventory, accounts receivable, biodiesel tax credits of the subsidiary borrowers and the inventory of certain affiliates. As of December 31, 2015 , our available borrowing capacity under the Wells Fargo Revolver was $46,216 of which $23,149 was outstanding, leaving $23,067 in availability. The Wells Fargo Revolver has a stated maturity date of December 23, 2016. There is a contractual requirement for daily net settlement through a sweep from the Company’s cash account, as such the Company presented the Revolver activity in the financing section of the Consolidated Statement of Cash Flows on a net basis. Amounts borrowed under the Wells Fargo Revolver bear interest, in the case of LIBOR rate loans, at a per annum rate equal to the LIBOR rate plus the LIBOR Rate Margin (as defined), which may range from 2.50 to 4.25 percent, based on the Quantity Average Excess Availability Amount (as defined). The LIBOR Rate Margin is subject to reduction or increase depending on the amount available for borrowing under the new revolving credit agreement. The Wells Fargo Revolver contains various loan covenants that restrict each subsidiary borrower’s ability to take certain actions, including restrictions on incurrence of indebtedness, creation of liens, mergers or consolidations, dispositions of assets, repurchase or redemption of capital stock, making certain investments, entering into certain transactions with affiliates or changing the nature of the subsidiary’s business. In addition, the subsidiary borrowers are required to maintain a Fixed Charge Coverage Ratio (as defined in the Wells Fargo Revolver) of at least 1.0 to 1.0 and to have Excess Availability (as defined in the Wells Fargo Revolver) of at least $6,000 . The Wells Fargo Revolver is secured by the subsidiary borrowers’ membership interests and substantially all of their assets, and the inventory of REG Albert Lea, LLC, REG Houston, LLC, REG New Boston, LLC, and REG Geismar, LLC subject to a $25,000 limitation. Maturities of the term debt, including the convertible debt, are as follows for the years ending December 31: 2016 $ 5,206 2017 5,248 2018 15,718 2019 128,091 2020 929 Thereafter 101,370 Total 256,562 Less: current portion 5,206 $ 251,356

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES Income tax benefit (expense) for the years ended December 31 is as follows: 2015 2014 2013 Current income tax benefit (expense) Federal $ — $ — $ 2,432 State — — 2,492 Foreign (225 ) — — (225 ) — 4,924 Deferred income tax benefit (expense) Federal 24,151 (14,112 ) 15,297 State 9,736 1,420 3,736 Foreign 1,035 9 — Net operating loss carryforwards created 88,110 61,640 48,024 123,032 48,957 67,057 Income tax benefit (expense) before valuation allowances 122,807 48,957 71,981 Deferred tax valuation allowances (114,106 ) (52,529 ) (76,916 ) Income tax benefit (expense) $ 8,701 $ (3,572 ) $ (4,935 ) A reconciliation of the reported amount of income tax expense to the amount computed by applying the statutory federal income tax rate to earnings from continuing operations before income taxes is as follows: 2015 2014 2013 U.S. Federal income tax expense at a statutory rate of 35 percent $ 56,144 $ (30,139 ) $ (66,955 ) State taxes, net of federal income tax benefit 12,777 5,119 6,905 Tax position on government incentives 85,423 76,662 131,829 Goodwill impairment (35,062 ) — — Bargain purchase gain 1,875 — — Other 1,650 (2,685 ) 202 Total (expense) benefits for income taxes before valuation allowances 122,807 48,957 71,981 Valuation allowances (114,106 ) (52,529 ) (76,916 ) Total benefit (expense) for income taxes $ 8,701 $ (3,572 ) $ (4,935 ) The Company had historically included revenue from certain government incentive payments in taxable income on its federal and state income tax returns. In connection with the U.S. Internal Revenue Service audits of the 2011 and 2010 years, the Company proposed that these government incentive payments should be excluded from taxable income. The U.S. Internal Revenue Service accepted this position and on August 1, 2013, the Company received notification from the congressional Joint Committee on Taxation approving the audit results and associated refund claim. Therefore, based on information obtained in connection with these audits, the Company changed its position related to these government incentive payments to exclude them from taxable income for years 2008 through the current year. The majority of this reduction increased the Company's net operating loss carry forwards available to offset future taxable income rather than resulting in a refund of taxes previously paid. As a result of excluding these government incentive payments, the Company currently has cumulative losses in recent years and initially established a valuation allowance in 2013 to reduce its total deferred tax assets to the amount more-likely-than-not to be realized. In 2015 the Company had a non-cash impairment charge for goodwill of $175,028 , of which $100,177 was not deductible for tax purposes. A $35,062 tax impact related to the non-deductible portion of the goodwill impairment charge is reflected in the tax reconciliation above. In November 2015, the Financial Accounting Standards Board issued ASU 2015-17, “Balance Sheet Classification of Deferred Taxes” , which states that, in a classified statement of financial position, an entity shall classify deferred tax assets and liabilities as noncurrent amounts. The Company early adopted ASU 2015-17 effective December 31, 2015 on a prospective basis in order to simplify the presentation of deferred income taxes by eliminating the need to separate deferred incomes tax liabilities and assets into current and non-current amounts in a classified balance sheet. The Company’s prior period financial statements have not been retrospectively adjusted. The Company’s early adoption of ASU 2015-17 resulted in a reclassification of the Company’s current deferred tax liability to the non-current deferred tax liability in the Company’s Consolidated Balance Sheets as of December 31, 2015. If the Company had retrospectively adopted the standard, the 2014 current deferred tax liability would have been zero instead of the $14,899 reported, and the non-current deferred tax liability would have been $21,804 instead of the $6,905 reported. The tax effects of temporary differences that give rise to the Company’s deferred tax assets and liabilities at December 31 are as follows: 2015 2014 Current Noncurrent Current Noncurrent Deferred Tax Assets: Goodwill $ — $ 39,172 $ — $ 13,716 Net operating loss carryforwards — 243,865 — 154,020 Tax credit carryforwards — 1,597 — 1,597 Start-up costs — 988 — 1,111 Stock-based compensation — 4,703 — 3,469 Terminal leases — 3,859 — 4,229 Capitalized research and development — 8,096 — 3,711 Accrued compensation — 2,546 3,422 — Inventory capitalization — 2,046 1,600 — Allowance for doubtful accounts — 567 931 — Other — 1,569 56 1,474 Deferred tax assets — 309,008 6,009 183,327 Deferred Tax Liabilities: Prepaid expenses — (1,338 ) (1,239 ) — Property, plant and equipment — (65,398 ) — (53,133 ) Intangibles — (3,909 ) — (3,018 ) Deferred revenue — — (4,443 ) — Convertible debt — (3,626 ) (4,599 ) — Unrealized gain (loss) on available for sale investments — (1,752 ) (5,767 ) — Other — (2,007 ) (527 ) (1,867 ) Deferred tax liabilities — (78,030 ) (16,575 ) (58,018 ) Net deferred tax assets (liabilities) — 230,978 (10,566 ) 125,309 Valuation allowance — (250,164 ) (4,333 ) (132,214 ) Net deferred taxes $ — $ (19,186 ) $ (14,899 ) $ (6,905 ) At December 31, 2015 , the Company has recorded a deferred tax asset of $243,865 reflecting the benefit of federal, state and foreign net operating loss carry-forwards. Federal net operating loss carry-forward totals $617,698 and will begin to expire in 2028 , while the amount and expiration dates of state net operating losses vary by jurisdiction. Changes in ownership of the Company, as defined by Section 382 of the Internal Revenue Code of 1986, as amended, may limit the utilization of federal and state net operating losses and credit carry forwards in any one year. The Company has performed a study to determine the impact of changes in ownership on utilization of carry forward attributes, the results of which have been incorporated into our financial statements. As discussed above, in evaluating available evidence around the recoverability of net deferred tax assets, the Company considers, among other factors, historical financial performance, expectation of future earnings, length of statutory carry forward periods and ability to carry back losses to prior periods, experience with operating loss and tax credit carry forwards not expiring unused, tax planning strategies and timing for the of reversals of temporary differences. In evaluating losses, management considers the nature, frequency and severity of losses in light of the conditions giving rise to those losses. As a result of the above described tax policy of excluding government incentive payments from taxable income, the Company currently has cumulative losses in recent years and has established a valuation allowance to reduce its total deferred tax assets to the amount more-likely-than-not to be realized. Activity regarding the valuation allowance for deferred tax assets was as follows: 2015 2014 2013 Beginning of year balance $ 136,547 $ 76,916 $ — Changes in valuation allowance charged to income 114,106 52,529 76,916 Foreign currency translation (773 ) — — Acquisition 284 7,102 — End of year balance $ 250,164 $ 136,547 $ 76,916 The Company analyzes filing positions in all of the federal and state jurisdictions where it is required to file income tax returns, and all open tax years in these jurisdictions to determine if it has any uncertain tax positions on any of its income tax returns. An uncertain tax position represents the Company’s expected treatment of a tax position taken in a filed tax return, or planned to be taken in a tax return not yet filed, that has not been reflected in measuring income tax expense for financial reporting purposes. The Company does not recognize income tax benefits associated with uncertain tax positions where it is determined that it is not more-likely-than-not, based on the technical merits, that the position will be sustained upon examination. A reconciliation of the total amounts of unrecognized tax benefits at December 31 is as follows: 2015 2014 2013 Beginning and end of year balance $ 1,900 $ 1,900 $ 1,900 The amount of unrecognized tax benefits that would affect the effective tax rate if the tax benefits were recognized was $0 , $0 and $1,428 at December 31, 2015 , 2014 and 2013 , respectively. The remaining liability for unrecognized tax benefits is related to tax positions for which there is a related deferred tax asset. The Company does not believe it is reasonably possible that the amounts of unrecognized tax benefits existing as of December 31, 2015 will significantly increase or decrease over the next twelve months. Interest and penalties related to unrecognized tax benefits are recognized as a component of income tax expense. The Company has not recorded any such amounts in the periods presented. The U.S. Internal Revenue Service has examined the Company's federal income tax returns through 2008, as well as 2010 and 2011. All other years are subject to examination, while various state income tax returns also remain subject to examination by state taxing authorities. The Company considers its foreign earnings of non US subsidiaries to be permanently reinvested. Any amount would become taxable upon a repatriation of assets from the subsidiary or a sale or liquidation of the subsidiary. The Company has not made a provision for U.S. or additional foreign withholding taxes. The Company currently has a tax basis in excess of financial reporting basis on its foreign subsidiaries and no unrecognized deferred tax liabilities.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	STOCK-BASED COMPENSATION On October 26, 2011, the stockholders approved the 2009 Stock Incentive Plan (the 2009 Plan) which authorizes up to 4,160,000 shares of Company Common Stock to be issued for the award of restricted stock, restricted stock units (RSU’s) and stock appreciation rights (SAR’s) at the discretion of the Company Board as compensation to employees, consultants of the Company and to non-employee directors. Under the 2009 Plan, an additional 1,800,000 shares, or 5,960,000 shares in total, are reserved for issuance as approved by shareholders on May 15, 2014. The expense is measured at the grant-date fair value of the award and recognized as compensation expense on a straight-line basis over the service period, which is the vesting period. There was no cash flow impact resulting from the grants of these awards. The 2009 Plan is generally protected from anti-dilution via adjustments for any stock dividends, stock split, combination or other recapitalization. The Company recorded stock-based compensation expense of $5,161 , $5,883 and $5,416 for the years ended December 31, 2015 , 2014 and 2013 , respectively. The stock-based compensation costs were included as a component of selling, general and administrative expenses. At December 31, 2015 , there was $6,438 of unrecognized compensation expense related to unvested awards, which is expected to be recognized over a period of approximately 3.2 years . Restricted Stock Units The following table summarizes information about the Company’s Common Stock RSU’s granted, vested, exercised and forfeited: Number of Awards Weighted Average Issue Price Awards outstanding - January 1, 2013 505,616 $17.14 Issued 204,183 $11.96 Vested and restriction lapsed (192,190 ) $15.72 Forfeited (16,681 ) $9.98 Awards outstanding - December 31, 2013 500,928 $15.81 Issued 257,030 $10.97 Vested and restriction lapsed (124,906 ) $10.42 Forfeited (16,658 ) $10.95 Awards outstanding - December 31, 2014 616,394 $15.00 Issued 339,280 $9.34 Vested and restriction lapsed (295,089 ) $9.36 Forfeited (22,687 ) $10.56 Awards outstanding - December 31, 2015 637,898 $12.87 The RSU’s convert into one share of common stock upon vesting. RSU’s cliff vest at the earlier of expressly provided service or performance conditions. The service period for these RSU awards, excluding those issued to the Company’s Board of Directors ( one year ) and certain executive management ( four year), is a three year period from the grant date. The performance conditions provide for accelerated vesting upon various conditions including a change in control or other common stock liquidity events. Stock Appreciation Rights The following table summarizes information about SAR’s granted, forfeited, vested and exercisable: Number of SAR’s Weighted Average Exercise Price Weighted Average Contractual Term SAR's outstanding - January 1, 2013 1,053,845 $9.47 Granted 335,057 $12.85 Exercised (5,106 ) $8.92 Forfeited (10,727 ) $10.85 SAR's outstanding - December 31, 2013 1,373,069 $10.28 8.6 years Granted 449,225 $11.73 Exercised (435 ) $7.37 Forfeited (12,557 ) $11.57 SAR's outstanding - December 31, 2014 1,809,302 $10.63 8.1 years Granted 655,855 $9.47 Exercised (14,470 ) $9.21 Forfeited (54,561 ) $10.30 SAR's outstanding - December 31, 2015 2,396,126 $10.33 7.6 years SAR's exercisable - December 31, 2015 758,952 $13.69 7.6 years SAR's expected to vest - December 31, 2015 1,479,586 $10.40 7.6 years The SAR’s vest 25% annually on each of the four anniversary dates following the grant date and expire after ten years . The fair value of each SAR grant is estimated using the Black-Scholes option-pricing model as set forth in the table below: 2015 2014 2013 The weighted average fair value of stock appreciation rights issued (per unit) $3.33 - $3.90 $4.18 - $4.93 $2.54 - $6.51 Dividend yield —% —% —% Weighted average risk-free interest rate 1.4% - 1.6% 1.5% - 1.8% 0.7% - 1.8% Weighted average expected volatility 40% 40% 40% Expected life in years 6.25 6.25 6.25 Stock Options The following table summarizes information about Common Stock options granted, exercised, forfeited, vested and exercisable: Number of Options Weighted Average Exercise Price Weighted Average Contractual Term Options outstanding - January 1, 2013 87,026 $23.75 3.6 years Granted — $— Exercised — $— Forfeited — $— Options outstanding - December 31, 2013 87,026 $23.75 2.6 years Granted — $— Exercised — $— Forfeited — $— Options outstanding - December 31, 2014 87,026 $23.75 1.6 years Granted — $— Exercised — $— Forfeited — $— Options outstanding - December 31, 2015 87,026 $23.75 0.6 years Options exercisable - December 31, 2015 87,026 $23.75 0.6 years All stock options that remain outstanding are fully vested and exercisable. There was no intrinsic value of options granted, exercised or outstanding during the periods presented.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2015
Related Party Transactions [Abstract]
Related Party Transactions	RELATED PARTY TRANSACTIONS Related parties include certain investors as well as entities in which the Company has an equity method investment or an investment combined with a management and operational services agreement (or MOSA) or board seat. Investors defined as related parties include (i) the investor having ten percent or more ownership, including convertible preferred stock, in the Company or (ii) the investor holding a board seat on the Company Board. After the IPO, the number of related parties decreased due to the dilution of ownership of prior investors as well as the reduction of the number of board seats on the Company Board held by related party investors. The Company will report related party transactions before and after the IPO based on the related party characteristics mentioned above. Summary of Related Party Transactions - Consolidated Statements of Operations 2015 2014 2013 Cost of goods sold - Biomass-based diesel (a) $ 4,542 $ 42,622 $ 49,358 Selling, general and administrative expenses (a) $ — $ 45 $ 37 Interest expense (a) $ — $ 7 $ 30 (a) Represents transactions with West Central prior to the Company's determination that West Central was no longer a related party. Summary of Related Party Balances - Consolidated Balance Sheets 2015 2014 Accounts receivable (a) $ — $ 36 Accounts payable (a) $ — $ 1,101 (a) Represents balances with West Central. West Central Cooperative The Company purchases once-refined soybean oil from West Central Cooperative (West Central) and is required to pay interest for amounts owed on extended trade terms. The Company also had biomass-based diesel and co-product sales to West Central. West Central leases the land under the Company’s production facility at Ralston, Iowa to the Company at an annual cost of one dollar. The Company is responsible for the property taxes, insurance, utilities and repairs for the facility relating to this lease. The lease has an initial term of twenty years and the Company has options to renew the lease for an additional thirty years. In 2006, the Company executed an asset use agreement with West Central to provide for the use of certain assets, such as office space, maintenance equipment and utilities. The agreement requires the Company to pay West Central its proportionate share of certain costs incurred by West Central. This agreement has the same term as the land lease. During February 2012, the Company renegotiated the asset use agreement. The new agreement provides for the use of certain assets, such as buildings, equipment and utilities, which will be charged to the Company based on fixed and variable components. The Company reassesses its related parties at reporting dates and has determined that West Central Cooperative (West Central) is no longer a related party as West Central no longer holds ten percent or more of the Company’s outstanding Common Stock nor a board seat on the Company board.

Operating Leases

Operating Leases	12 Months Ended
	Dec. 31, 2015
Leases, Operating [Abstract]
Operating Leases	OPERATING LEASES The Company leases certain land and equipment under operating leases. Total rent expense under operating leases was $19,814 , $17,498 and $12,549 for the years ended December 31, 2015 , 2014 and 2013 , respectively. For each of the next five calendar years and thereafter, future minimum lease payments under operating leases that have initial or remaining noncancelable lease terms in excess of one year are as follows: Total Payments 2016 $ 18,339 2017 14,164 2018 13,515 2019 12,219 2020 10,749 Thereafter 50,449 Total minimum payments $ 119,435 The Company's leases consist primarily of access to distribution terminals, biomass-based diesel storage facilities, railcars and vehicles. At the end of the lease term the Company, generally, has the option to (a) return the leased equipment to the lessor, (b) purchase the property at its then fair value or (c) renew its lease at the then fair rental value on a year-to-year basis or for an agreed upon term. Certain leases allow for adjustment to minimum rentals in future periods as determined by the Consumer Price Index.

Derivative Instruments

Derivative Instruments	12 Months Ended
	Dec. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	DERIVATIVE INSTRUMENTS The Company has entered into heating oil and soybean oil futures, swaps and options (commodity derivative contracts) to reduce the risk of price volatility related to anticipated purchases of feedstock raw materials and to protect gross profit margins from potentially adverse effects of price volatility on biomass-based diesel sales where prices are set at a future date. All of the Company’s derivatives are recorded at fair value on the Consolidated Balance Sheets. Unrealized gains and losses on commodity futures, swaps and options contracts used to risk-manage feedstock purchases or biomass-based diesel inventory are recognized as a component of biomass-based diesel costs of goods sold reflected in current results of operations. At December 31, 2015 , the net notional volumes of heating oil and soybean oil covered under the open commodity derivative contracts were 47.8 million gallons and 40.1 million pounds, respectively. The Company offsets the fair value amounts recognized for its commodity derivative contracts with cash collateral with the same counterparty under a master netting agreement. The net position is presented within Prepaid expenses and other assets in the Consolidated Balance Sheets, see "Note 10 – Other Assets". As of December 31, 2015 , the Company posted $5,638 of collateral associated with its commodity-based derivatives with a net asset position of $10,097 . The following tables provide details regarding the Company’s derivative financial instruments: December 31, 2015 December 31, 2014 Assets Liabilities Assets Liabilities Gross amounts of commodity derivative contracts recognized at fair value $ 4,644 $ 185 $ 14,901 $ 205 Cash collateral 5,638 — 2,870 4,628 Total gross amount recognized 10,282 185 17,771 4,833 Gross amounts offset (185 ) (185 ) (4,833 ) (4,833 ) Net amount reported in the Consolidated Balance Sheets $ 10,097 $ — $ 12,938 $ — The following table sets forth the pre-tax gains (losses) included in the Consolidated Statements of Operations: Location of Gain (Loss) 2015 2014 2013 Commodity derivatives Cost of goods sold – Biomass-based diesel $ 35,983 $ 61,631 $ (5,656 )

Fair Value Measurement

Fair Value Measurement	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value Measurement	FAIR VALUE MEASUREMENT The fair value hierarchy prioritizes the inputs used in measuring fair value as follows: • Level 1—Quoted prices for identical instruments in active markets. • Level 2—Quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-derived valuations, in which all significant inputs are observable in active markets. • Level 3—Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions. A summary of assets (liabilities) measured at fair value is as follows: As of December 31, 2015 Total Level 1 Level 2 Level 3 Commodity contract derivatives $ 4,459 $ 2,196 $ 2,263 $ — Contingent consideration for LS9 acquisition $ (7,590 ) — — (7,590 ) Contingent consideration for Dynamic Fuels acquisition $ (29,209 ) — — (29,209 ) Contingent consideration for Imperium acquisition $ (4,913 ) — — (4,913 ) $ (37,253 ) $ 2,196 $ 2,263 $ (41,712 ) As of December 31, 2014 Total Level 1 Level 2 Level 3 Money market funds $ 302 $ 302 $ — $ — Certificates of deposit $ 9,995 — 9,995 — Commercial notes/bonds $ 6,775 — 6,775 — Commodity contract derivatives $ 14,696 6,885 7,811 — Contingent consideration for LS9 acquisition $ (8,624 ) — — (8,624 ) Contingent consideration for Dynamic Fuels acquisition $ (30,695 ) — — (30,695 ) $ (7,551 ) $ 7,187 $ 24,581 $ (39,319 ) The following is a reconciliation of the beginning and ending balances for liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) during the years ended as follows: Contingent Consideration for LS9 Acquisition Contingent Consideration for Dynamic Fuels Acquisition Contingent Consideration for Imperium Acquisition Balance at January 1, 2013 and December 31, 2013 $ — $ — $ — Issuance of contingent consideration for acquisitions 17,050 28,900 — Change in estimates included in earnings (8,426 ) 1,795 — Settlements — — — Balance at December 31, 2014 8,624 30,695 — Issuance of contingent consideration for acquisitions — — 5,000 Change in estimates included in earnings (1,034 ) 675 — Settlements — (2,161 ) (87 ) Ending balance - December 31, 2015 $ 7,590 $ 29,209 $ 4,913 The Company used the following methods and assumptions to estimate fair value of its financial instruments: Marketable securities : The fair value of marketable securities, which include certificates of deposit and commercial notes/bonds are obtained using quoted prices for similar assets or liabilities in active markets; quoted prices for identical or similar assets in markets that are not active; and inputs other than quoted prices, e.g., interest rates and yield curves. The Company utilizes a pricing service to assist in obtaining fair value pricing for the majority of this investment portfolio. Commodity contract derivatives: The instruments held by the Company consist primarily of futures contracts, swap agreements, purchased put options and written call options. The fair value of contracts based on quoted prices of identical assets in an active exchange-traded market is reflected in Level 1. Contract fair value is determined based on quoted prices of similar contracts in over-the-counter markets and are reflected in Level 2. Contingent consideration for acquisitions: The fair value of the LS9 contingent consideration is determined using an expected present value technique. Expected cash flows are determined using the probability weighted-average of possible outcomes that would occur should achievement of certain milestones related to the development and commercialization of products from LS9’s technology occur. There is no observable market data available to use in valuing the contingent consideration; therefore, the Company developed its own assumptions related to the expected future delivery of product enhancements to estimate the fair value of these liabilities. An 8.0% discount rate is used to estimate the fair value of the expected payments. The fair value of the Dynamic Fuels contingent consideration is determined using an expected present value technique. Expected cash flows are determined using the probability weighted-average of possible outcomes that would occur based on the sales and volumes of renewable hydrocarbon diesel at the REG Geismar's production facility. A 5.8% discount rate is used to estimate the fair value of the expected payments. The fair value of the Imperium contingent consideration was estimated based on an income approach. Expected earnouts are determined as total present value of the possible outcomes at a discount rate of 10% should the achievement of the production and sales volume at the REG Grays Harbor facility occur post acquisition as well as whether the biodiesel mixture excise tax credit is reinstated. Debt and lines of credit: The fair value of long-term debt and lines of credit was established using discounted cash flow calculations and current market rates reflecting Level 2 inputs. The estimated fair values of the Company’s financial instruments, which are not recorded at fair value are as follows as of December 31: 2015 2014 Asset (Liability) Carrying Amount Estimated Fair Value Asset (Liability) Carrying Amount Estimated Fair Value Financial Liabilities: Debt and lines of credit $ (279,711 ) $ (275,123 ) $ (269,608 ) $ (270,331 )

Net Income (Loss) Per Share

Net Income (Loss) Per Share	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Net Income (Loss) Per Share	NET INCOME (LOSS) PER SHARE Basic net income per common share is presented in conformity with the two-class method required for participating securities. Participating securities include, or have included, Series A Preferred Stock, Series B Preferred Stock and RSU's. Under the two-class method, net income is reduced for distributed and undistributed dividends earned in the current period. The remaining earnings are then allocated to Common Stock and the participating securities. The Company calculates the effects of participating securities on diluted earnings per share (EPS) using both the “if-converted or treasury stock” and "two-class" methods and discloses the method which results in a more dilutive effect. The effects of Common Stock options, warrants, stock appreciation rights and convertible notes on diluted EPS are calculated using the treasury stock method unless the effects are anti-dilutive to EPS. The following potentially dilutive weighted average securities were excluded from the calculation of diluted net income per share attributable to common stockholders during the periods presented as the effect was anti-dilutive: Year Ended December 31, 2015 2014 2013 Options to purchase common stock 87,026 87,026 87,026 Stock appreciation rights 2,072,130 1,400,824 1,030,926 Warrants to purchase common stock — 17,916 — Convertible notes 10,838,218 6,295,075 — Total 12,997,374 7,800,841 1,117,952 The following table presents the calculation of diluted net income per share for the years ended December 31, 2015 , 2014 and 2013 (in thousands, except share and per share data): 2015 2014 2013 Net income (loss) attributable to the Company's common stockholders - Basic $ (151,392 ) $ 81,620 $ 165,254 Plus: distributed dividends to Preferred Stockholders — 40 2,055 Plus (less): effect of participating securities — (418 ) (2,051 ) Net income (loss) attributable to the Company's common stockholders - Diluted $ (151,392 ) $ 81,242 $ 165,258 Shares: Weighted-average shares outstanding - Basic 43,958,803 40,740,411 33,045,164 Adjustment to reflect stock appreciation right conversions — 9,502 7,065 Adjustment to reflect warrants to purchase common stock — — 650 Weighted-average shares outstanding - Diluted 43,958,803 40,749,913 33,052,879 Net income (loss) per share attributable to common stockholders - Diluted $ (3.44 ) $ 1.99 $ 5.00

Reportable Segments and Geograp

Reportable Segments and Geographic Information	12 Months Ended
	Dec. 31, 2015
Segment Reporting [Abstract]
Reportable Segments and Geographic Information	REPORTABLE SEGMENTS AND GEOGRAPHIC INFORMATION The Company reports its reportable segments based on products and services provided to customers. The Company re-assesses its reportable segment on an annual basis. During the fourth quarter of 2015, the Company determined that as activities surrounding its renewable chemicals business increase, it changed the composition of its operating segments from two reportable segments to three reportable segments by presenting Renewable Chemicals separate from Biomass-based diesel. The new reportable segments generally align the Company's external financial reporting segments with its new internal operating segments, which are based on its internal organizational structure, operating decisions, and performance assessment. As such, our reportable segments at December 31, 2015 include Biomass-based diesel, Services, Renewable Chemicals and Corporate and other activities. The accounting policies of the segments are the same as those described in the summary of significant accounting policies. All prior period disclosures below have been recast to present results on a comparable basis. The Biomass-based diesel segment processes waste vegetable oils, animal fats, virgin vegetable oils and other feedstocks and methanol into biomass-based diesel. The Biomass-based diesel segment also includes the Company’s purchases and resale of biomass-based diesel produced by third parties. Revenue is derived from the purchases and sales of biomass-based diesel, RINs and raw material feedstocks acquired from third parties, sales of biomass-based diesel produced under toll manufacturing arrangements with third party facilities, sales of processed biomass-based diesel from Company facilities, related by-products and renewable energy government incentive payments, in the U.S. and internationally. The Services segment offers services for managing the construction of biomass-based diesel production facilities and managing ongoing operations of third party plants and collects fees related to the services provided. The Company does not allocate items that are of a non-operating nature or corporate expenses to the business segments. Revenues are recorded by the Services segment at cost. The Renewable Chemicals segment consists of research and development activities involving the production of renewable chemicals, additional advanced biofuels and other products from the Company's proprietary microbial fermentation process and the operations of a demonstration scale facility located in Okeechobee, Florida. No revenues were recorded by the Renewable Chemicals segment during 2015 or 2014. The Corporate and Other segment includes trading activities related to petroleum-based heating oil and diesel fuel as well as corporate activities, which consist of corporate office expenses such as compensation, benefits, occupancy and other administrative costs, including management service expenses. Corporate and other also includes income/(expense) not associated with the reportable segments, such as corporate general and administrative expenses, shared service expenses, interest expense and interest income, all reflected on an accrual basis of accounting. In addition, corporate and other includes cash and other assets not associated with the reportable segments, including investments. Intersegment revenues are reported by the Services and Corporate and Other segments. The following table represents the significant items by reportable segment for the results of operations for the years ended December 31, 2015 , 2014 and 2013 : 2015 2014 2013 Net sales: Biomass-based Diesel (includes Petrotec's net sales of $145,039, $3,563 and $0, respectively) $ 1,326,452 $ 1,264,850 $ 1,500,580 Services 102,731 85,149 56,121 Corporate and other 68,984 11,940 — Intersegment revenues (110,823 ) (88,108 ) (58,563 ) $ 1,387,344 $ 1,273,831 $ 1,498,138 Income (loss) before income taxes Biomass-based diesel (includes Petrotec's losses of $(1,643), $(337) and $0, respectively) $ (100,152 ) $ 104,136 $ 201,114 Services 6,323 6,980 3,851 Renewable Chemicals (52,728 ) (12,252 ) — Corporate and other (13,854 ) (12,754 ) (13,664 ) $ (160,411 ) $ 86,110 $ 191,301 Depreciation and amortization expense, net: Biomass-based diesel (includes Petrotec's amounts of $3,259, $0, $0, respectively) $ 22,799 $ 13,497 $ 8,611 Services 302 204 120 Renewable Chemicals 1,413 1,293 — Corporate and other 1,362 802 511 $ 25,876 $ 15,796 $ 9,242 Cash paid for purchases of property, plant and equipment: Biomass-based diesel (includes Petrotec's amounts of $1,816, $0, $0, respectively) $ 59,859 $ 52,846 $ 36,770 Services 1,510 643 504 Renewable Chemicals 672 532 — Corporate and other 2,436 6,142 1,779 $ 64,477 $ 60,163 $ 39,053 2015 2014 Goodwill: Biomass-based diesel $ — $ 137,348 Services 16,080 16,080 Renewable Chemicals — 34,847 $ 16,080 $ 188,275 Assets: Biomass-based diesel (including Petrotec's assets of $45,471 and $56,960) $ 1,048,923 $ 1,150,851 Services 60,308 46,560 Renewable Chemicals 23,872 59,134 Corporate and other 308,782 235,823 Intersegment eliminations $ (218,265 ) $ (124,632 ) $ 1,223,620 $ 1,367,736 Geographic Information: The following geographic data include net sales attributed to the countries based on the location of the subsidiary making the sale and long-lived assets based on physical location. Long-lived assets represent the net book value of property, plant and equipment. Sales and long-lived assets of the Company's investment in Petrotec comprise substantially all of the amounts categorized as Foreign in the table below. 2015 2014 2013 Net sales: United States $ 1,242,305 $ 1,270,268 $ 1,498,138 Foreign 145,039 3,563 — $ 1,387,344 $ 1,273,831 $ 1,498,138 2015 2014 Long-lived assets: United States $ 553,987 $ 468,170 Foreign 20,597 25,026 $ 574,584 $ 493,196

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES The Company is involved in legal proceedings in the normal course of business. The Company currently believes that any ultimate liability arising out of such proceedings will not have a material adverse effect on the Company’s financial position, results of operations or cash flows. The Company has entered into contracts for supplies of hydrogen, nitrogen and utilities for the REG Geismar production facility and natural gas for REG Albert Lea. The following table outlines the minimum take or pay requirement related to the purchase of hydrogen, nitrogen, utilities and natural gas. 2016 $ 3,857 2017 3,857 2018 3,784 2019 3,748 2020 3,297 Thereafter 12,733 Total $ 31,276 As of December 31, 2015 , REG Geismar relies on one supplier to provide hydrogen necessary to execute the production process. Any disruptions to the hydrogen supply during production from this supplier will result in the shutdown of the REG Geismar plant operations. The Company is currently seeking additional hydrogen suppliers for the REG Geismar facility.

Supplemental Quarterly Informat

Supplemental Quarterly Information (Unaudited)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Supplemental Quarterly Information (Unaudited)	SUPPLEMENTAL QUARTERLY INFORMATION (UNAUDITED) The following table represents the significant items for the results of operations on a quarterly basis for the years ended December 31, 2015 and 2014 : Three Months Three Months Three Months Three Months Revenues $ 230,918 $ 373,762 $ 394,856 $ 387,808 Gross profit (loss) (16,195 ) 15,907 4,405 106,426 Selling, general, and administrative expenses including research and development expense 20,535 19,749 21,995 27,969 Impairment of goodwill — — — 175,028 Loss from operations (36,730 ) (3,842 ) (17,590 ) (96,571 ) Other income (expense), net (2,471 ) 972 869 (5,048 ) Net loss attributable to the Company (38,107 ) (2,001 ) (15,675 ) (95,609 ) Net loss per share attributable to common stockholders - basic (0.86 ) (0.05 ) (0.36 ) (2.18 ) Net loss per share attributable to common stockholders - diluted (0.86 ) (0.05 ) (0.36 ) (2.18 ) Three Months Three Months Three Months Three Months Revenues $ 219,040 $ 332,918 $ 384,258 $ 337,615 Gross profit 11,564 15,151 22,715 111,182 Selling, general, and administrative expenses including research and development expense 13,527 15,627 16,707 29,244 Income (loss) from operations (1,963 ) (476 ) 6,008 81,938 Other income (expense), net (503 ) (436 ) (1,684 ) 3,226 Net income (loss) attributable to the Company (2,359 ) 11,007 4,572 69,391 Net income (loss) per share attributable to common stockholders - basic (0.05 ) 0.27 0.11 1.61 Net income (loss) per share attributable to common stockholders - diluted (0.06 ) 0.27 0.11 1.61 The results of operations for the three months ended December 31, 2015 reflect a goodwill impairment of $175,028 (before tax) and net benefit from the reinstatement of the BTC of $95,008 . Refer to Note 2 for more details. The results of operations for the three months ended December 31, 2014 reflected the net benefit from the reinstatement of the BTC of $78,781 .

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS On February 1, 2016, the Company signed an asset purchase agreement with Sanimax Energy, LLC ("Sanimax") to acquire Sanimax’s 20 million gallon nameplate capacity biodiesel refinery located in DeForest, Wisconsin. Under the asset purchase agreement, REG will pay Sanimax approximately $11,000 in cash and will issue 500,000 shares of REG common stock in exchange for the biorefinery and related assets. REG will also pay Sanimax up to an additional $5,000 in cash over a period of up to seven years after closing based on the volume of biodiesel produced at the plant, which will be re-named REG Madison, LLC. Sanimax operates a grease processing facility at the same location, although that facility is not part of the acquisition. The transaction is subject to customary closing conditions. On March 5, 2016, the Company's board of directors approved a repurchase program of up to $50,000 of the Company's shares of common stock and/or convertible notes, in effect through March 5, 2018. Under the program, REG may repurchase shares or bonds from time to time in open market transactions, privately negotiated transactions or by other means. The timing and amount of repurchase transactions will be determined by the Company's management based on its evaluation of market conditions, share price, bond price, legal requirements and other factors. The program may be suspended, modified or discontinued at any time without prior notice.

Summary of Significant Accoun34

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Basis of Consolidation	Basis of Consolidation The consolidated financial statements include the accounts of the Company, its wholly-owned subsidiaries, and entities which it controls. All intercompany balances and transactions have been eliminated for consolidated reporting purposes.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents consists of money market funds and demand deposits with financial institutions. The Company considers all highly liquid debt instruments purchased with an original maturity of three months or less to be cash equivalents.
Restricted Cash	Restricted Cash The Company segregates certain cash balances in accordance with lending arrangements and classified restricted cash between current and non-current assets based on the length of time of the restricted use.
Marketable Securities	Marketable Securities The Company’s marketable securities are classified as available-for-sale and are reported at fair value, with unrealized gains and losses, net of tax, recorded in accumulated other comprehensive income (loss). Realized gains or losses and declines in value judged to be other-than-temporary, if any, on available-for-sale securities are reported in other income, net. The Company evaluates the investments periodically for possible other-than-temporary impairment, specifically contemplating whether a sale of the securities is likely to occur before recovery of the entire amortized cost basis. The Company uses the specific identification method when securities are sold or reclassified out of accumulated other comprehensive income into earnings. The Company considers marketable securities maturing in less than one year as short-term. The Company has no outstanding marketable securities as of December 31, 2015 .
Accounts Receivable	Accounts Receivable Accounts receivable are carried at invoiced amount less allowance for doubtful accounts. Management estimates the allowance for doubtful accounts based on existing economic conditions, the financial conditions of customers, and the amount and age of past due accounts. Receivables are considered past due if full payment is not received by the contractual due date. Past due accounts are generally written off against the allowance for doubtful accounts only after reasonable collection attempts have been exhausted.
Inventories	Inventories Inventories are valued at the lower of cost or net realizable value. Cost is determined based on the first-in, first-out method.
Renewable Identification Numbers (RINs)	Renewable Identification Numbers (RINs) When the Company produces and sells a gallon of biomass-based diesel, 1.5 to 1.7 RINs per gallon are generated. RINs are used to track compliance with Renewable Fuel Standards (RFS2). RFS2 allows the Company to attach between zero and 2.5 RINs to any gallon of biomass-based diesel. As a result, a portion of the selling price for a gallon of biomass-based diesel is generally attributable to RFS2 compliance. However, RINs that the Company generates are a form of government incentive and not a result of the physical attributes of the biomass-based diesel production. Therefore, no cost is allocated to the RIN when it is generated, regardless of whether the RIN is transferred with the biomass-based diesel produced or held by the Company pending attachment to other biomass-based diesel production sales. In addition, the Company also obtains RINs from third parties who have separated the RINs from gallons of biomass-based diesel. From time to time, the Company holds varying amounts of these separated RINs for resale. RINs obtained from third parties are initially recorded at their cost and are subsequently revalued at the lower of cost or market as of the last day of each accounting period and the resulting adjustments are reflected in costs of goods sold for the period. The value of RINs obtained from third parties is reflected in “Prepaid expenses and other assets” on the consolidated balance sheet. The cost of goods sold related to the sale of these RINs is determined using the average cost method, while market prices are determined by RIN values, as reported by the Oil Price Information Service (OPIS). The Company records assets acquired and liabilities assumed through the exchange of non-monetary assets based on the fair value of the assets and liabilities acquired or the fair value of the consideration exchanged, whichever is more readily determinable.
Derivative Instruments	Derivative Instruments Derivatives are recorded on the balance sheet at fair value with changes in fair value recognized in current period earnings. The Company did not elect to use hedge accounting for all periods presented.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment is recorded at cost less accumulated depreciation. Maintenance and repairs are expensed as incurred. Depreciation expense is computed on a straight-line method based upon estimated useful lives of the assets. Estimated useful lives are as follows: Automobiles and trucks 5 years Computers and office equipment 5 years Office furniture and fixtures 7 years Machinery and equipment 5-30 years Leasehold improvements the lesser of the lease term or 30 years Buildings and improvements 30-40 years In April 2015, the Company experienced a fire at its Geismar facility, resulting in the shutdown of the facility. The Company estimated fixed assets of approximately $11,027 were impaired as a result of the fire. At December 31, 2015, the Company had received property proceeds of $11,027 from insurance for the property damage. In addition, the Company received approximately $4,293 related to the business interruption portion of the claim reimbursing a portion of lost margin during the repairs of the damages caused by the fire. The proceeds for business interruption were recorded as an increase in biomass-based diesel sales in the Company's Consolidated Statements of Operations. In September 2015, another fire occurred at the Geismar facility. The Company estimated fixed assets of approximately $1,414 were impaired by the September fire. The Company believes it is probable that it will recover all the net book value of the assets damaged by the fire under its insurance policies. As such, a receivable was recorded as an offset to the estimated impairment loss. No impact on earnings was recognized. As of December 31, 2015 , 2014 and 2013 , the Company capitalized interest incurred on debt during the construction of assets of $897 , $1,345 and $335 , respectively.
Goodwill	Goodwill Goodwill is tested for impairment annually on July 31 or when impairment indicators exist. Goodwill is allocated and tested for impairment by reporting units. The Company has determined that the reporting units subject to the 2015 goodwill impairment analysis were Biomass-based Diesel; Services; and Renewable Chemicals. The analysis is based on a comparison of the carrying value of the reporting unit to its fair value, determined utilizing both a discounted cash flow methodology and a market comparable methodology. The determination of whether or not the asset has become impaired involves a significant level of judgment in the assumptions underlying the approach used to determine the fair value of the Company’s reporting units, which represented a Level 3 asset measured at fair value on a nonrecurring basis subsequent to its original recognition. Changes in estimates of future cash flows caused by items such as unforeseen events or sustained unfavorable changes in market conditions could negatively affect the fair value of the reporting unit’s goodwill asset and result in an impairment charge.
Contingent Consideration for Acquisitions	Contingent Consideration for Acquisitions Contingent consideration in a business combination is established at the time of the acquisition (See "Note 5 - Acquisitions"). The contingent consideration is adjusted to fair value at each reporting period. The change in fair value is included in change in fair value of contingent consideration on the Consolidated Statements of Operations.
Impairment of Long-lived Assets	Impairment of Long-lived Assets The Company tests its long-lived assets for recoverability when events or circumstances indicate that its carrying amount may not be recoverable. Significant assumptions used in the undiscounted cash flow analysis, when it is required, include the projected demand for biomass-based diesel based on annual renewable fuel volume obligations under the Renewable Fuel Standards (RFS2), the Company's capacity to meet that demand, the market price of biomass-based diesel and the cost of feedstock used in the manufacturing process. For facilities under construction, estimates also include the capital expenditures necessary to complete construction of the plant and the projected costs of financing.
Investments	Investments The Company has made investments in several biofuels businesses. These investments are recorded at cost and assessed for impairment at each reporting period.
Unfavorable Lease Obligation	Unfavorable Lease Obligation The Company assumed ground and fixture leases as part of certain acquisitions which required the Company to pay above market rentals through the remainder of the lease terms. The unfavorable lease obligation is amortized over the contractual periods the Company is required to make rental payments under the leases.
Convertible Debt and Capped Call Transactions	Convertible Debt In June 2014, the Company issued $143,750 in convertible senior notes. Applicable authoritative accounting guidance requires that the conversion feature be assigned a fair value and that that feature reduce the initial recorded value of the liability component of the convertible senior notes. This conversion feature is recorded in equity on a net of tax basis. The discount on the liability component is being amortized through interest expense until the maturity date of June 15, 2019. See "Note 12 - Debt" for further descriptions of the transaction. Capped Call Transaction In connection with the issuance of the convertible senior notes, the Company entered into capped call transactions. The purchased capped call transactions were recorded as a reduction to common stock-additional paid-in-capital.
Share Repurchase Programs	Share Repurchase Programs In February 2015, the Company's board of directors approved a share repurchase program of up to $30,000 of the Company's shares of Common Stock. The program is in effect through October 31, 2016. Shares may be repurchased from time to time in open market transactions, privately negotiated transactions or by other means. The Company accounts for share repurchases using the cost method. Under this method, the cost of the share repurchase is recorded entirely in treasury stock, a contra equity account.
Foreign Currency Transactions and Translations	Foreign Currency Transactions and Translation The Company’s reporting and functional currency is U.S. dollars. Monetary assets and liabilities denominated in currencies other than U.S. dollars are remeasured into their respective functional currencies at exchange rates in effect at the balance sheet date. The resulting exchange gain or loss is included in the Company’s Consolidated Statements of Operations as foreign exchange gain (loss) unless the remeasurement gain or loss relates to an intercompany transaction that is of a long-term investment nature and for which settlement is not planned or anticipated in the foreseeable future. Gains or losses arising from translation of such transactions are reported as a component of accumulated other comprehensive income (loss) in the Company’s Consolidated Balance Sheets. The Company translates the assets and liabilities of its foreign subsidiaries from their respective functional currencies to U.S. dollars at the appropriate spot rates as of the balance sheet date. Generally, our foreign subsidiaries use the local currency as their functional currency. Changes in the carrying value of these assets and liabilities attributable to fluctuations in spot rates are recognized in foreign currency translation adjustment, a component of accumulated other comprehensive income (loss) in the Company’s Consolidated Balance Sheets. The other comprehensive loss amounts presented in the Company's Consolidated Statements of Comprehensive Income (Loss) and Consolidated Statements of Redeemable Preferred Stock and Equity mainly include the foreign currency translation adjustment resulting from translating the financial statements of Petrotec AG from Euros to US Dollars, the Company's functional currency.
Revenue Recognition	Revenue Recognition The Company recognizes revenues from the following sources: • the sale of biomass-based diesel and its co-products, as well as Renewable Identification Numbers (RINs) and raw material feedstocks, purchased or produced by the Company at owned manufacturing facilities and manufacturing facilities with which the Company has tolling arrangements; • the resale of biomass-based diesel, RINs and raw material feedstocks acquired from third parties; • the sale of petroleum-based heating oil and diesel fuel acquired from third parties, along with the sale of these items further blended with biodiesel produced at wholly owned facilities; • incentives received from federal and state programs for renewable fuels; and • fees received for the marketing and sales of biomass-based diesel produced by third parties and from managing operations of third party facilities. Biomass-based diesel, including RINs, and raw material feedstock revenues are recognized where there is persuasive evidence of an arrangement, delivery has occurred, the price has been fixed or is determinable and collectability can be reasonably assured. Fees received under toll manufacturing agreements with third parties are generally established as an agreed upon amount per gallon of biomass-based diesel produced. The fees are recognized where there is persuasive evidence of an arrangement, delivery has occurred, the price has been fixed or is determinable and collectability can be reasonably assured. Revenues associated with the governmental incentive programs are recognized when the amount to be received is determinable, collectability is reasonably assured and the sale of product giving rise to the incentive has been recognized. The Company received funds from the United States Department of Agriculture (USDA) in the amount of $624 , $600 and $2,813 for the years ended December 31, 2015 , 2014 and 2013 , respectively. The Company records amounts when it has received notification of a payment from the USDA or is in receipt of the funds and records the awards under the Program in "Biodiesel government incentives" as they are closely associated with the Company's biomass-based diesel production activities.
Freight	Freight Amounts billed to customers for freight are included in biomass-based diesel sales. Costs incurred for freight are included in costs of goods sold.
Advertising Costs	Advertising Costs Advertising costs are charged to expense as they are incurred.
Research and Development	Research and Development Research and development (R&D) costs are charged to expense as incurred. In process research and development (IPR&D) assets acquired in connection with acquisitions are recorded on the Consolidated Balance Sheets as intangible assets. Acquired IPR&D is initially assigned an indefinite life and is subject to impairment testing until the completion or abandonment of the associated R&D efforts. If abandoned, the carrying value of the IPR&D asset is expensed. Once the associated R&D efforts are completed, the carrying value of the IPR&D is reclassified as a finite-lived asset and is amortized over its useful life.
Employee Benefits Plan	Employee Benefits Plan The Company sponsors an employee savings plan under Section 401(k) of the Internal Revenue Code. The Company makes matching contributions equal to 50% of the participant’s pre-tax contribution up to a maximum of 6% of the participant’s eligible earnings.
Stock-Based Compensation	Stock-Based Compensation Stock-based compensation expense is measured at the grant-date fair value of the award and recognized as compensation expense over the vesting period.
Income Taxes	Income Taxes The Company uses the asset and liability method to account for income taxes. Accordingly, deferred income taxes are recognized for differences between the financial statement and tax bases of assets and liabilities at enacted statutory tax rates in effect for the years in which differences are expected to reverse. Changes in tax rates are recognized directly to the income statement as they arise. Consideration is given to positive and negative evidence related to the realization of the deferred tax assets and valuation allowances are established to reduce deferred tax assets to the amounts expected to be realized. Significant judgment is required in making this assessment. For uncertain tax positions, the Company recognizes tax benefits that are more likely than not to be sustained upon examination by tax authorities. The amount recognized is measured as the largest amount of benefit that is greater than 50 percent likely to be realized. With regard to non-US subsidiaries, the Company will indefinitely reinvest any future earnings outside of the U.S. and currently does not have any undistributed earnings.
Concentrations	Concentrations One customer represented slightly less than 10% of the total consolidated revenues of the Company for the year ended December 31, 2015. This customer accounted for more than 10% of the total consolidated revenues of the Company for the two years ended December 31, 2014 and 2013 . All customer amounts disclosed in the table are related to biomass-based diesel sales: 2015 2014 2013 Customer A $ 114,030 $ 231,780 $ 243,258 The Company maintains cash balances at financial institutions, which may at times exceed the $250 coverage by the U.S. Federal Deposit Insurance Company.
Use of Estimates	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, disclosure of contingent assets and liabilities at the dates of the financial statements and reported amounts of revenues and expenses during the reporting periods. These estimates are based on information that is currently available to management and on various assumptions that the Company believes to be reasonable under the circumstances. Actual results could differ from those estimates.
New Accounting Pronouncements	New Accounting Pronouncements In April 2015, the FASB issued ASU 2015-03 S implifying the Presentation of Debt Issuance Costs . The amendments in this update require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The guidance in the ASU is effective for financial statements issued for fiscal years beginning after December 15, 2015 and interim periods within fiscal years beginning after December 15, 2016. The Company has evaluated the impact of this guidance on its consolidated financial statements and elected to early adopt the guidance in the year ended December 31, 2015. Early adoption of the guidance did not have any material impact on the Company's consolidated financial statements for the year ended December 31, 2015. Certain amounts on the consolidated financial statements have been reclassified to conform to the current year's presentation as a result of early adopting the guidance. In July 2015, the FASB issued ASU 2015-11, S implifying the Measurement of Inventory , which requires entities to measure most inventory “at the lower of cost and net realizable value,” thereby simplifying the current guidance under which an entity must measure inventory at the lower of cost or market. The guidance is effective prospectively for annual periods beginning after December 15, 2016, and interim periods therein. The Company has evaluated the impact of this guidance on its consolidated financial statements and elected to early adopt the guidance in the year ended December 31, 2015 given the level and nature of its inventory turnover. Early adoption of the guidance did not have any material impact on the Company's consolidated financial statements for the year ended December 31, 2015. In July 2015, the FASB decided to defer by one year the effective dates of the new revenue recognition standard as provided by the ASU 2014-09, Revenue from Contracts with Customers: Summary and Amendments that Create Revenue from Contracts with Customers and Other Assets and Deferred Costs—Contracts with Customers . Early adoption is permitted for all entities, but not before the original public entity effective date. For public companies, the update will now be effective for interim and annual periods beginning after December 15, 2017. The Company is currently evaluating the impact that this guidance will have on its consolidated financial statements. In September 2015, the FASB issued ASU 2015-16, Business Combinations (Topic 805): Simplifying the Accounting Measurement-Period Adjustments that eliminates the requirement that an acquirer in a business combination account for measurement-period adjustments retrospectively. Instead, a measurement-period adjustment will be recognized in the period in which it determines the amount of the adjustment. The guidance is effective for public business entities for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. The Company is currently evaluating the impact this guidance will have on its consolidated financial statements. In November 2015, the FASB issued ASU 2015-17, Income Taxes, Balance Sheet Classification of Deferred Taxes , requiring entities to classify all deferred tax assets and liabilities as noncurrent on the balance sheet instead of separating deferred taxes into current and noncurrent accounts. All valuation allowances are required to be classified as noncurrent. The guidance is effective for financial statements issued for annual periods beginning after December 15, 2016, and interim periods within those annual periods. The Company has evaluated the impact of this guidance on its consolidated financial statements and elected to early adopt the guidance for the year ended December 31, 2015. In January 2016, the FASB issued ASU 2016-01, Financial instruments - Overall - Recognition and Measurement of Financial Assets and Financial Liabilities , which requires entities to measure equity investments that do not result in consolidation and are not accounted for under the equity method at fair value and recognize any changes in fair value in net income unless the investment qualify for the new practicability exception. The guidance is effective for calendar-year public entities beginning in 2018. The Company is still evaluating the impact of this guidance, but does not expect it to have any material impact on its consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, Leases , that requires lessees to put most leases on their balance sheets but recognize expenses on their income statements in a manner similar to today’s accounting. The guidance also eliminates today’s real estate-specific provisions for all entities. For lessors, the guidance modifies the classification criteria and the accounting for sales-type and direct financing leases. The guidance is effective for calendar-year public entities beginning in 2019. The Company is still evaluating the impact of this guidance on its consolidated financial statements.

Summary of Significant Accoun35

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Activity regarding the allowance for doubtful accounts	Activity regarding the allowance for doubtful accounts was as follows: Balance, January 1, 2013 $ 1,972 Amount charged to selling, general and administrative expenses 309 Charge-offs, net of recoveries (157 ) Balance, December 31, 2013 2,124 Amount charged to selling, general and administrative expenses 1,453 Charge-offs, net of recoveries (1,304 ) Balance, December 31, 2014 2,273 Amount charged to selling, general and administrative expenses (803 ) Charge-offs, net of recoveries (119 ) Balance, December 31, 2015 $ 1,351
Estimated useful lives	Depreciation expense is computed on a straight-line method based upon estimated useful lives of the assets. Estimated useful lives are as follows: Automobiles and trucks 5 years Computers and office equipment 5 years Office furniture and fixtures 7 years Machinery and equipment 5-30 years Leasehold improvements the lesser of the lease term or 30 years Buildings and improvements 30-40 years
Goodwill for Company's business segments	The following table summarizes goodwill for the Company’s reportable segments: Biomass-based Diesel Services Renewable Chemicals Total Beginning balance - January 1, 2014 $ 68,784 $ 16,080 $ — $ 84,864 Acquisitions 68,564 — 34,847 103,411 Ending balance - December 31, 2014 137,348 16,080 34,847 188,275 Finalization of purchase accounting 2,833 — — 2,833 Impairment charge $ (140,181 ) $ — $ (34,847 ) (175,028 ) Ending balance - December 31, 2015 $ — $ 16,080 $ — $ 16,080
Concentration risk by customer	One customer represented slightly less than 10% of the total consolidated revenues of the Company for the year ended December 31, 2015. This customer accounted for more than 10% of the total consolidated revenues of the Company for the two years ended December 31, 2014 and 2013 . All customer amounts disclosed in the table are related to biomass-based diesel sales: 2015 2014 2013 Customer A $ 114,030 $ 231,780 $ 243,258

Acquisitions (Tables)

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2015
Imperium Renewables, Inc.
Business Acquisition [Line Items]
Schedule of Business Acquisitions	The following table summarizes the estimated fair values of the assets acquired and liabilities assumed at the acquisition date. August 19, 2015 Assets (liabilities) acquired of Imperium: Cash $ 168 Accounts receivable 8,274 Inventory 18,989 Other current assets 87 Property, plant and equipment 46,476 Intangible assets 2,900 Total identifiable assets acquired 76,894 Accounts payable (4,828 ) Accrued expenses and other liabilities (942 ) Debt (5,225 ) Deferred tax liabilities (3,483 ) Total liabilities assumed (14,478 ) Net identifiable assets acquired 62,416 Less: Bargain purchase gain 5,358 Net assets acquired $ 57,058 The following table summarizes the consideration paid for Imperium: August 19, 2015 Consideration at fair value for Imperium: Cash $ 36,748 Common stock 15,310 Contingent consideration 5,000 Total $ 57,058
Acquisition, Pro Forma	The following pro forma condensed combined results of operations assume that the Imperium acquisition was completed as of January 1, 2013 and as if the stock had been issued on the same date. Year ended December 31, 2015 Year ended December 31, 2014 Year ended December 31, 2013 Revenues $ 1,505,513 $ 1,453,331 $ 1,556,798 Net income (loss) attributable to the Company's common stockholders (155,870 ) 94,129 172,314 Basic net income (loss) per share attributable to common stockholders $(3.46) $2.22 $4.96
LS9, Inc
Business Acquisition [Line Items]
Schedule of Business Acquisitions	This acquisition's finalized purchase price allocation did not result in material adjustments. The following table summarizes the consideration paid and the amounts of assets acquired and liabilities assumed at the acquisition date: January 22, 2014 Consideration at fair value: Cash $ 15,275 Common stock 26,254 Contingent consideration 17,050 Total $ 58,579
Syntroleum Corporation
Business Acquisition [Line Items]
Schedule of Business Acquisitions	The following table summarizes the consideration paid for Syntroleum. June 3, 2014 Consideration at fair value for Syntroleum: Common stock $ 34,831
Dynamic Fuels, LLC
Business Acquisition [Line Items]
Schedule of Business Acquisitions	The following table summarizes the consideration paid to Tyson Foods for Dynamic Fuels: June 6, 2014 Consideration at fair value for Dynamic Fuels: Cash $ 16,447 Contingent consideration 28,900 Total $ 45,347
Syntroleum Corporation and Dynamic Fuels, LLC
Business Acquisition [Line Items]
Schedule of Business Acquisitions	The following table summarizes the amount of assets acquired and liabilities assumed at the acquisition date for the combined acquisition of Syntroleum and Dynamic Fuels: June 6, 2014 Assets (liabilities) acquired of Syntroleum and Dynamic Fuels: Cash $ 253 Other current assets 4,666 Property, plant and equipment 121,567 Goodwill 71,398 Intangible assets 8,900 Other noncurrent assets 10,281 Other current liabilities (1,024 ) Deferred tax liabilities (8,310 ) Debt (113,553 ) Other noncurrent liabilities (14,000 ) Total $ 80,178
Petrotec AG
Business Acquisition [Line Items]
Schedule of Business Acquisitions	The following table summarizes the fair values of the assets acquired and liabilities assumed at the acquisition date as the purchase price allocation was finalized: December 24, 2014 Assets (liabilities) acquired of Petrotec: Cash $ 13,523 Accounts receivable 4,989 Inventory 9,470 Other current assets 3,583 Property, plant and equipment 25,026 Other noncurrent assets 369 Total identifiable assets acquired 56,960 Accounts payable (8,171 ) Accrued expenses and other liabilities (2,151 ) Debt (16,192 ) Non-current liabilities (1,462 ) Total liabilities assumed (27,976 ) Net identifiable assets acquired 28,984 Non-controlling interest (8,962 ) Net assets acquired $ 20,022 The following table summarizes the consideration paid for Petrotec: December 24, 2014 Consideration at fair value for Petrotec: Common stock $ 20,022

Marketable Securities (Tables)

Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2015
Investments, Debt and Equity Securities [Abstract]
Marketable Securities	The Company's investments in marketable securities are stated at fair value and are available-for-sale. The Company has no outstanding marketable securities as of December 31, 2015 . The following table summarizes the Company's marketable securities at December 31, 2014: As of December 31, 2014 Maturity Gross Amortized Cost Total Unrealized Gains Total Unrealized Losses Fair Value Corporate bonds Within one year $ 6,781 $ — $ (6 ) $ 6,775 Certificates of deposit Within one year 10,000 — (5 ) 9,995 Total $ 16,781 $ — $ (11 ) $ 16,770

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2015
Inventory Disclosure [Abstract]
Inventories	Inventories consist of the following at December 31: 2015 2014 Raw materials $ 28,989 $ 23,117 Work in process 3,014 2,879 Finished goods 53,887 71,512 Total $ 85,890 $ 97,508

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Property, plant and equipment	Company's owned property, plant and equipment consists of the following at December 31: 2015 2014 Land $ 4,221 $ 3,437 Building and improvements 103,199 96,298 Leasehold improvements 8,149 10,023 Machinery and equipment 397,632 355,332 513,201 465,090 Accumulated depreciation (75,119 ) (53,889 ) 438,082 411,201 Construction in process 136,502 81,995 Total $ 574,584 $ 493,196

Intangible Assets (Tables)

Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Components of Intangible assets	Amortizing intangible assets consist of the following at December 31: December 31, 2015 Cost Accumulated Amortization Net Weighted Average Remaining Life Raw material supply agreement $ 6,230 $ (1,551 ) $ 4,679 10.0 years Renewable hydrocarbon diesel technology 8,300 (876 ) 7,424 13.5 years Acquired customer relationships 2,900 (106 ) 2,794 9.6 years Ground lease 200 (112 ) 88 5.9 years Total amortizing intangibles 17,630 (2,645 ) 14,985 In-process research and development, indefinite lives 15,956 — 15,956 Total intangible assets $ 33,586 $ (2,645 ) $ 30,941 December 31, 2014 Cost Accumulated Amortization Net Weighted Average Remaining Life Raw material supply agreement $ 5,914 $ (1,113 ) $ 4,801 11.0 years Renewable hydrocarbon diesel technology 8,300 (323 ) 7,977 14.5 years Ground lease 200 (97 ) 103 6.9 years Total amortizing intangibles 14,414 (1,533 ) 12,881 In-process research and development, indefinite lives 15,956 — 15,956 Total intangible assets $ 30,370 $ (1,533 ) $ 28,837
Estimated amortization expense	Estimated amortization expense for fiscal years ended December 31 is as follows: 2016 $ 1,329 2017 1,343 2018 1,357 2019 1,372 2020 1,388 Thereafter 8,196 Total $ 14,985

Other Assets (Tables)

Other Assets (Tables)	12 Months Ended
	Dec. 31, 2015
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Summary of prepaid expense and other current assets	Prepaid expenses and other current assets consist of the following at December 31: 2015 2014 Commodity derivatives and related collateral, net $ 10,097 $ 12,938 Prepaid expenses 8,504 7,901 Deposits 3,824 4,481 RIN inventory 5,656 10,795 Taxes receivable 1,814 2,843 Other 1,987 4,177 Total $ 31,882 $ 43,135
Summary of other noncurrent assets	Other noncurrent assets consist of the following at December 31: 2015 2014 Spare parts inventory $ 2,922 $ 3,440 Deposits 2,370 4,370 Other 6,527 6,624 Total $ 11,819 $ 14,434

Accrued Expenses and Other Li42

Accrued Expenses and Other Liabilities (Tables)	12 Months Ended
	Dec. 31, 2015
Accrued Liabilities [Abstract]
Summary of accrued expenses and other liabilities	Accrued expenses and other liabilities consist of the following at December 31: 2015 2014 Accrued property taxes $ 1,056 $ 1,412 Accrued employee compensation 8,776 10,639 Accrued interest 578 683 Deferred grant revenue — 745 Contingent consideration, current portion 14,762 9,228 Unfavorable lease obligation, current portion 1,828 1,828 Other 1,466 3,951 Total $ 28,466 $ 28,486
Summary of other noncurrent liabilities	Other noncurrent liabilities consist of the following at December 31: 2015 2014 Straight-line lease liability $ 2,751 $ 3,111 Asset retirement obligations 1,062 990 Other 1,097 1,465 Total $ 4,910 $ 5,566

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Company's borrowings	The Company’s term debt at December 31 is as follows: 2015 2014 2.75% Convertible debt, $143,750 face amount, due in June 2019 $ 126,053 $ 121,354 REG Geismar GOZone bonds, secured, variable interest rate, due in October 2033 100,000 100,000 REG Danville term loan, secured, variable interest rate of LIBOR plus 5%, due in November 2015 — 1,513 REG Newton term loan, secured, variable interest rate of LIBOR plus 4%, due in December 2018 16,800 19,868 REG Mason City term loan, fixed interest rate of 5%, due in July 2019 3,675 4,566 REG Ames term loans, secured, fixed interest rates of 3.5% and 4.25%, due in January 2018 and December 2019, respectively 3,901 4,226 REG Grays Harbor term loan, variable interest of minimum 3.5% or Prime Rate plus 0.25%, due in May 2022 5,225 — Other 908 1,402 Total debt before debt issuance costs 256,562 252,929 Less: Current portion of long-term debt 5,206 5,746 Less: Debt issuance costs (net of accumulated amortization of $ 2,296 and $1,474, respectively) 4,105 5,152 Total long-term debt $ 247,251 $ 242,031
Summary of company's revolving borrowings	The Company’s revolving debt at December 31 are as follows: 2015 2014 Total revolving loans (current) $ 23,149 $ 16,679 Maximum remaining available to be borrowed under revolving line of credit $ 23,067 $ 20,719
Summary of maturities of the term borrowings	Maturities of the term debt, including the convertible debt, are as follows for the years ending December 31: 2016 $ 5,206 2017 5,248 2018 15,718 2019 128,091 2020 929 Thereafter 101,370 Total 256,562 Less: current portion 5,206 $ 251,356

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income tax benefit (expense)	Income tax benefit (expense) for the years ended December 31 is as follows: 2015 2014 2013 Current income tax benefit (expense) Federal $ — $ — $ 2,432 State — — 2,492 Foreign (225 ) — — (225 ) — 4,924 Deferred income tax benefit (expense) Federal 24,151 (14,112 ) 15,297 State 9,736 1,420 3,736 Foreign 1,035 9 — Net operating loss carryforwards created 88,110 61,640 48,024 123,032 48,957 67,057 Income tax benefit (expense) before valuation allowances 122,807 48,957 71,981 Deferred tax valuation allowances (114,106 ) (52,529 ) (76,916 ) Income tax benefit (expense) $ 8,701 $ (3,572 ) $ (4,935 )
Effective income tax rate continuing operations tax rate reconciliation	A reconciliation of the reported amount of income tax expense to the amount computed by applying the statutory federal income tax rate to earnings from continuing operations before income taxes is as follows: 2015 2014 2013 U.S. Federal income tax expense at a statutory rate of 35 percent $ 56,144 $ (30,139 ) $ (66,955 ) State taxes, net of federal income tax benefit 12,777 5,119 6,905 Tax position on government incentives 85,423 76,662 131,829 Goodwill impairment (35,062 ) — — Bargain purchase gain 1,875 — — Other 1,650 (2,685 ) 202 Total (expense) benefits for income taxes before valuation allowances 122,807 48,957 71,981 Valuation allowances (114,106 ) (52,529 ) (76,916 ) Total benefit (expense) for income taxes $ 8,701 $ (3,572 ) $ (4,935 )
Tax effects of temporary differences that give rise to the Company's deferred tax assets and liabilities	The tax effects of temporary differences that give rise to the Company’s deferred tax assets and liabilities at December 31 are as follows: 2015 2014 Current Noncurrent Current Noncurrent Deferred Tax Assets: Goodwill $ — $ 39,172 $ — $ 13,716 Net operating loss carryforwards — 243,865 — 154,020 Tax credit carryforwards — 1,597 — 1,597 Start-up costs — 988 — 1,111 Stock-based compensation — 4,703 — 3,469 Terminal leases — 3,859 — 4,229 Capitalized research and development — 8,096 — 3,711 Accrued compensation — 2,546 3,422 — Inventory capitalization — 2,046 1,600 — Allowance for doubtful accounts — 567 931 — Other — 1,569 56 1,474 Deferred tax assets — 309,008 6,009 183,327 Deferred Tax Liabilities: Prepaid expenses — (1,338 ) (1,239 ) — Property, plant and equipment — (65,398 ) — (53,133 ) Intangibles — (3,909 ) — (3,018 ) Deferred revenue — — (4,443 ) — Convertible debt — (3,626 ) (4,599 ) — Unrealized gain (loss) on available for sale investments — (1,752 ) (5,767 ) — Other — (2,007 ) (527 ) (1,867 ) Deferred tax liabilities — (78,030 ) (16,575 ) (58,018 ) Net deferred tax assets (liabilities) — 230,978 (10,566 ) 125,309 Valuation allowance — (250,164 ) (4,333 ) (132,214 ) Net deferred taxes $ — $ (19,186 ) $ (14,899 ) $ (6,905 )
Valuation allowance for deferred tax assets	Activity regarding the valuation allowance for deferred tax assets was as follows: 2015 2014 2013 Beginning of year balance $ 136,547 $ 76,916 $ — Changes in valuation allowance charged to income 114,106 52,529 76,916 Foreign currency translation (773 ) — — Acquisition 284 7,102 — End of year balance $ 250,164 $ 136,547 $ 76,916
Reconciliation of total amounts of unrecognized tax benefits	A reconciliation of the total amounts of unrecognized tax benefits at December 31 is as follows: 2015 2014 2013 Beginning and end of year balance $ 1,900 $ 1,900 $ 1,900

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary about the Company's Common Stock restricted stock units granted, vested, exercised and forfeited	The following table summarizes information about the Company’s Common Stock RSU’s granted, vested, exercised and forfeited: Number of Awards Weighted Average Issue Price Awards outstanding - January 1, 2013 505,616 $17.14 Issued 204,183 $11.96 Vested and restriction lapsed (192,190 ) $15.72 Forfeited (16,681 ) $9.98 Awards outstanding - December 31, 2013 500,928 $15.81 Issued 257,030 $10.97 Vested and restriction lapsed (124,906 ) $10.42 Forfeited (16,658 ) $10.95 Awards outstanding - December 31, 2014 616,394 $15.00 Issued 339,280 $9.34 Vested and restriction lapsed (295,089 ) $9.36 Forfeited (22,687 ) $10.56 Awards outstanding - December 31, 2015 637,898 $12.87
Summary about the stock appreciate rights granted, forfeited, vested and exercisable	The following table summarizes information about SAR’s granted, forfeited, vested and exercisable: Number of SAR’s Weighted Average Exercise Price Weighted Average Contractual Term SAR's outstanding - January 1, 2013 1,053,845 $9.47 Granted 335,057 $12.85 Exercised (5,106 ) $8.92 Forfeited (10,727 ) $10.85 SAR's outstanding - December 31, 2013 1,373,069 $10.28 8.6 years Granted 449,225 $11.73 Exercised (435 ) $7.37 Forfeited (12,557 ) $11.57 SAR's outstanding - December 31, 2014 1,809,302 $10.63 8.1 years Granted 655,855 $9.47 Exercised (14,470 ) $9.21 Forfeited (54,561 ) $10.30 SAR's outstanding - December 31, 2015 2,396,126 $10.33 7.6 years SAR's exercisable - December 31, 2015 758,952 $13.69 7.6 years SAR's expected to vest - December 31, 2015 1,479,586 $10.40 7.6 years
Assumptions for Black-Scholes options pricing model/Estimated fair value of SAR grant using Black-Scholes options pricing model	The fair value of each SAR grant is estimated using the Black-Scholes option-pricing model as set forth in the table below: 2015 2014 2013 The weighted average fair value of stock appreciation rights issued (per unit) $3.33 - $3.90 $4.18 - $4.93 $2.54 - $6.51 Dividend yield —% —% —% Weighted average risk-free interest rate 1.4% - 1.6% 1.5% - 1.8% 0.7% - 1.8% Weighted average expected volatility 40% 40% 40% Expected life in years 6.25 6.25 6.25
Common Stock options granted, exercised, forfeited, vested and exercisable	The following table summarizes information about Common Stock options granted, exercised, forfeited, vested and exercisable: Number of Options Weighted Average Exercise Price Weighted Average Contractual Term Options outstanding - January 1, 2013 87,026 $23.75 3.6 years Granted — $— Exercised — $— Forfeited — $— Options outstanding - December 31, 2013 87,026 $23.75 2.6 years Granted — $— Exercised — $— Forfeited — $— Options outstanding - December 31, 2014 87,026 $23.75 1.6 years Granted — $— Exercised — $— Forfeited — $— Options outstanding - December 31, 2015 87,026 $23.75 0.6 years Options exercisable - December 31, 2015 87,026 $23.75 0.6 years

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2015
Related Party Transactions [Abstract]
Summary of Related Party Transactions	The Company will report related party transactions before and after the IPO based on the related party characteristics mentioned above. Summary of Related Party Transactions - Consolidated Statements of Operations 2015 2014 2013 Cost of goods sold - Biomass-based diesel (a) $ 4,542 $ 42,622 $ 49,358 Selling, general and administrative expenses (a) $ — $ 45 $ 37 Interest expense (a) $ — $ 7 $ 30 (a) Represents transactions with West Central prior to the Company's determination that West Central was no longer a related party. Summary of Related Party Balances - Consolidated Balance Sheets 2015 2014 Accounts receivable (a) $ — $ 36 Accounts payable (a) $ — $ 1,101

Operating Leases (Tables)

Operating Leases (Tables)	12 Months Ended
	Dec. 31, 2015
Leases, Operating [Abstract]
Future minimum lease payments under operating leases	For each of the next five calendar years and thereafter, future minimum lease payments under operating leases that have initial or remaining noncancelable lease terms in excess of one year are as follows: Total Payments 2016 $ 18,339 2017 14,164 2018 13,515 2019 12,219 2020 10,749 Thereafter 50,449 Total minimum payments $ 119,435

Derivative Instruments (Tables)

Derivative Instruments (Tables)	12 Months Ended
	Dec. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Summary of Derivative Financial Instruments by Balance Sheet Location	The following tables provide details regarding the Company’s derivative financial instruments: December 31, 2015 December 31, 2014 Assets Liabilities Assets Liabilities Gross amounts of commodity derivative contracts recognized at fair value $ 4,644 $ 185 $ 14,901 $ 205 Cash collateral 5,638 — 2,870 4,628 Total gross amount recognized 10,282 185 17,771 4,833 Gross amounts offset (185 ) (185 ) (4,833 ) (4,833 ) Net amount reported in the Consolidated Balance Sheets $ 10,097 $ — $ 12,938 $ —
Summary of Derivative Financial Instruments by Location of Gain (Loss)	The following table sets forth the pre-tax gains (losses) included in the Consolidated Statements of Operations: Location of Gain (Loss) 2015 2014 2013 Commodity derivatives Cost of goods sold – Biomass-based diesel $ 35,983 $ 61,631 $ (5,656 )

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Assets (liabilities) measured at fair value	A summary of assets (liabilities) measured at fair value is as follows: As of December 31, 2015 Total Level 1 Level 2 Level 3 Commodity contract derivatives $ 4,459 $ 2,196 $ 2,263 $ — Contingent consideration for LS9 acquisition $ (7,590 ) — — (7,590 ) Contingent consideration for Dynamic Fuels acquisition $ (29,209 ) — — (29,209 ) Contingent consideration for Imperium acquisition $ (4,913 ) — — (4,913 ) $ (37,253 ) $ 2,196 $ 2,263 $ (41,712 ) As of December 31, 2014 Total Level 1 Level 2 Level 3 Money market funds $ 302 $ 302 $ — $ — Certificates of deposit $ 9,995 — 9,995 — Commercial notes/bonds $ 6,775 — 6,775 — Commodity contract derivatives $ 14,696 6,885 7,811 — Contingent consideration for LS9 acquisition $ (8,624 ) — — (8,624 ) Contingent consideration for Dynamic Fuels acquisition $ (30,695 ) — — (30,695 ) $ (7,551 ) $ 7,187 $ 24,581 $ (39,319 )
Liabilities measured at fair value on a recurring basis	The following is a reconciliation of the beginning and ending balances for liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) during the years ended as follows: Contingent Consideration for LS9 Acquisition Contingent Consideration for Dynamic Fuels Acquisition Contingent Consideration for Imperium Acquisition Balance at January 1, 2013 and December 31, 2013 $ — $ — $ — Issuance of contingent consideration for acquisitions 17,050 28,900 — Change in estimates included in earnings (8,426 ) 1,795 — Settlements — — — Balance at December 31, 2014 8,624 30,695 — Issuance of contingent consideration for acquisitions — — 5,000 Change in estimates included in earnings (1,034 ) 675 — Settlements — (2,161 ) (87 ) Ending balance - December 31, 2015 $ 7,590 $ 29,209 $ 4,913
Estimated fair values of the Company's financial instruments	The estimated fair values of the Company’s financial instruments, which are not recorded at fair value are as follows as of December 31: 2015 2014 Asset (Liability) Carrying Amount Estimated Fair Value Asset (Liability) Carrying Amount Estimated Fair Value Financial Liabilities: Debt and lines of credit $ (279,711 ) $ (275,123 ) $ (269,608 ) $ (270,331 )

Net Income (Loss) Per Share (Ta

Net Income (Loss) Per Share (Tables)	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Dilutive weighted average securities were excluded from the calculation of diluted net income (loss) per share attributable to common stockholders during the periods	The following potentially dilutive weighted average securities were excluded from the calculation of diluted net income per share attributable to common stockholders during the periods presented as the effect was anti-dilutive: Year Ended December 31, 2015 2014 2013 Options to purchase common stock 87,026 87,026 87,026 Stock appreciation rights 2,072,130 1,400,824 1,030,926 Warrants to purchase common stock — 17,916 — Convertible notes 10,838,218 6,295,075 — Total 12,997,374 7,800,841 1,117,952
Calculation of diluted net income per share	The following table presents the calculation of diluted net income per share for the years ended December 31, 2015 , 2014 and 2013 (in thousands, except share and per share data): 2015 2014 2013 Net income (loss) attributable to the Company's common stockholders - Basic $ (151,392 ) $ 81,620 $ 165,254 Plus: distributed dividends to Preferred Stockholders — 40 2,055 Plus (less): effect of participating securities — (418 ) (2,051 ) Net income (loss) attributable to the Company's common stockholders - Diluted $ (151,392 ) $ 81,242 $ 165,258 Shares: Weighted-average shares outstanding - Basic 43,958,803 40,740,411 33,045,164 Adjustment to reflect stock appreciation right conversions — 9,502 7,065 Adjustment to reflect warrants to purchase common stock — — 650 Weighted-average shares outstanding - Diluted 43,958,803 40,749,913 33,052,879 Net income (loss) per share attributable to common stockholders - Diluted $ (3.44 ) $ 1.99 $ 5.00

Reportable Segments and Geogr51

Reportable Segments and Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2015
Segment Reporting [Abstract]
Segment for the results of operations	The following table represents the significant items by reportable segment for the results of operations for the years ended December 31, 2015 , 2014 and 2013 : 2015 2014 2013 Net sales: Biomass-based Diesel (includes Petrotec's net sales of $145,039, $3,563 and $0, respectively) $ 1,326,452 $ 1,264,850 $ 1,500,580 Services 102,731 85,149 56,121 Corporate and other 68,984 11,940 — Intersegment revenues (110,823 ) (88,108 ) (58,563 ) $ 1,387,344 $ 1,273,831 $ 1,498,138 Income (loss) before income taxes Biomass-based diesel (includes Petrotec's losses of $(1,643), $(337) and $0, respectively) $ (100,152 ) $ 104,136 $ 201,114 Services 6,323 6,980 3,851 Renewable Chemicals (52,728 ) (12,252 ) — Corporate and other (13,854 ) (12,754 ) (13,664 ) $ (160,411 ) $ 86,110 $ 191,301 Depreciation and amortization expense, net: Biomass-based diesel (includes Petrotec's amounts of $3,259, $0, $0, respectively) $ 22,799 $ 13,497 $ 8,611 Services 302 204 120 Renewable Chemicals 1,413 1,293 — Corporate and other 1,362 802 511 $ 25,876 $ 15,796 $ 9,242 Cash paid for purchases of property, plant and equipment: Biomass-based diesel (includes Petrotec's amounts of $1,816, $0, $0, respectively) $ 59,859 $ 52,846 $ 36,770 Services 1,510 643 504 Renewable Chemicals 672 532 — Corporate and other 2,436 6,142 1,779 $ 64,477 $ 60,163 $ 39,053 2015 2014 Goodwill: Biomass-based diesel $ — $ 137,348 Services 16,080 16,080 Renewable Chemicals — 34,847 $ 16,080 $ 188,275 Assets: Biomass-based diesel (including Petrotec's assets of $45,471 and $56,960) $ 1,048,923 $ 1,150,851 Services 60,308 46,560 Renewable Chemicals 23,872 59,134 Corporate and other 308,782 235,823 Intersegment eliminations $ (218,265 ) $ (124,632 ) $ 1,223,620 $ 1,367,736
Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas	The following geographic data include net sales attributed to the countries based on the location of the subsidiary making the sale and long-lived assets based on physical location. Long-lived assets represent the net book value of property, plant and equipment. Sales and long-lived assets of the Company's investment in Petrotec comprise substantially all of the amounts categorized as Foreign in the table below. 2015 2014 2013 Net sales: United States $ 1,242,305 $ 1,270,268 $ 1,498,138 Foreign 145,039 3,563 — $ 1,387,344 $ 1,273,831 $ 1,498,138 2015 2014 Long-lived assets: United States $ 553,987 $ 468,170 Foreign 20,597 25,026 $ 574,584 $ 493,196

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Contractual Obligation, Fiscal Year Maturity Schedule	The following table outlines the minimum take or pay requirement related to the purchase of hydrogen, nitrogen, utilities and natural gas. 2016 $ 3,857 2017 3,857 2018 3,784 2019 3,748 2020 3,297 Thereafter 12,733 Total $ 31,276

Supplemental Quarterly Inform53

Supplemental Quarterly Information (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Significant items for the results of operations on a quarterly basis	The following table represents the significant items for the results of operations on a quarterly basis for the years ended December 31, 2015 and 2014 : Three Months Three Months Three Months Three Months Revenues $ 230,918 $ 373,762 $ 394,856 $ 387,808 Gross profit (loss) (16,195 ) 15,907 4,405 106,426 Selling, general, and administrative expenses including research and development expense 20,535 19,749 21,995 27,969 Impairment of goodwill — — — 175,028 Loss from operations (36,730 ) (3,842 ) (17,590 ) (96,571 ) Other income (expense), net (2,471 ) 972 869 (5,048 ) Net loss attributable to the Company (38,107 ) (2,001 ) (15,675 ) (95,609 ) Net loss per share attributable to common stockholders - basic (0.86 ) (0.05 ) (0.36 ) (2.18 ) Net loss per share attributable to common stockholders - diluted (0.86 ) (0.05 ) (0.36 ) (2.18 ) Three Months Three Months Three Months Three Months Revenues $ 219,040 $ 332,918 $ 384,258 $ 337,615 Gross profit 11,564 15,151 22,715 111,182 Selling, general, and administrative expenses including research and development expense 13,527 15,627 16,707 29,244 Income (loss) from operations (1,963 ) (476 ) 6,008 81,938 Other income (expense), net (503 ) (436 ) (1,684 ) 3,226 Net income (loss) attributable to the Company (2,359 ) 11,007 4,572 69,391 Net income (loss) per share attributable to common stockholders - basic (0.05 ) 0.27 0.11 1.61 Net income (loss) per share attributable to common stockholders - diluted (0.06 ) 0.27 0.11 1.61

Organization, Presentation, a54

Organization, Presentation, and Nature of the Business - (Details) gal in Millions	12 Months Ended
	Dec. 31, 2015facilitybiorefinerygal
Class of Stock [Line Items]
Number of operating biodiesel production facilities	10
Production capacity per year | gal	432
Number of fermentation facilities	1
Number of multi-feedstock capable plants	7
Number of non-operating biodiesel production facilities	1
Petrotec AG
Class of Stock [Line Items]
Number of biorefineries | biorefinery	2
Construction in Progress
Class of Stock [Line Items]
Number of operating biodiesel production facilities	3

Summary of Significant Accoun55

Summary of Significant Accounting Policies - (Details Textual)	1 Months Ended		3 Months Ended							9 Months Ended	12 Months Ended
	Sep. 30, 2015USD ($)	Apr. 30, 2015USD ($)	Dec. 31, 2015USD ($)	Oct. 31, 2015$ / shares	Sep. 30, 2015USD ($)	Jul. 31, 2015$ / shares	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2015USD ($)renewable_identification_numbercustomer	Dec. 31, 2014USD ($)customer	Dec. 31, 2013USD ($)customer	Nov. 04, 2015$ / shares	Feb. 28, 2015USD ($)	Jun. 30, 2014USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash, FDIC Insured Amount			$ 250							$ 250	$ 250
Current restricted cash			0						$ 12,845,000	0	0	$ 12,845,000
Non-current restricted cash			105,815,000						104,815,000	105,815,000	105,815,000	104,815,000
Estimated impaired fixed assets	$ 1,414,000	$ 11,027,000								12,441,000
Insurance recoveries										11,027,000
Proceeds from business interruption insurance										4,293,000
Capitalization of interest incurred on debt during construction			897,000						1,345,000	897,000	897,000	1,345,000	$ 335,000
Stock price (in dollars per share) | $ / shares														$ 7.06
Average closing stock price (in dollars per share) | $ / shares				$ 8.57		$ 10.84
Impairment of goodwill			175,028,000		$ 0		$ 0	$ 0			175,028,000	0	0
Asset impairment charges											0	0	0
Amortization Of Long Term Capital Lease Obligations											1,828,000
Convertible senior notes																$ 143,750,000
Stock repurchase program, amount authorized to be repurchased															$ 30,000,000
Stock repurchase program, amount repurchased											23,313,000
Revenues											624,000	600,000	2,813,000
Biomass-based diesel government incentives											245,868,000	220,634,000	290,393,000
Advertising Costs											$ 1,288,000	755,000	648,000
Matching contributions											50.00%
Participants eligible earnings											6.00%
Total expense related to the Company's defined contribution plan											$ 1,071,000	855,000	$ 533,000
Biomass-based Diesel
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum percentage increase in fair value of each of the reporting units over its carrying value through annual impairment test											5.00%
Impairment of goodwill											$ 140,181,000
Biomass-based diesel government incentives			95,008,000						78,781		$ 95,008,000	78,781
Services
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum percentage increase in fair value of each of the reporting units over its carrying value through annual impairment test											21.00%
Impairment of goodwill											$ 0
Renewable Chemicals
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum percentage increase in fair value of each of the reporting units over its carrying value through annual impairment test											12.00%
Impairment of goodwill											$ 34,847,000
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RINs per gallon | renewable_identification_number											1.5
Allowed RINs per gallon | renewable_identification_number											0
Stock price (in dollars per share) | $ / shares				7.25
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RINs per gallon | renewable_identification_number											1.7
Allowed RINs per gallon | renewable_identification_number											2.5
Stock price (in dollars per share) | $ / shares				$ 11.18
Dynamic Fuels, LLC
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-current restricted cash			101,315,000							101,315,000	$ 101,315,000
REG Energy Services
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-current restricted cash			$ 4,500,000						$ 3,500,000	$ 4,500,000	4,500,000	$ 3,500,000
Other Operating Income (Expense)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Asset impairment charges											$ 1,915,000
Customer A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of customers | customer											1	1,000	1,000

Summary of Significant Accoun56

Summary of Significant Accounting Policies - Accounts Receivable (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Activity regarding the allowance for doubtful accounts
Balance	$ 2,273	$ 2,124	$ 1,972
Amount charged to selling, general and administrative expenses	(803)	1,453	309
Charge-offs, net of recoveries	(119)	(1,304)	(157)
Balance	$ 1,351	$ 2,273	$ 2,124

Summary of Significant Accoun57

Summary of Significant Accounting Policies - Property, Plant and Equipment (Details)	12 Months Ended
	Dec. 31, 2015
Automobiles and trucks
Estimated useful lives
Estimated useful lives	5 years
Computers and office equipment
Estimated useful lives
Estimated useful lives	5 years
Office furniture and fixtures
Estimated useful lives
Estimated useful lives	7 years
Machinery and equipment | Minimum
Estimated useful lives
Estimated useful lives	5 years
Machinery and equipment | Maximum
Estimated useful lives
Estimated useful lives	30 years
Leasehold improvements
Estimated useful lives
Estimated useful lives	30 years
Buildings and improvements | Minimum
Estimated useful lives
Estimated useful lives	30 years
Buildings and improvements | Maximum
Estimated useful lives
Estimated useful lives	40 years

Summary of Significant Accoun58

Summary of Significant Accounting Policies - Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Goodwill for Company's business segments
Beginning Balance -				$ 188,275	$ 188,275	$ 84,864
Acquisitions						103,411
Finalization of purchase accounting					2,833
Goodwill, Impairment Loss	$ (175,028)	$ 0	$ 0	0	(175,028)	0	$ 0
Ending Balance -	16,080				16,080	188,275	84,864
Biomass-based Diesel
Goodwill for Company's business segments
Beginning Balance -				137,348	137,348	68,784
Acquisitions						68,564
Finalization of purchase accounting					2,833
Goodwill, Impairment Loss					(140,181)
Ending Balance -	0				0	137,348	68,784
Services
Goodwill for Company's business segments
Beginning Balance -				16,080	16,080	16,080
Acquisitions						0
Finalization of purchase accounting					0
Goodwill, Impairment Loss					0
Ending Balance -	16,080				16,080	16,080	16,080
Renewable Chemicals
Goodwill for Company's business segments
Beginning Balance -				$ 34,847	34,847	0
Acquisitions						34,847
Finalization of purchase accounting					0
Goodwill, Impairment Loss					(34,847)
Ending Balance -	$ 0				$ 0	$ 34,847	$ 0

Summary of Significant Accoun59

Summary of Significant Accounting Policies - Concentrations (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Concentration Risk [Line Items]
Revenues	$ 387,808	$ 394,856	$ 373,762	$ 230,918	$ 337,615	$ 384,258	$ 332,918	$ 219,040	$ 1,387,344	$ 1,273,831	$ 1,498,138
Customer A
Concentration Risk [Line Items]
Revenues									$ 114,030	$ 231,780	$ 243,258

Stockholders' Equity of the C60

Stockholders' Equity of the Company - (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Common stock, shares authorized (in shares)	300,000,000	300,000,000
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Exercise price per share (in dollars per share)	$ 11.16
Direct stock issuance costs	$ 0	$ 1,587	$ 114
Capital Stock
Common stock, shares authorized (in shares)	450,000,000
Common Stock | Initial public offering
Common stock, shares authorized (in shares)	300,000,000
Class A Common Stock
Common stock, shares authorized (in shares)	140,000,000
Preferred Stock
Preferred stock (in shares)	10,000,000
Series B Preferred Stock
Preferred stock (in shares)	3,000,000
Blackhawk warrant holders
Warrants issued (in shares)	0	0
Warrants outstanding (in shares)	0

Redeemable Preferred Stock - (D

Redeemable Preferred Stock - (Details) - $ / shares	3 Months Ended
	Sep. 30, 2013	Dec. 31, 2015	Nov. 04, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Share price (in dollars per share)			$ 7.06
Common Stock
Class of Stock [Line Items]
Share price (in dollars per share)	$ 15
Minimum trading days	20 days
Consecutive trading days	30 days
Average daily trading volume (in shares)	200,000
Percentage of outstanding shares of preferred stock series	50.00%
Convertible Preferred Stock, Shares Issued upon Conversion (in shares)	1,047,465
Series B Preferred Stock
Class of Stock [Line Items]
Conversion of Stock, Shares Converted (in shares)	518,365
Shares outstanding (in shares)		0		0

Acquisitions - (Details)

Acquisitions - (Details) - USD ($) $ in Thousands	Aug. 19, 2015	Jun. 06, 2014	Jan. 22, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 24, 2014	Jun. 03, 2014
Business Acquisition [Line Items]
Cash				$ 41,409	$ 19,369	$ 10,933
Summary of allocations of the purchase price to the fair values of the assets acquired and liabilities assumed at the date of acquisition
Goodwill				16,080	188,275	84,864
Debt				(5,225)	(129,745)
Bargain purchase gain				5,358	0	$ 0
Contingent consideration				26,949	30,091
Imperium Renewables, Inc.
Business Acquisition [Line Items]
Cash	$ 36,748
Common stock	15,310
Contingent consideration	5,000
Total	57,058
Summary of allocations of the purchase price to the fair values of the assets acquired and liabilities assumed at the date of acquisition
Cash	168
Accounts receivable	8,274
Inventory	18,989
Other current assets	87
Property, plant and equipment	46,476
In-process research & development intangible assets	2,900
Total identifiable assets acquired	76,894
Accounts payable	(4,828)
Other current liabilities	(942)
Debt	(5,225)
Deferred tax liabilities	(3,483)
Total liabilities assumed	(14,478)
Total	62,416
Bargain purchase gain	5,358
Net assets acquired	$ 57,058
Contingent consideration				4,913
Petrotec AG
Summary of allocations of the purchase price to the fair values of the assets acquired and liabilities assumed at the date of acquisition
Cash							$ 13,523
Accounts receivable							4,989
Inventory							9,470
Other current assets							3,583
Property, plant and equipment							25,026
In-process research & development intangible assets							369
Total identifiable assets acquired							56,960
Accounts payable							(8,171)
Other current liabilities							(2,151)
Debt							(16,192)
Other noncurrent liabilities							(1,462)
Total liabilities assumed							(27,976)
Total							28,984
Non-controlling interest							(8,962)
Net assets acquired							20,022
Common stock							$ 20,022
Syntroleum Corporation
Summary of allocations of the purchase price to the fair values of the assets acquired and liabilities assumed at the date of acquisition
Common stock								$ 34,831
Contingent consideration				29,209
Dynamic Fuels, LLC
Business Acquisition [Line Items]
Cash		$ 16,447
Total		45,347
Summary of allocations of the purchase price to the fair values of the assets acquired and liabilities assumed at the date of acquisition
Contingent consideration		28,900
Syntroleum Corporation and Dynamic Fuels, LLC
Summary of allocations of the purchase price to the fair values of the assets acquired and liabilities assumed at the date of acquisition
Cash		253
Other current assets		4,666
Goodwill		71,398
Property, plant and equipment		121,567
In-process research & development intangible assets		8,900
Other noncurrent assets		10,281
Other current liabilities		(1,024)
Debt		(113,553)
Other noncurrent liabilities		(14,000)
Deferred tax liabilities		(8,310)
Net assets acquired		$ 80,178
LS9, Inc
Business Acquisition [Line Items]
Cash			$ 15,275
Total			58,579
Summary of allocations of the purchase price to the fair values of the assets acquired and liabilities assumed at the date of acquisition
Goodwill			34,846
Property, plant and equipment			8,215
In-process research & development intangible assets			15,956
Other noncurrent liabilities			(438)
Net assets acquired			58,579
Common stock			26,254
Contingent consideration			$ 17,050	$ 7,590	$ 8,624

Acquisitions - (Details Textual

Acquisitions - (Details Textual) $ in Thousands, gal in Millions	Dec. 31, 2015USD ($)gal	Aug. 19, 2015USD ($)sharesgal	Dec. 24, 2014USD ($)shares	Jul. 25, 2014USD ($)	Jun. 06, 2014USD ($)	Jun. 03, 2014USD ($)sharesgal	Jan. 22, 2014USD ($)shares	Jul. 30, 2013USD ($)gal	Dec. 31, 2015USD ($)gal	Dec. 31, 2015USD ($)gal	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	Jul. 24, 2014
Business Acquisition [Line Items]
Production capacity per year | gal	432								432	432
Contingent consideration	$ 26,949								$ 26,949	$ 26,949	$ 30,091
Contingent consideration, current portion	14,762								14,762	14,762	9,228
Bargain purchase gain										5,358	0	$ 0
Goodwill	16,080								16,080	16,080	188,275	84,864
Cash										41,409	19,369	10,933
Debt assumed in acquisition	5,225								5,225	5,225	129,745
Issuance of note payable for acquisition												$ 5,135
Tyson Foods
Business Acquisition [Line Items]
Contingent consideration					$ 35,000
Imperium Renewables, Inc.
Business Acquisition [Line Items]
Production capacity per year | gal		100
Class A Common Stock (in shares) | shares		1,675,000
Contingent consideration	4,913								4,913	4,913
Earnout payment period		2 years
Contingent consideration, current portion	3,534								3,534	$ 3,534
Bargain purchase gain		$ 5,358
Cash		36,748
Total purchase price		57,058
Cash		168
Other current assets		87
Property, plant and equipment		46,476
In-process research & development intangible assets		2,900
Other current liabilities		942
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent		3,483
Debt assumed in acquisition		$ 5,225
Risk adjusted discount rate										10.00%
LS9, Inc
Business Acquisition [Line Items]
Class A Common Stock (in shares) | shares							2,230,559
Contingent consideration	7,590						$ 17,050		7,590	$ 7,590	8,624
Contingent consideration, current portion	3,958								3,958	$ 3,958	$ 0
Goodwill							34,846
Fair value of consideration transferred							26,254
Cash							15,275
Total purchase price							58,579
Property, plant and equipment							8,215
In-process research & development intangible assets							15,956
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other							438
Risk adjusted discount rate										8.00%
Earnout Payments							$ 21,500
Earnout payment period							5 years
Syntroleum Corporation
Business Acquisition [Line Items]
Class A Common Stock (in shares) | shares						3,493,613
Contingent consideration	29,209								29,209	$ 29,209
Contingent consideration, current portion	$ 7,270								7,270	$ 7,270
Fair value of consideration transferred						$ 34,831
Risk adjusted discount rate					5.80%
Syntroleum Corporation | Dynamic Fuels, LLC
Business Acquisition [Line Items]
Production capacity per year | gal						75
Interest acquired					50.00%	50.00%
Dynamic Fuels, LLC
Business Acquisition [Line Items]
Contingent consideration					$ 28,900
Cash					16,447
Total purchase price					45,347
Increase in goodwill					3,202
Risk adjusted discount rate										5.80%
Syntroleum Corporation and Dynamic Fuels, LLC
Business Acquisition [Line Items]
Goodwill					71,398
Cash					253
Other current assets					4,666
Property, plant and equipment					121,567
In-process research & development intangible assets					8,900
Other noncurrent assets					10,281
Other current liabilities					1,024
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent					8,310
Debt assumed in acquisition					113,553
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other					14,000
Syntroleum Corporation and Dynamic Fuels, LLC | Tyson Foods
Business Acquisition [Line Items]
Repayments of Debt					$ 13,553
416 S. Bell, LLC
Business Acquisition [Line Items]
Cash				$ 1,423
Ownership percentage				50.00%									50.00%
Petrotec AG
Business Acquisition [Line Items]
Class A Common Stock (in shares) | shares			2,070,538
Interest acquired	87.49%		69.08%
Noncontrolling interest percent			30.92%
Fair value of noncontrolling interest			$ 8,962
Acquisition related costs									$ 1,289
Payments to Acquire Additional Interest in Subsidiaries										$ 4,828
Fair value of consideration transferred			20,022
Cash			13,523
Other current assets			3,583
Property, plant and equipment			25,026
In-process research & development intangible assets			369
Other current liabilities			2,151
Debt assumed in acquisition			16,192
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other			$ 1,462
Soy Energy, LLC
Business Acquisition [Line Items]
Production capacity per year | gal								30
Cash								$ 10,933
Property, plant and equipment								16,085
Other current liabilities								17
Issuance of note payable for acquisition								$ 5,135

Acquisitions - Pro Forma (Detai

Acquisitions - Pro Forma (Details) - Imperium Renewables, Inc. - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Revenues	$ 1,505,513	$ 1,453,331	$ 1,556,798
Net income (loss)	$ (155,870)	$ 94,129	$ 172,314
Basic net income (loss) per share (in dollars per share)	$ (3.46)	$ 2.22	$ 4.96

Marketable Securities (Details)

Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Gross Amortized Cost		$ 16,781
Total Unrealized Gains		0
Total Unrealized Losses		(11)
Fair Value	$ 0	16,770
Corporate bonds
Schedule of Available-for-sale Securities [Line Items]
Gross Amortized Cost		6,781
Total Unrealized Gains		0
Total Unrealized Losses		(6)
Fair Value		6,775
Certificates of deposit
Schedule of Available-for-sale Securities [Line Items]
Gross Amortized Cost		10,000
Total Unrealized Gains		0
Total Unrealized Losses		(5)
Fair Value		$ 9,995

Inventories - (Details)

Inventories - (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Inventories
Raw materials	$ 28,989	$ 23,117
Work in process	3,014	2,879
Finished goods	53,887	71,512
Total	$ 85,890	$ 97,508

Property, Plant and Equipment -

Property, Plant and Equipment - (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, plant and equipment
Property, Plant and Equipment	$ 513,201	$ 465,090
Accumulated depreciation	(75,119)	(53,889)
Property plant and equipment net excluding construction in progress	438,082	411,201
Construction in process	136,502	81,995
Total	574,584	493,196
Land
Property, plant and equipment
Property, Plant and Equipment	4,221	3,437
Buildings and improvements
Property, plant and equipment
Property, Plant and Equipment	103,199	96,298
Leasehold improvements
Property, plant and equipment
Property, Plant and Equipment	8,149	10,023
Machinery and equipment
Property, plant and equipment
Property, Plant and Equipment	397,632	$ 355,332
REG Geismar, LLC
Property, plant and equipment
Construction in process	37,258
REG Danville, LLC
Property, plant and equipment
Construction in process	$ 15,986

Intangible Assets - (Details)

Intangible Assets - (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Components of Intangible assets
Cost	$ 17,630	$ 14,414
Accumulated amortization	(2,645)	(1,533)
Net	14,985	12,881
Cost	33,586	30,370
Accumulated Amortization	(2,645)	(1,533)
Net	30,941	28,837
In-process research and development, indefinite lives
Components of Intangible assets
Cost	15,956	15,956
Accumulated Amortization	0	0
Net	15,956	15,956
Raw material supply agreement
Components of Intangible assets
Cost	6,230	5,914
Accumulated amortization	(1,551)	(1,113)
Net	$ 4,679	$ 4,801
Weighted Average Remaining Life	10 years	11 years
Renewable hydrocarbon diesel technology
Components of Intangible assets
Cost	$ 8,300	$ 8,300
Accumulated amortization	(876)	(323)
Net	$ 7,424	$ 7,977
Weighted Average Remaining Life	13 years 6 months	14 years 6 months
Acquired customer relationships
Components of Intangible assets
Cost	$ 2,900
Accumulated amortization	(106)
Net	$ 2,794
Weighted Average Remaining Life	9 years 7 months 15 days
Ground lease
Components of Intangible assets
Cost	$ 200	$ 200
Accumulated amortization	(112)	(97)
Net	$ 88	$ 103
Weighted Average Remaining Life	5 years 10 months 24 days	6 years 10 months 24 days

Intangible Assets - (Details Te

Intangible Assets - (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Indefinite-lived Intangible Assets [Line Items]
Amortization expense	$ 1,112	$ 1,298	$ 325
Raw material supply agreement
Indefinite-lived Intangible Assets [Line Items]
Useful life	15 years

Intangible Assets - Estimated A

Intangible Assets - Estimated Amortization Expense (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Estimated amortization expense
2,016	$ 1,329
2,017	1,343
2,018	1,357
2,019	1,372
2,020	1,388
Thereafter	8,196
Net	$ 14,985	$ 12,881

Other Assets - (Details)

Other Assets - (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Summary of prepaid expense and other current assets
Commodity derivatives and related collateral, net	$ 10,097	$ 12,938
Prepaid Expense, Current	8,504	7,901
Deposits	3,824	4,481
RIN inventory	5,656	10,795
Taxes receivable	1,814	2,843
Other	1,987	4,177
Total	$ 31,882	$ 43,135

Other Assets - (Details Textual

Other Assets - (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
RIN
Inventory [Line Items]
Inventory reduced to lower of cost or market	$ 3,027	$ 1,042

Other Assets - Other Noncurrent

Other Assets - Other Noncurrent Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Summary of other noncurrent assets
Spare parts inventory	$ 2,922	$ 3,440
Deposits	2,370	4,370
Other	6,527	6,624
Total	$ 11,819	$ 14,434

Accrued Expenses and Other Li74

Accrued Expenses and Other Liabilities - (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Summary of accrued expenses and other liabilities
Accrued property taxes	$ 1,056	$ 1,412
Accrued employee compensation	8,776	10,639
Accrued interest	578	683
Deferred grant revenue	0	745
Contingent consideration, current portion	14,762	9,228
Unfavorable lease obligation, current portion	1,828	1,828
Other	1,466	3,951
Total	$ 28,466	$ 28,486

Accrued Expenses and Other Li75

Accrued Expenses and Other Liabilities - Other Noncurrent Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Summary of other noncurrent liabilities
Straight-line lease liability	$ 2,751	$ 3,111
Asset retirement obligations	1,062	990
Other	1,097	1,465
Total	$ 4,910	$ 5,566

Debt - (Details)

Debt - (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Line of Credit Facility [Line Items]
Total debt before debt issuance costs	$ 256,562	$ 252,929
Less: Current portion of long-term debt	5,206	5,746
Less: Debt issuance costs (net of accumulated amortization of $ 2,296 and $1,474, respectively)	4,105	5,152
Total long-term debt	247,251	242,031
Accumulated amortization on debt issuance costs	2,296	1,474
2.75% Convertible debt, $143,750 face amount, due in June 2019
Line of Credit Facility [Line Items]
Total debt before debt issuance costs	126,053	121,354
REG Geismar GOZone bonds, secured, variable interest rate, due in October 2033
Line of Credit Facility [Line Items]
Total debt before debt issuance costs	100,000	100,000
REG Danville term loan, secured, variable interest rate of LIBOR plus 5%, due in November 2015
Line of Credit Facility [Line Items]
Total debt before debt issuance costs	0	1,513
REG Newton term loan, secured, variable interest rate of LIBOR plus 4%, due in December 2018
Line of Credit Facility [Line Items]
Total debt before debt issuance costs	16,800	19,868
REG Mason City term loan, fixed interest rate of 5%, due in July 2019
Line of Credit Facility [Line Items]
Total debt before debt issuance costs	$ 3,675	$ 4,566
Interest rate	5.00%	5.00%
REG Ames term loans, secured, fixed interest rates of 3.5% and 4.25%, due in January 2018 and December 2019, respectively
Line of Credit Facility [Line Items]
Total debt before debt issuance costs	$ 3,901	$ 4,226
REG Grays Harbor term loan, variable interest of minimum 3.5% or Prime Rate plus 0.25%, due in May 2022
Line of Credit Facility [Line Items]
Total debt before debt issuance costs	5,225	0
Other
Line of Credit Facility [Line Items]
Total debt before debt issuance costs	$ 908	$ 1,402

Debt - (Details Textual)

Debt - (Details Textual)	Jul. 08, 2014USD ($)	Jun. 30, 2014USD ($)$ / shares$ / Warrant	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Short-term Debt [Line Items]
Cash received on convertible debt			$ 0	$ 143,750,000	$ 0
Available borrowing capacity			46,216,000
Revolving line of credit			23,149,000	16,679,000
Maximum remaining available to be borrowed under revolving line of credit			$ 23,067,000	$ 20,719,000
REG Mason City term loan, fixed interest rate of 5%, due in July 2019
Short-term Debt [Line Items]
Interest rate			5.00%	5.00%
Wells Fargo Revolver
Short-term Debt [Line Items]
Additional increase in maximum borrowing capacity			$ 60,000,000
Fixed Charge Coverage Ratio			100.00%
Excess Availability			$ 6,000,000
Line Of Credit Facility Limitation Amount			$ 25,000,000
Wells Fargo Revolver | Maximum
Short-term Debt [Line Items]
LIBOR Rate Margin			4.25%
Wells Fargo Revolver | Minimum
Short-term Debt [Line Items]
LIBOR Rate Margin			2.50%
REG Ames term loans, secured, fixed interest rates of 3.5% and 4.25%, due in January 2018 and December 2019, respectively | Maximum
Short-term Debt [Line Items]
Interest rate			4.25%	4.25%
REG Ames term loans, secured, fixed interest rates of 3.5% and 4.25%, due in January 2018 and December 2019, respectively | Minimum
Short-term Debt [Line Items]
Interest rate			3.50%	3.50%
REG Grays Harbor | Minimum
Short-term Debt [Line Items]
Interest rate			3.50%	3.50%
REG Danville, LLC
Short-term Debt [Line Items]
Interest to be accrued			LIBOR plus 5% per annum	LIBOR plus 5% per annum
Reg Newton
Short-term Debt [Line Items]
Interest to be accrued			LIBOR plus 4% per annum	LIBOR plus 4% per annum
REG Grays Harbor
Short-term Debt [Line Items]
Interest to be accrued			Minimum 3.% or Prime Rate plus 0.25%	Minimum 3.% or Prime Rate plus 0.25%
Gulf Opportunity Zone Bonds
Short-term Debt [Line Items]
Value of notes issued	$ 100,000,000
Letter of credit	101,315,000
Interest	1,315,000
Amount owed	$ 101,315,000
2.75% Convertible debt, $143,750 face amount, due in June 2019
Short-term Debt [Line Items]
Value of notes issued		$ 143,750,000	$ 143,750,000	$ 143,750,000
Conversion rate		75.3963
Initial conversion price (in dollars per share) | $ / shares		$ 13.26
Effective interest rate		3.80%
Cash received on convertible debt		$ 143,750,000
Percentage of shares covered by capped call		92.50%
Cap price | $ / Warrant		16.02
Value of purchased capped calls		$ 11,904,000
Interest rate			2.75%	2.75%
Debt Instrument, Redemption, Period One | 2.75% Convertible debt, $143,750 face amount, due in June 2019
Short-term Debt [Line Items]
Threshold Percentage of Stock Price Trigger		130.00%
Debt Instrument, Redemption, Period Two | 2.75% Convertible debt, $143,750 face amount, due in June 2019
Short-term Debt [Line Items]
Threshold Percentage of Stock Price Trigger		98.00%
Long-term Debt | 2.75% Convertible debt, $143,750 face amount, due in June 2019
Short-term Debt [Line Items]
Cash received on convertible debt		$ 118,719,000
Stockholders' Equity, Total | 2.75% Convertible debt, $143,750 face amount, due in June 2019
Short-term Debt [Line Items]
Cash received on convertible debt		25,031,000
Deferred Financing and Equity Costs | 2.75% Convertible debt, $143,750 face amount, due in June 2019
Short-term Debt [Line Items]
Cash received on convertible debt		$ 4,563,000
LIBOR | REG Danville, LLC
Short-term Debt [Line Items]
Variable interest rate			5.00%	5.00%
LIBOR | Reg Newton
Short-term Debt [Line Items]
Variable interest rate			4.00%	4.00%
Prime Rate | REG Grays Harbor
Short-term Debt [Line Items]
Variable interest rate			0.25%	0.25%

Debt - Revolving Borrowings (De

Debt - Revolving Borrowings (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Summary of company's revolving borrowings
Total revolving loans (current)	$ 23,149	$ 16,679
Maximum remaining available to be borrowed under revolving line of credit	$ 23,067	$ 20,719

Debt - Maturities of Borrowings

Debt - Maturities of Borrowings (Details) $ in Thousands	Dec. 31, 2015USD ($)
Summary of maturities of the term borrowings
2,016	$ 5,206
2,017	5,248
2,018	15,718
2,019	128,091
2,020	929
Thereafter	101,370
Total	256,562
Less: current portion	5,206
Noncurrent	$ 251,356

Income Taxes - Income Tax Benef

Income Taxes - Income Tax Benefit (Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current income tax benefit (expense)
Federal	$ 0	$ 0	$ 2,432
State	0	0	2,492
Foreign	(225)	0	0
Current income tax (expense) benefit	(225)	0	4,924
Deferred income tax benefit (expense)
Federal	24,151	(14,112)	15,297
State	9,736	1,420	3,736
Foreign	1,035	9	0
Net operating loss carryforwards created	88,110	61,640	48,024
Deferred income tax (expense) benefit	123,032	48,957	67,057
Income tax benefit (expense) before valuation allowances	122,807	48,957	71,981
Deferred tax valuation allowances	(114,106)	(52,529)	(76,916)
Income tax benefit (expense)	$ 8,701	$ (3,572)	$ (4,935)

Income Taxes - Effective Income

Income Taxes - Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Statutory rate	35.00%	35.00%	35.00%
Effective income tax rate continuing operations tax rate reconciliation
U.S. Federal income tax expense at a statutory rate of 35 percent	$ 56,144	$ (30,139)	$ (66,955)
State taxes, net of federal income tax benefit	12,777	5,119	6,905
Tax position on government incentives	85,423	76,662	131,829
Goodwill impairment	(35,062)	0	0
Bargain purchase gain	1,875	0	0
Other	1,650	(2,685)	202
Total (expense) benefits for income taxes before valuation allowances	122,807	48,957	71,981
Valuation allowances	(114,106)	(52,529)	(76,916)
Income tax expense	$ (8,701)	$ 3,572	$ 4,935

Income Taxes - Deferred Tax Ass

Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred Tax Assets:
Goodwill, Noncurrent	$ 39,172	$ 13,716
Net operating loss carryforwards, Noncurrent	243,865	154,020
Tax credit carryforwards, Noncurrent	1,597	1,597
Start-up costs, Noncurrent	988	1,111
Stock-based compensation, Noncurrent	4,703	3,469
Terminal leases	3,859	4,229
Capitalized research and development, Noncurrent	8,096	3,711
Accrued compensation, Current	2,546	3,422
Inventory capitalization, Current	2,046	1,600
Allowance for doubtful accounts, Current	567	931
Other, Current		56
Other, Noncurrent	1,569	1,474
Deferred tax assets Current		6,009
Deferred tax assets Noncurrent	309,008	183,327
Deferred Tax Liabilities:
Prepaid expenses	(1,338)	(1,239)
Property, plant and equipment, Noncurrent	(65,398)	(53,133)
Intangibles, Noncurrent	(3,909)	(3,018)
Deferred revenue	0	(4,443)
Convertible debt	(3,626)	(4,599)
Unrealized gain (loss) on available for sale investments, current	(1,752)	(5,767)
Other, current		(527)
Other, Noncurrent	(2,007)	(1,867)
Deferred tax liabilities, Current		(16,575)
Deferred tax liabilities, Noncurrent	(78,030)	(58,018)
Net deferred tax (liabilities), Current		10,566
Net deferred tax assets, Noncurrent	230,978	125,309
Valuation Allowance, Current		(4,333)
Valuation Allowance, Noncurrent	(250,164)	(132,214)
Net deferred tax, Current		(14,899)
Net deferred tax, Noncurrent	$ (19,186)	$ (6,905)

Income Taxes - (Details Textual

Income Taxes - (Details Textual) - USD ($)	3 Months Ended				12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Item Effected [Line Items]
Impairment of goodwill	$ 175,028,000	$ 0	$ 0	$ 0	$ 175,028,000	$ 0	$ 0
Impairment of goodwill, not tax deductible					100,177,000
Tax impact related to the non-deductible portion of the goodwill impairment change					35,062,000
Net deferred tax, Current						(14,899,000)
Net deferred tax, Noncurrent	(19,186,000)				(19,186,000)	(6,905,000)
Deferred tax asset reflecting federal and state net operating losses	243,865,000				243,865,000	154,020,000
Federal net operating losses	617,698,000				$ 617,698,000
Expiration date for federal net operating losses					2,028
Unrecognized tax benefits that would affect the effective tax rate	$ 0				$ 0	0	$ 1,428,000
Period for unrecognized tax benefits to increase or decrease					12 months
Interest and penalties related to unrecognized tax benefits					$ 0
Accounting Standards Update 2015-17 [Member]
Item Effected [Line Items]
Net deferred tax, Current						0
Net deferred tax, Noncurrent						$ (21,804,000)

Income Taxes - Valuation Allowa

Income Taxes - Valuation Allowance for Deferred Tax Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning of year balance	$ 136,547	$ 76,916	$ 0
Changes in valuation allowance charged to income	114,106	52,529	76,916
Foreign currency translation	(773)	0	0
Acquisition	284	7,102	0
End of year balance	$ 250,164	$ 136,547	$ 76,916

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning of year balance	$ 1,900	$ 1,900	$ 1,900

Stock-Based Compensation - (Det

Stock-Based Compensation - (Details Textual) - USD ($) $ in Thousands	May. 15, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Oct. 26, 2011
Stock-Based Compensation (Textual) [Abstract]
Common Stock (in shares)	5,960,000				4,160,000
Number of additional shares reserved for issuance (in shares)	1,800,000
Stock-based compensation cost relating to the stock options and restricted stock units		$ 5,161	$ 5,883	$ 5,416
Unrecognized compensation expense		$ 6,438
Expected period of unrecognized compensation expense		3 years 2 months 9 days
Restricted stock units
Stock-Based Compensation (Textual) [Abstract]
Conversion of common stock upon vesting (in shares)		1
Service period for RSU awards		3 years
Amount of Awards, Exercised/Restricted stock units vested (in shares)		295,089	124,906	192,190
Restricted stock units | Board of Directors
Stock-Based Compensation (Textual) [Abstract]
Service period for RSU awards		1 year
Restricted stock units | Certain executive management
Stock-Based Compensation (Textual) [Abstract]
Service period for RSU awards		4 years
Stock appreciation rights
Stock-Based Compensation (Textual) [Abstract]
Percentage of SAR's vesting annually		25.00%
Grant expiration period		10 years

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Units (Details) - Restricted Stock Units - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Number of Awards
Awards outstanding, beginning balance (in shares)	616,394	500,928	505,616
Issued (in shares)	339,280	257,030	204,183
Vested and restriction lapsed (in shares)	(295,089)	(124,906)	(192,190)
Forfeited (in shares)	(22,687)	(16,658)	(16,681)
Awards outstanding, ending balance (in shares)	637,898	616,394	500,928
Weighted Average Issue Price (in dollars per share)
Awards outstanding - (in dollars per share)	$ 15	$ 15.81	$ 17.14
Issued (in dollars per share)	9.34	10.97	11.96
Vested and restriction lapsed (in dollars per share)	9.36	10.42	15.72
Forfeited (in dollars per share)	10.56	10.95	9.98
Awards outstanding - (in dollars per share)	$ 12.87	$ 15	$ 15.81

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Appreciation Rights (Details) - Stock Appreciation Rights - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Number of SAR’s
Awards outstanding, beginning balance (in shares)	1,809,302	1,373,069	1,053,845
Granted (in shares)	655,855	449,225	335,057
Exercised (in shares)	(14,470)	(435)	(5,106)
Forfeited (in shares)	(54,561)	(12,557)	(10,727)
Awards outstanding, ending balance (in shares)	2,396,126	1,809,302	1,373,069
Number of SAR's - SAR's exercisable	758,952
Number of SAR's - SAR's expected to vest	1,479,586
Weighted Average Exercise Price (in dollars per share)
SAR's outstanding - (in dollars per share)	$ 10.63	$ 10.28	$ 9.47
Granted (in dollars per share)	9.47	11.73	12.85
Exercised (in dollars per share)	9.21	7.37	8.92
Forfeited (in dollars per share)	10.30	11.57	10.85
SAR's outstanding - (in dollars per share)	10.33	$ 10.63	$ 10.28
Weighted Average Exercise Price - SAR's exercisable (in dollars per share)	13.69
Weighted Average Exercise Price - SAR's expected to vest (in dollars per share)	$ 10.40
Weighted Average Contractual Term - SAR's outstanding	7 years 7 months 6 days	8 years 1 month 6 days	8 years 7 months 6 days
Weighted Average Contractual Term - SAR's expected to vest	7 years 7 months 6 days

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value of SAR's Using Black-Scholes Option-Pricing Model (Details) - Black Scholes - Stock appreciation rights - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Estimated fair value of SAR grant using Black-Scholes options pricing model
Dividend yield	0.00%	0.00%	0.00%
Weighted average risk-free interest rate, Minimum	1.40%	1.50%	0.70%
Weighted average risk-free interest rate, Maximum	1.60%	1.80%	1.80%
Weighted average expected volatility	40.00%	40.00%	40.00%
Expected life in years	6 years 3 months	6 years 3 months	6 years 3 months
Minimum
Estimated fair value of SAR grant using Black-Scholes options pricing model
The weighted average fair value of stock appreciation rights issued (per unit)	$ 3.33	$ 4.18	$ 2.54
Maximum
Estimated fair value of SAR grant using Black-Scholes options pricing model
The weighted average fair value of stock appreciation rights issued (per unit)	$ 3.90	$ 4.93	$ 6.51

Stock-Based Compensation - St90

Stock-Based Compensation - Stock Options (Details) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Number of Options
Options outstanding - (in shares)	87,026	87,026	87,026
Granted (in shares)	0	0	0
Exercised (in shares)	0	0	0
Forfeited (in shares)	0	0	0
Options outstanding - (in shares)	87,026	87,026	87,026	87,026
Number of Options - Options exercisable (in shares)	87,026
Weighted Average Exercise Price (in dollars per share)
Options outstanding - (in dollars per share)	$ 23.75	$ 23.75	$ 23.75
Granted (in dollars per share)	0	0	0
Exercised (in dollars per share)	0	0	0
Forfeited (in dollars per share)	0	0	0
Options outstanding - (in dollars per share)	23.75	$ 23.75	$ 23.75	$ 23.75
Weighted Average Exercise Price - Options exercisable (in dollars per share)	$ 23.75
Weighted Average Contractual Term - Options outstanding	7 months 6 days	1 year 7 months 6 days	2 years 7 months 6 days	3 years 7 months 6 days
Weighted Average Contractual Term - Options exercisable	7 months 6 days

Related Party Transactions - Su

Related Party Transactions - Summary of Related Party Transactions - Consolidated Statements of Operations (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Summary of Related Party Transactions
Cost of goods sold - Biodiesel	[1]	$ 4,542	$ 42,622	$ 49,358
Selling, general, and administrative expenses	[1]	0	45	37
Interest expense	[1]	$ 0	$ 7	$ 30
[1]	Represents transactions with West Central prior to the Company's determination that West Central was no longer a related party.

Related Party Transactions - 92

Related Party Transactions - Summary of Related Party Balances - Consolidated Balance Sheets (Details) - USD ($) $ in Thousands		Dec. 31, 2015	Dec. 31, 2014
Summary of Related Party Balances
Accounts receivable		$ 0	$ 36
Accounts payable		0	1,101
West Central
Summary of Related Party Balances
Accounts receivable	[1]	0	36
Accounts payable	[1]	$ 0	$ 1,101
[1]	Represents balances with West Central.

Related Party Transactions - (D

Related Party Transactions - (Details Textual)	12 Months Ended
	Dec. 31, 2015USD ($)
Lease Agreements
Related Party Transaction [Line Items]
Agreement initial term	20 years
Additional renewal period	30 years
West Central
Related Party Transaction [Line Items]
Annual land lease cost	$ 1

Operating Leases - (Details Tex

Operating Leases - (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Leases, Operating [Abstract]
Total rent expense under operating leases	$ 19,814	$ 17,498	$ 12,549

Operating Leases - (Details)

Operating Leases - (Details) $ in Thousands	Dec. 31, 2015USD ($)
Future minimum lease payments under operating leases
2,016	$ 18,339
2,017	14,164
2,018	13,515
2,019	12,219
2,020	10,749
Thereafter	50,449
Total minimum payments	$ 119,435

Derivative Instruments - (Detai

Derivative Instruments - (Details Textual) lb in Millions, gal in Millions	12 Months Ended
	Dec. 31, 2015USD ($)lbgal
Derivative Instruments, Gain (Loss) [Line Items]
Heating oil covered under the open commodity derivative contracts (in gallons) | gal	47.8
Soybean oil covered under the open commodity derivative contracts (in pounds) | lb	40.1
Net position	$ 10,097,000
Commodity contract derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Collateral associated with commodity-based derivatives	$ 5,638,000

Derivative Instruments - (Det97

Derivative Instruments - (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Assets
Gross amounts of commodity derivative contracts recognized at fair value	$ 4,644	$ 14,901
Cash collateral	5,638	2,870
Total gross amount recognized	10,282	17,771
Gross amounts offset	(185)	(4,833)
Net amount reported in the Consolidated Balance Sheets	10,097	12,938
Liabilities
Gross amounts of commodity derivative contracts recognized at fair value	185	205
Cash collateral	0	4,628
Total gross amount recognized	185	4,833
Gross amounts offset	(185)	(4,833)
Net amount reported in the Consolidated Balance Sheets	$ 0	$ 0

Derivative Instruments - Gains

Derivative Instruments - Gains (Losses) included in the Statements of Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cost of goods sold – Biomass-based diesel | Commodity derivatives
Derivative Instruments, Gain (Loss) [Line Items]
Pre-tax gains (losses) included in the condensed consolidated statement of operations	$ 35,983	$ 61,631	$ (5,656)

Fair Value Measurement - (Detai

Fair Value Measurement - (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	$ (37,253)	$ (7,551)
Level 1
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	2,196	7,187
Level 2
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	2,263	24,581
Level 3
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	(41,712)	(39,319)
Money market funds
Assets (liabilities) measured at fair value
Assets (liabilities), fair value		302
Money market funds | Level 1
Assets (liabilities) measured at fair value
Assets (liabilities), fair value		302
Money market funds | Level 2
Assets (liabilities) measured at fair value
Assets (liabilities), fair value		0
Money market funds | Level 3
Assets (liabilities) measured at fair value
Assets (liabilities), fair value		0
Certificates of deposit
Assets (liabilities) measured at fair value
Assets (liabilities), fair value		9,995
Certificates of deposit | Level 1
Assets (liabilities) measured at fair value
Assets (liabilities), fair value		0
Certificates of deposit | Level 2
Assets (liabilities) measured at fair value
Assets (liabilities), fair value		9,995
Certificates of deposit | Level 3
Assets (liabilities) measured at fair value
Assets (liabilities), fair value		0
Commercial notes/bonds
Assets (liabilities) measured at fair value
Assets (liabilities), fair value		6,775
Commercial notes/bonds | Level 1
Assets (liabilities) measured at fair value
Assets (liabilities), fair value		0
Commercial notes/bonds | Level 2
Assets (liabilities) measured at fair value
Assets (liabilities), fair value		6,775
Commercial notes/bonds | Level 3
Assets (liabilities) measured at fair value
Assets (liabilities), fair value		0
Commodity contract derivatives
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	4,459	14,696
Commodity contract derivatives | Level 1
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	2,196	6,885
Commodity contract derivatives | Level 2
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	2,263	7,811
Commodity contract derivatives | Level 3
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	0	0
Contingent Consideration for Acquisition | LS9, Inc
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	(7,590)	(8,624)
Contingent Consideration for Acquisition | Dynamic Fuels, LLC
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	(29,209)	(30,695)
Contingent Consideration for Acquisition | Imperium Renewables, Inc.
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	(4,913)
Contingent Consideration for Acquisition | Level 1 | LS9, Inc
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	0	0
Contingent Consideration for Acquisition | Level 1 | Dynamic Fuels, LLC
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	0	0
Contingent Consideration for Acquisition | Level 1 | Imperium Renewables, Inc.
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	0
Contingent Consideration for Acquisition | Level 2 | LS9, Inc
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	0	0
Contingent Consideration for Acquisition | Level 2 | Dynamic Fuels, LLC
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	0	0
Contingent Consideration for Acquisition | Level 2 | Imperium Renewables, Inc.
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	0
Contingent Consideration for Acquisition | Level 3 | LS9, Inc
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	(7,590)	(8,624)
Contingent Consideration for Acquisition | Level 3 | Dynamic Fuels, LLC
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	(29,209)	$ (30,695)
Contingent Consideration for Acquisition | Level 3 | Imperium Renewables, Inc.
Assets (liabilities) measured at fair value
Assets (liabilities), fair value	$ (4,913)

Fair Value Measurement - Recurr

Fair Value Measurement - Recurring Basis (Details) - Contingent Consideration for Acquisition - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
LS9, Inc
Liabilities measured at fair value on a recurring basis
Balance at	$ 8,624	$ 0
Issuance of contingent consideration for acquisitions	0	17,050
Change in estimates included in earnings	(1,034)	(8,426)
Settlements	0	0
Balance at	7,590	8,624
Dynamic Fuels, LLC
Liabilities measured at fair value on a recurring basis
Balance at	30,695	0
Issuance of contingent consideration for acquisitions	0	28,900
Change in estimates included in earnings	675	1,795
Settlements	(2,161)	0
Balance at	29,209	30,695
Imperium Renewables, Inc.
Liabilities measured at fair value on a recurring basis
Balance at	0	0
Issuance of contingent consideration for acquisitions	5,000	0
Change in estimates included in earnings	0	0
Settlements	(87)	0
Balance at	$ 4,913	$ 0

Fair Value Measurement - (De101

Fair Value Measurement - (Details Textual) (Details)	12 Months Ended
	Dec. 31, 2015
LS9, Inc
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Risk adjusted discount rate	8.00%
Dynamic Fuels, LLC
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Risk adjusted discount rate	5.80%
Imperium Renewables, Inc.
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Risk adjusted discount rate	10.00%

Fair Value Measurement - Estima

Fair Value Measurement - Estimated Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Asset (Liability) Carrying Amount
Financial Liabilities:
Debt and lines of credit	$ (279,711)	$ (269,608)
Estimated Fair Value
Financial Liabilities:
Debt and lines of credit	$ (275,123)	$ (270,331)

Net Income (Loss) Per Share (De

Net Income (Loss) Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	12,997,374	7,800,841	1,117,952
Convertible notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	10,838,218	6,295,075	0
Stock appreciation rights
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	2,072,130	1,400,824	1,030,926
Options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	87,026	87,026	87,026
Warrants to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	0	17,916	0

Net Income (Loss) Per Share - E

Net Income (Loss) Per Share - EPS Reconciliation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Net income (loss) attributable to the Company's common stockholders - Basic									$ (151,392)	$ 81,620	$ 165,254
Plus: distributed dividends to Preferred Stockholders									0	40	2,055
Plus (less): effect of participating securities									0	(418)	(2,051)
Net income (loss) attributable to the Company's common stockholders - Diluted									$ (151,392)	$ 81,242	$ 165,258
Weighted-average shares outstanding - Basic (in shares)									43,958,803	40,740,411	33,045,164
Adjustment to reflect stock appreciation right conversions (in shares)									0	9,502	7,065
Adjustment to reflect warrants to purchase common stock (in shares)									0	0	650
Weighted-average shares outstanding - Diluted (in shares)									43,958,803	40,749,913	33,052,879
Net income (loss) per share attributable to common stockholders - Diluted (in dollars per share)	$ (2.18)	$ (0.36)	$ (0.05)	$ (0.86)	$ 1.61	$ 0.11	$ 0.27	$ (0.06)	$ (3.44)	$ 1.99	$ 5

Reportable Segments and Geog105

Reportable Segments and Geographic Information - (Details Textual) - segment	3 Months Ended
	Dec. 31, 2015	Sep. 30, 2015
Segment Reporting [Abstract]
Number of Reportable Segments	3	2

Reportable Segments and Geog106

Reportable Segments and Geographic Information - (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment for the results of operations
Net sales:	$ 1,387,344	$ 1,273,831	$ 1,498,138
Income (loss) before income taxes	(160,411)	86,110	191,301
Depreciation and amortization expense, net:	25,876	15,796	9,242
Cash paid for purchases of property, plant and equipment:	64,477	60,163	39,053
Goodwill:	16,080	188,275	84,864
Assets:	1,223,620	1,367,736
Biomass-based Diesel
Segment for the results of operations
Goodwill:	0	137,348	68,784
Services
Segment for the results of operations
Goodwill:	16,080	16,080	16,080
Renewable Chemicals
Segment for the results of operations
Goodwill:	0	34,847	0
Operating Segments | Biomass-based Diesel
Segment for the results of operations
Net sales:	1,326,452	1,264,850	1,500,580
Income (loss) before income taxes	(100,152)	104,136	201,114
Depreciation and amortization expense, net:	22,799	13,497	8,611
Cash paid for purchases of property, plant and equipment:	59,859	52,846	36,770
Goodwill:	0	137,348
Assets:	1,048,923	1,150,851
Operating Segments | Biomass-based Diesel | Petrotec
Segment for the results of operations
Net sales:	145,039	3,563	0
Income (loss) before income taxes	(1,643)	(337)	0
Depreciation and amortization expense, net:	3,259	0	0
Cash paid for purchases of property, plant and equipment:	1,816	0	0
Assets:	45,471	56,960	0
Operating Segments | Services
Segment for the results of operations
Net sales:	102,731	85,149	56,121
Income (loss) before income taxes	6,323	6,980	3,851
Depreciation and amortization expense, net:	302	204	120
Cash paid for purchases of property, plant and equipment:	1,510	643	504
Goodwill:	16,080	16,080
Assets:	60,308	46,560
Operating Segments | Renewable Chemicals
Segment for the results of operations
Income (loss) before income taxes	(52,728)	(12,252)	0
Depreciation and amortization expense, net:	1,413	1,293	0
Cash paid for purchases of property, plant and equipment:	672	532	0
Goodwill:	0	34,847
Assets:	23,872	59,134
Corporate and other
Segment for the results of operations
Income (loss) before income taxes	(13,854)	(12,754)	(13,664)
Depreciation and amortization expense, net:	1,362	802	511
Cash paid for purchases of property, plant and equipment:	2,436	6,142	1,779
Assets:	308,782	235,823
Corporate and other | Services
Segment for the results of operations
Net sales:	68,984	11,940	0
Intersegment revenues
Segment for the results of operations
Net sales:	(110,823)	(88,108)	$ (58,563)
Intersegment eliminations
Segment for the results of operations
Assets:	$ (218,265)	$ (124,632)

Reportable Segments and Geog107

Reportable Segments and Geographic Information - Geographic Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales:	$ 387,808	$ 394,856	$ 373,762	$ 230,918	$ 337,615	$ 384,258	$ 332,918	$ 219,040	$ 1,387,344	$ 1,273,831	$ 1,498,138
Long-lived assets:	574,584				493,196				574,584	493,196
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales:									1,242,305	1,270,268	1,498,138
Long-lived assets:	553,987				468,170				553,987	468,170
Foreign
Revenues from External Customers and Long-Lived Assets [Line Items]
Net sales:									145,039	3,563	$ 0
Long-lived assets:	$ 20,597				$ 25,026				$ 20,597	$ 25,026

Commitments and Contingencie108

Commitments and Contingencies (Details) $ in Thousands	Dec. 31, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,016	$ 3,857
2,017	3,857
2,018	3,784
2,019	3,748
2,020	3,297
Thereafter	12,733
Total	$ 31,276

Supplemental Quarterly Infor109

Supplemental Quarterly Information (Unaudited) - (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Significant items for the results of operations on a quarterly basis
Revenues	$ 387,808,000	$ 394,856,000	$ 373,762,000	$ 230,918,000	$ 337,615,000	$ 384,258,000	$ 332,918,000	$ 219,040,000	$ 1,387,344,000	$ 1,273,831,000	$ 1,498,138,000
Gross profit (loss)	106,426,000	4,405,000	15,907,000	(16,195,000)	111,182,000	22,715,000	15,151,000	11,564,000	110,543,000	160,612,000	239,433,000
Selling, general, and administrative expenses including research and development expense	27,969,000	21,995,000	19,749,000	20,535,000	29,244,000	16,707,000	15,627,000	13,527,000
Impairment of goodwill	175,028,000	0	0	0					175,028,000	0	0
Loss from operations	(96,571,000)	(17,590,000)	(3,842,000)	(36,730,000)	81,938,000	6,008,000	(476,000)	(1,963,000)	(154,733,000)	85,507,000	193,310,000
Other income (expense), net	(5,048,000)	869,000	972,000	(2,471,000)	3,226,000	(1,684,000)	(436,000)	(503,000)	(5,678,000)	603,000	(2,009,000)
Net loss attributable to the Company	$ (95,609,000)	$ (15,675,000)	$ (2,001,000)	$ (38,107,000)	$ 69,391,000	$ 4,572,000	$ 11,007,000	$ (2,359,000)	$ (318,000)	$ (73,000)	$ 0
Net income (loss) per share attributable to common stockholders - basic (in dollars per share)	$ (2.18)	$ (0.36)	$ (0.05)	$ (0.86)	$ 1.61	$ 0.11	$ 0.27	$ (0.05)	$ (3.44)	$ 2	$ 5
Net income (loss) per share attributable to common stockholders - Diluted (in dollars per share)	$ (2.18)	$ (0.36)	$ (0.05)	$ (0.86)	$ 1.61	$ 0.11	$ 0.27	$ (0.06)	$ (3.44)	$ 1.99	$ 5
Biomass-based diesel government incentives									$ 245,868,000	$ 220,634,000	$ 290,393,000
Biomass-based Diesel
Significant items for the results of operations on a quarterly basis
Impairment of goodwill									140,181,000
Biomass-based diesel government incentives	$ 95,008,000				$ 78,781				$ 95,008,000	$ 78,781

Subsequent Events - (Details)

Subsequent Events - (Details) gal in Millions	Feb. 01, 2016USD ($)sharesgal	Dec. 31, 2015USD ($)gal	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)	Mar. 05, 2016USD ($)	Feb. 28, 2015USD ($)
Subsequent Event [Line Items]
Production capacity per year | gal		432
Payment for acquisition		$ 41,409,000	$ 19,369,000	$ 10,933,000
Contingent consideration		$ 26,949,000	$ 30,091,000
Stock repurchase program, amount authorized to be repurchased						$ 30,000,000
Subsequent Event
Subsequent Event [Line Items]
Stock repurchase program, amount authorized to be repurchased					$ 50,000,000
Sanimax | Subsequent Event
Subsequent Event [Line Items]
Production capacity per year | gal	20
Payment for acquisition	$ 11,000,000
Number of shares issued for acquisition | shares	500,000
Contingent consideration	$ 5,000,000
Earnout payment period	7 years