Renewable Energy (REGI) 10-Q 6 Nov 14 2014 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2014	Oct. 31, 2014
Document Document And Entity Information [Abstract]	'	'
Entity Registrant Name	'Renewable Energy Group, Inc.	'
Entity Central Index Key	'0001463258	'
Document Type	'10-Q	'
Document Period End Date	30-Sep-14	'
Amendment Flag	'false	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q3	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	42,306,595

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (Unaudited) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
CURRENT ASSETS:	'	'
Cash and cash equivalents	$67,270	$153,227
Marketable securities	61,378	0
Accounts receivable, net (includes amounts owed by related parties of $141 and $426, respectively)	35,422	82,911
Inventories	49,382	85,814
Prepaid expenses and other assets	39,786	25,568
Total current assets	253,238	347,520
Property, plant and equipment, net	462,053	286,044
Property, plant and equipment, net—variable interest entity	0	5,180
Goodwill	175,472	84,864
Intangible assets, net	29,280	4,867
Deferred income taxes	1,470	0
Other assets (includes amounts owed by related parties of $0 and $35, respectively)	29,356	12,380
Restricted cash	104,815	0
TOTAL ASSETS	1,055,684	740,855
CURRENT LIABILITIES:	'	'
Revolving line of credit	0	10,986
Current maturities of long-term debt	6,105	6,729
Current maturities of long-term debt—variable interest entity	0	300
Accounts payable (includes amounts owed to related parties of $570 and $552, respectively)	53,942	48,727
Accrued expenses and other liabilities	15,361	12,305
Deferred income taxes	8,968	3,687
Deferred revenue	99	15,503
Total current liabilities	84,475	98,237
Unfavorable lease obligation	7,058	7,905
Deferred income taxes	0	2,691
Contingent consideration for acquisitions	39,411	0
Long-term debt	241,495	23,422
Long-term debt—variable interest entity	0	3,729
Other liabilities	4,153	6,838
Total liabilities	376,592	142,822
COMMITMENTS AND CONTINGENCIES (Note 15)	'	'
EQUITY:	'	'
Common stock ($.0001 par value; 300,000,000 shares authorized; 42,306,595 and 36,506,221 shares outstanding, respectively)	4	4
Common stock—additional paid-in-capital	431,300	359,818
Retained earnings	251,692	238,134
Accumulated other comprehensive loss	-18	0
Treasury stock (530,898 and 530,898 shares outstanding, respectively)	-3,886	-3,886
Total stockholders’ equity	679,092	594,070
TOTAL LIABILITIES AND EQUITY	1,055,684	740,855
Series B Preferred Stock	'	'
CURRENT LIABILITIES:	'	'
Series B preferred stock ($.0001 par value; 3,000,000 shares authorized; 0 and 143,313 shares outstanding; redemption amount $0 and $3,583, respectively)	$0	$3,963

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, except Share data, unless otherwise specified
Accounts receivable, amounts owed by related parties	$141	$426
Other assets, amounts owed by related parties	0	35
Accounts payable, amounts owed to related parties	570	552
Common stock, par or stated value per share	$0.00	$0.00
Common stock, shares authorized	300,000,000	300,000,000
Common stock, shares, outstanding	42,306,595	36,506,221
Treasury stock, shares outstanding	530,898	530,898
Series B Preferred Stock	'	'
Preferred stock, par or stated value per share	$0.00	$0.00
Preferred stock, shares authorized	3,000,000	3,000,000
Preferred stock, shares outstanding	0	143,313
Preferred stock, redemption amount	$0	$3,583

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Operations (Unaudited) Statement (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
REVENUES:	'	'	'	'
Biodiesel sales	$382,296	$399,226	$919,255	$859,058
Biodiesel government incentives	1,830	59,203	16,742	248,385
Total biodiesel sales	384,126	458,429	935,997	1,107,443
Services	132	15	219	104
Total revenues	384,258	458,444	936,216	1,107,547
COSTS OF GOODS SOLD:	'	'	'	'
Biodiesel	351,033	388,518	854,800	875,475
Biodiesel—related parties	10,490	12,057	31,919	37,198
Services	20	20	67	149
Total cost of goods sold	361,543	400,595	886,786	912,822
GROSS PROFIT	22,715	57,849	49,430	194,725
SELLING, GENERAL AND ADMINISTRATIVE EXPENSES	16,707	12,686	45,861	33,556
INCOME FROM OPERATIONS	6,008	45,163	3,569	161,169
OTHER INCOME (EXPENSE), NET:	'	'	'	'
Change in fair value of contingent consideration	1,059	0	1,443	0
Other income, net	124	66	556	276
Interest expense	-2,867	-577	-4,622	-1,757
Total other income (expenses)	-1,684	-511	-2,623	-1,481
INCOME BEFORE INCOME TAXES	4,324	44,652	946	159,688
INCOME TAX BENEFIT (EXPENSE)	248	42,051	12,274	-3,452
NET INCOME	4,572	86,703	13,220	156,236
PLUS—GAIN ON REDEMPTION OF PREFERRED STOCK	0	0	378	0
PLUS—CHANGE IN UNDISTRIBUTED DIVIDENDS ALLOCATED TO PREFERRED STOCKHOLDERS	0	-147	0	-147
LESS—DISTRIBUTED DIVIDENDS TO PREFERRED STOCKHOLDERS	0	-258	-40	-1,848
LESS—EFFECT OF PARTICIPATING PREFERRED STOCK	0	-6,455	0	-18,010
LESS—EFFECT OF PARTICIPATING SHARE-BASED AWARDS	-68	-1,381	-196	-2,273
NET INCOME ATTRIBUTABLE TO THE COMPANY’S COMMON STOCKHOLDERS	$4,504	$78,462	$13,362	$133,958
NET INCOME PER SHARE ATTRIBUTABLE TO COMMON STOCKHOLDERS:	'	'	'	'
BASIC	$0.11	$2.32	$0.33	$4.20
DILUTED	$0.11	$2.31	$0.32	$4.20
WEIGHTED AVERAGE SHARES USED TO COMPUTE NET INCOME PER SHARE ATTRIBUTABLE TO COMMON STOCKHOLDERS:	'	'	'	'
BASIC	42,374,768	33,790,034	40,216,467	31,918,951
DILUTED	42,432,005	34,016,476	40,228,929	31,924,197

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) Statement (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]	'	'	'	'
Net income	$4,572	$86,703	$13,220	$156,236
Unrealized gains (losses) on marketable securities, net of taxes of $0 and $0, respectively	4	0	-18	0
Other comprehensive income (loss)	4	0	-18	0
Comprehensive income	$4,576	$86,703	$13,202	$156,236

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) (Parenthetical) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Statement of Comprehensive Income [Abstract]	'	'	'	'
Taxes on unrealized losses on marketable securities	$0	$0	$0	$0

Condensed_Consolidated_Stateme3

Condensed Consolidated Statements of Redeemable Preferred Stock and Equity (Unaudited) (USD $)	Total	Redeemable Preferred Stock	Common Stock	Common Stock - Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock
In Thousands, except Share data, unless otherwise specified
Beginning Balance at Dec. 31, 2012	$324,764	$83,043	$3	$274,136	$53,823	'	($3,198)
Beginning Balance, 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, shares	'	'	58,501	'	'	'	'
Conversion of Series B Preferred Stock to common stock	69,117	-68,479	1	69,116	'	'	'
Conversion of Series B Preferred Stock to common stock, Shares	'	-2,469,489	4,988,995	'	'	'	'
Conversion of restricted stock units to common stock (net of shares of treasury stock purchased)	-158	'	'	'	'	'	-158
Conversion of restricted stock units to common stock (net of shares of treasury stock purchased), Shares	'	'	70,515	'	'	'	'
Stock compensation expense	3,869	'	'	3,869	'	'	'
Net change in unrealized losses on marketable securities	0	'	'	'	'	'	'
Series B Preferred Stock dividends paid	-1,848	'	'	'	-1,848	'	'
Net income	156,236	'	'	'	156,236	'	'
Ending Balance at Sep. 30, 2013	552,403	14,564	4	347,544	208,211	'	-3,356
Ending Balance, Shares at Sep. 30, 2013	'	525,617	35,677,946	'	'	'	'
Beginning Balance at Dec. 31, 2013	594,070	3,963	4	359,818	238,134	'	-3,886
Beginning Balance, 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, shares	'	'	49,662	'	'	'	'
Conversion of Series B Preferred Stock to common stock	23	-23	'	23	'	'	'
Conversion of Series B Preferred Stock to common stock, Shares	'	-816	1,634	'	'	'	'
Preferred stock redemption	378	-3,940	'	'	378	'	'
Preferred stock redemption, shares	'	-142,497	'	'	'	'	'
Issuance of common stock in acquisition (net of issuance costs of $884)	60,196	'	'	60,196	'	'	'
Issuance of common stock in acquisition, shares	'	'	5,724,172	'	'	'	'
Conversion of restricted stock units to common stock (net of shares of treasury stock purchased), Shares	'	'	24,906	'	'	'	'
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	'	'	'
Stock compensation expense	4,041	'	'	4,041	'	'	'
Net change in unrealized losses on marketable securities	-18	'	'	'	'	-18	'
Series B Preferred Stock dividends paid	-40	'	'	'	-40	'	'
Net income	13,220	'	'	'	13,220	'	'
Ending Balance at Sep. 30, 2014	$679,092	'	$4	$431,300	$251,692	($18)	($3,886)
Ending Balance, Shares at Sep. 30, 2014	'	'	42,306,595	'	'	'	'

Condensed_Consolidated_Stateme4

Condensed Consolidated Statements of Redeemable Preferred Stock and Equity (Unaudited) (Parenthetical) (USD $)	9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
Statement of Stockholders' Equity [Abstract]	'	'
Issuance cost of common stock issued in acquisition	$884	'
Conversion of restricted stock units to common stock, shares of treasury stock purchased	'	21,675
Taxes on convertible notes conversion feature	5,082	'
Issuance costs on convertible notes conversion feature	886	'
Taxes on purchase of remaining interest in VIE	$300	'

Condensed_Consolidated_Stateme5

Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013
CASH FLOWS FROM OPERATING ACTIVITIES:	'	'
Net income	$13,220	$156,236
Adjustments to reconcile net income to net cash flows from operating activities:	'	'
Depreciation expense	9,526	6,974
Amortization expense of assets and liabilities, net	412	-365
Accretion of convertible note discount	1,488	0
Change in fair value of contingent consideration	-1,443	0
Gain on disposal of property, plant and equipment	0	-67
Provision for doubtful accounts	356	99
Stock compensation expense	4,041	3,869
Deferred tax expense (benefit)	-12,840	8,872
Other operating activities	437	0
Changes in asset and liabilities, net of effects from acquisitions:	'	'
Accounts receivable, net	47,678	-47,959
Inventories	38,379	-14,681
Prepaid expenses and other assets	-12,358	-24,441
Accounts payable	967	23,843
Accrued expenses and other liabilities	-3,105	3,432
Deferred revenue	-15,404	987
Net cash flows provided by operating activities	71,354	116,799
CASH FLOWS FROM INVESTING ACTIVITIES:	'	'
Cash paid for marketable securities	-80,973	0
Cash receipts from marketable securities	19,174	0
Cash proceeds from involuntary disposal of fixed assets	0	330
Change in restricted cash	-104,815	0
Cash paid for purchase of property, plant and equipment	-45,579	-28,785
Cash paid for acquisitions, net of cash acquired	-32,892	-10,933
Cash paid for investments	-2,779	0
Other investing activities	72	-58
Net cash flows used in investing activities	-247,792	-39,446
CASH FLOWS FROM FINANCING ACTIVITIES:	'	'
Borrowings on line of credit	1,056,596	1,103,568
Repayments on line of credit	-1,067,582	-1,103,568
Cash received from issuance of debt	143,750	3,000
Cash paid for capped call transactions	-11,904	0
Cash paid on debt	-20,340	-9,690
Cash paid for debt issuance costs	-4,381	-47
Cash paid for equity issuance costs	-1,527	-25
Cash paid for treasury stock	-529	-282
Cash paid for preferred stock dividends	-40	-1,205
Cash paid for redemption of preferred stock	-3,562	0
Cash paid for fractional common stock shares	0	-6
Net cash flows provided by (used in) financing activities	90,481	-8,255
NET CHANGE IN CASH AND CASH EQUIVALENTS	-85,957	69,098
CASH AND CASH EQUIVALENTS, Beginning of period	153,227	66,785
CASH AND CASH EQUIVALENTS, End of period	67,270	135,883
SUPPLEMENTAL DISCLOSURES OF CASH FLOWS INFORMATION:	'	'
Cash paid/(received) for income taxes	21	-6,538
Cash paid for interest	2,286	1,496
Amounts included in period-end accounts payable for:	'	'
Purchases of property, plant and equipment	5,905	3,608
Debt issuance cost	60	'
Incentive stock liability for raw material supply agreement	317	439
Equity issuance costs	25	'
Issuance of common stock for acquisitions	61,085	'
Issuance of note payable for acquisition	'	5,135
Contingent consideration for acquisitions	45,950	'
Debt assumed in acquisition	113,553	'
Gain on redemption of preferred stock	378	'
Issuance of common stock for dividends	'	$643

Basis_of_Presentation_and_Natu

Basis of Presentation and Nature of the Business	9 Months Ended
	Sep. 30, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Basis of Presentation and Nature of the Business	'
	BASIS OF PRESENTATION AND NATURE OF THE BUSINESS
	The condensed consolidated financial statements have been prepared by Renewable Energy Group, Inc. and its subsidiaries (the Company), pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (SEC). Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with accounting principles generally accepted in the United States of America (GAAP) have been condensed or omitted as permitted by such rules and regulations. All adjustments, consisting of normal recurring adjustments, have been included. Management believes that the disclosures are adequate to present fairly the financial position, results of operations and cash flows at the dates and for the periods presented. It is suggested that these interim financial statements be read in conjunction with the consolidated financial statements and the notes thereto appearing in the Company’s latest annual report on Form 10-K. Results for interim periods are not necessarily indicative of those to be expected for the fiscal year.
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and related disclosures. Actual results could differ from those estimates.
	As of September 30, 2014, the Company owned biomass-based diesel production facilities with an aggregate nameplate production capacity of 332 million gallons per year (mmgy).
	The biomass-based diesel industry and the Company’s business have benefited from certain federal and state incentives. The federal biomass-based diesel mixture excise tax credit (BTC) expired on December 31, 2013 and it is uncertain whether it will be reinstated. This expiration, along with other amendments of any one or more of those laws or incentives, could adversely affect the financial results of the Company.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
Summary of Significant Accounting Policies	'
	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
	We have disclosed a summary of the Company's significant accounting policies in the December 31, 2013 Annual Report on Form 10-K. There have been no material changes from the policies previously disclosed other than those noted below.
	Restricted Cash
	Restricted cash consists of $101,315 of cash, which is held in a certificate of deposit and 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, $3,500 is held in a certificate of deposit and pledged to Bank of America, who issued a letter of credit to support REG Energy Services' trade activities as of September 30, 2014. There was no restricted cash balance at December 31, 2013. For additional information, see "Note 9 - Debt". The Company classifies restricted cash between current and non-current assets based on the length of time of the restricted use.
	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. A decline of fair value below amortized costs of debt securities is considered an other-than-temporary impairment if the Company has the intent to sell the security or it is more likely than not that the Company will be required to sell the security before recovery of the entire amortized cost basis. In those instances, an impairment charge equal to the difference between the fair value and the amortized cost basis is recognized in earnings. Regardless of the Company’s intent or requirement to sell a debt security, an impairment is considered other-than-temporary if the Company does not expect to recover the entire amortized cost basis; in those instances, a credit loss equal to the difference between the present value of the cash flows expected to be collected based on credit risk and the amortized cost basis of the debt security is recognized in earnings. The Company has no current requirement or intent to sell a material portion of marketable securities as of September 30, 2014. The Company expects to recover up to (or beyond) the initial cost of investment for securities held. In computing realized gains and losses on available-for-sale securities, the Company determines cost based on amounts paid, including direct costs such as commissions to acquire the security, using the specific identification method. There were no gross realized gains and losses on available-for-sale securities during the three and nine months ended September 30, 2014 and 2013.
	Inventories
	Inventories are valued at the lower of cost or market. Lower of cost or market adjustments amounting to $1,051 and $0 were made to the inventory values reported as of September 30, 2014 and December 31, 2013, respectively. Cost is determined based on the first-in, first-out method.
	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 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 value of the Company’s reporting units. 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 annual impairment test determined that the fair value of the biodiesel reporting unit exceeded its carrying value by approximately 7% and the services reporting unit exceeded its carrying value by approximately 66%. There have been no impairment indicators in the first nine months of 2014 that would indicate that an additional assessment needs be taken.
	Contingent Consideration for Acquisitions
	Contingent considerations in a purchase business combination are established at the time of the acquisition (See "Note 3 - Acquisitions and Equity Transactions"). 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 Condensed Consolidated Statements of Operations.
	Research and Development Costs
	Research and development (R&D) costs are charged to expense as incurred and included in Selling, General and Administrative expenses on the Condensed Consolidated Statements of Operations. R&D expense was $2,810 and $7,900 for the three and nine months ended September 30, 2014, respectively, and $79 and $153 for the three and nine months ended September 30, 2013, respectively. In process research and development (IPR&D) assets acquired in connection with acquisitions are recorded on the Condensed 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.
	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 9 - 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.
	Income Taxes
	The tax benefit for the nine months ended September 30, 2014 was mainly attributable to the acquisition of Syntroleum and Dynamic Fuels. Specifically, in connection with the acquisition of Syntroleum and Dynamic Fuels, the Company acquired a net deferred tax liability of $7,278 that will produce future taxable income. The increase in the gross deferred tax liability resulted in a reduction to the Company's valuation allowance which was recognized as a tax benefit discretely in the quarter ended June 30, 2014.
	Under the rules prescribed by Internal Revenue Code (IRC) Section 382 and applicable regulations, if certain transactions occur with respect to an entity's capital stock that result in a cumulative ownership shift of more than 50% by 5% stockholders over a testing period, annual limitations are imposed with respect to the entity's ability to utilize its net operating loss carryforwards. During the nine months ended September 30, 2014, the Company recorded an increase to the deferred tax assets for net operating loss carryforwards from Syntroleum of approximately $22,600 on a pre-tax basis (after IRC Section 382 limitation). IRC Section 382 limits the Company's ability to realize these net operating losses, which begin to expire in 2018 and, accordingly, the Company has recorded a full valuation allowance on the net operating loss carryforwards. As described in Note 3, the Company has not completed its accounting for the business combinations related to the Syntroleum and Dynamic Fuels acquisitions, and we continue to assess the recognition, measurement, and realizability of these deferred tax assets, and any changes thereto will be recorded in the accounting for the business combination.
	New Accounting Standards
	In May 2014, the FASB issued 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. The guidance in this update supersedes the revenue recognition requirements in ASC Topic 605, Revenue Recognition, and most industry-specific guidance throughout the industry topics of the codification. For public companies, this update will be effective for interim and annual periods beginning after December 15, 2016. The Company is currently still assessing the impact that this guidance will have on its consolidated financial statements.

Acquisitions_and_Equity_Transa

Acquisitions and Equity Transactions	9 Months Ended
	Sep. 30, 2014
Business Combinations [Abstract]	'
Acquisitions and Equity Transactions	'
	ACQUISITIONS AND EQUITY TRANSACTIONS
	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. The Company has completed its initial accounting for this business combination in the second quarter when the valuation of the contingent consideration, in-process research & development intangible assets and goodwill acquired was finalized. The following table summarizes the consideration paid for LS9 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
		22-Jan-14
	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 September 30, 2014, the Company has recorded a contingent liability of $15,474, all of which has been classified as non-current on the Condensed Consolidated Balance Sheets.
	The goodwill acquired is included in the Biodiesel segment, a portion of which is expected to be deductible for tax purposes.
	REG Life Sciences had no revenues for the three and nine months ended September 30, 2014. The net loss generated by REG Life Sciences for the three and nine months ended September 30, 2014, included in the Condensed Consolidated Statements of Operations was $3,863 and $8,527, respectively.
	Syntroleum Corporation/Dynamic Fuels, LLC
	On June 3, 2014, REG Synthetic Fuels, a wholly-owned subsidiary of the Company included in the Biodiesel 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 million gallon per year nameplate capacity renewable hydrocarbon diesel biorefinery located in Geismar, Louisiana. The Company has not completed its initial accounting for this business combination as the valuation of the intangible assets and goodwill acquired has not been finalized. 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 Biodiesel segment. The Company has not completed its initial accounting for this business combination as the valuation of the real and personal property, contingent consideration, intangible assets and goodwill acquired has not been finalized.
	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:
		6-Jun-14
	Assets (liabilities) acquired of Syntroleum and Dynamic Fuels:
	Cash	$	253
	Other current assets	4,666
	Property, plant and equipment	122,827
	Goodwill	55,762
	Intangible assets	8,900
	Other noncurrent assets	10,281
	Other current liabilities	(1,180		)
	Deferred tax liabilities	(7,278		)
	Debt	(113,553		)
	Other noncurrent liabilities	(500		)
	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 September 30, 2014, the Company has recorded a contingent liability of $29,033, of which $5,096 has been classified in accrued expenses and other liabilities on the Condensed Consolidated Balance Sheets.
	The goodwill acquired is included in the Biodiesel segment, a portion of which is expected to be deductible for tax purposes.
	REG Synthetic Fuels, including its wholly-owned subsidiary REG Geismar, had $262 and $312 in revenues for the three and nine months ended September 30, 2014, respectively. The net loss generated by REG Synthetic Fuels for the three and nine months ended September 30, 2014 included in the Condensed Consolidated Statement of Operations was $4,766 and $9,617, respectively, which includes $3,004 of income tax expense for the nine months ended September 30, 2014, resulting from the recording of a valuation allowance offsetting their deferred tax assets.
	The following pro forma condensed combined results of operations assume that LS9, Syntroleum and Dynamic Fuels acquisitions were completed as of January 1, 2013:
		Three Months			Three Months		Nine Months			Nine Months
		Ended			Ended		Ended			Ended
		September 30,			September 30,		September 30,			September 30,
		2014			2013		2014			2013
	Revenues	$	384,258		$	458,463	$	936,759		$	1,135,692
	Net income (loss)	4,504			67,746		(497		)	131,688
	Basic net income (loss) per share	$	0.11		$	1.77	$	(0.01	)	$	3.54
	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.

Marketable_Securities_Notes

Marketable Securities (Notes)	9 Months Ended
	Sep. 30, 2014
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 following table summarizes the Company's marketable securities:
		As of September 30, 2014
		Maturity	Gross Amortized Cost		Total Unrealized Gains		Total Unrealized Losses			Fair Value
	Commercial paper	Within one year	$	19,473	$	7	$	(4	)	$	19,476
	Corporate bonds	Within one year	30,243		—		(9		)	30,234
	Certificates of deposit	Within one year	11,680		—		(12		)	11,668
	Total		$	61,396	$	7	$	(25	)	$	61,378

Inventories

Inventories	9 Months Ended
	Sep. 30, 2014
Inventory Disclosure [Abstract]	'
Inventories	'
	INVENTORIES
	Inventories consist of the following:
		30-Sep-14		31-Dec-13
	Raw materials	$	22,923	$	13,393
	Work in process	1,722		1,456
	Finished goods	24,737		70,965
	Total	$	49,382	$	85,814

Prepaid_Expenses_and_Other_Ass

Prepaid Expenses and Other Assets	9 Months Ended
	Sep. 30, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]	'
Prepaid Expenses and Other Assets	'
	PREPAID EXPENSES AND OTHER ASSETS
	Prepaid expense and other assets consist of the following:
		30-Sep-14		31-Dec-13
	Commodity derivatives and related collateral, net	$	14,069	$	13,675
	Prepaid expenses	5,172		2,414
	Deposits	4,314		293
	RIN inventory	11,753		6,455
	Income taxes receivable	2,028		2,197
	Other	2,450		534
	Total	$	39,786	$	25,568
	RIN inventory values were adjusted in the amount of $260 and $1,277 at September 30, 2014 and December 31, 2013, respectively, to reflect the lower of cost or market.
	Other noncurrent assets consist of the following:
		September 30, 2014		December 31, 2013
	Investments	$	10,003	$	7,351
	Debt issuance costs (net of accumulated amortization of $1,207 and $715, respectively)	4,837		832
	Spare parts inventory	3,671		3,671
	Deposits	3,870		—
	Other	6,975		526
	Total	$	29,356	$	12,380

Goodwill_Notes

Goodwill (Notes)	9 Months Ended
	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill	'
	GOODWILL
	The following table shows the carrying amount of goodwill by reportable segment as of December 31, 2013 and the changes in goodwill for the nine months ended September 30, 2014:
		Biodiesel		Services		Total
	Balance, December 31, 2013	$	68,784	$	16,080	$	84,864
	Acquisitions	90,608		—		90,608
	Balance, September 30, 2014	$	159,392	$	16,080	$	175,472

Intangible_Assets

Intangible Assets	9 Months Ended
	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Intangible Assets	'
	INTANGIBLE ASSETS
	Intangible assets consist of the following:
		30-Sep-14
		Cost		Accumulated Amortization			Net		Weighted Average Remaining Life
	Raw material supply agreement	$	5,818	$	(1,017	)	$	4,801	11.3 years
	Renewable hydrocarbon diesel technology	8,300		(184		)	8,116		14.8 years
	Trademarks	600		(300		)	300		0.3 years
	Ground lease	200		(93		)	107		7.1 years
	Total amortizing intangibles	14,918		(1,594		)	13,324
	In-process research and development, indefinite lives	15,956		—			15,956
	Total intangible assets	$	30,874	$	(1,594	)	$	29,280
		31-Dec-13
		Cost		Accumulated Amortization			Net		Weighted Average Remaining Life
	Raw material supply agreement	$	5,502	$	(753	)	$	4,749	12.0 years
	Ground lease	200		(82		)	118		7.9 years
	Total amortizing intangibles	5,702		(835		)	4,867
	In-process research and development, indefinite lives	—		—			—
	Total intangible assets	$	5,702	$	(835	)	$	4,867
	The Company recorded intangible amortization expense of $583 and $760 for the three and nine months ended September 30, 2014, respectively, and $89 and $236 for the three and nine months ended September 30, 2013, respectively.
	The estimated intangible asset amortization expense for fiscal year 2014 through fiscal year 2019 and thereafter is as follows:
	October 1, 2014 through December 31, 2014	$	542
	2015	1,038
	2016	1,052
	2017	1,067
	2018	1,082
	2019 and thereafter	8,543
	Total	$	13,324

Debt

Debt	9 Months Ended
	Sep. 30, 2014
Debt Disclosure [Abstract]	'
Debt	'
	DEBT
	The Company’s debt is as follows:
		30-Sep-14		31-Dec-13
	Convertible debt	$	120,207	$	—
	REG Geismar GOZone bonds	100,000		—
	REG Danville term loan	2,113		5,626
	REG Newton term loan	15,524		18,143
	REG Mason City term loan	4,710		5,135
	Other	5,046		1,247
	Total debt	$	247,600	$	30,151
	Bell, LLC promissory note—variable interest entity	$	—	$	4,029
	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 Convertible Notes bear interest at a rate of 2.75% per annum, payable semi-annually in arrears on June 15 and December 15 of each year, beginning December 15, 2014.
	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. In addition, following certain corporate events that occur prior to the stated maturity date, the Company will increase the conversion rate for a holder who elects to convert in connection with such a corporate event in certain circumstances.
	Prior to December 15, 2018, holders may convert all or any portion of their Convertible Notes only under the following circumstances: (1) during any calendar quarter commencing after the calendar quarter ending on September 30, 2014 (and only during such calendar quarter), if the last reported sale price of the Common Stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price of the Convertible Notes on each applicable trading day; (2) during the five business day period after any five consecutive trading day period in which the trading price per $1,000 principal amount of Convertible Notes for each trading day of such five consecutive trading day period was 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 such trading day; or (3) 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. If the Company satisfies its conversion obligation solely in cash or through payment and delivery, as the case may be, of a combination of cash and shares of Common Stock, the amount of cash and shares of Common Stock, if any, due upon conversion will be based on a daily conversion value calculated for each trading day in an 80 trading day observation period. The Company's 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).
	Upon a fundamental change, subject to certain conditions, holders may require the Company to repurchase for cash all or a portion of their Convertible Notes at a purchase price in cash that will generally be equal to 100% of the principal amount of the Convertible Notes to be repurchased, plus any accrued and unpaid interest to, but excluding, the fundamental change repurchase date. 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 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) for the purpose of reducing potential dilution of earnings per share if the Convertible Notes were to be converted to shares of Common Stock. 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 Capped Call is expected generally to reduce the potential dilution to the Common Stock and/or offset potential cash payments the Company is required to make in excess of the principal amount to the extent of such percentage upon conversion of the Convertible Notes in the event that the market price per share of the Common Stock, as measured under the terms of the Capped Call, is greater than the strike price of the Capped Call, which initially corresponds to the conversion price of the Convertible Notes and is subject to anti-dilution adjustments substantially similar to those applicable to the conversion rate of the Convertible Notes, with such reduction and/or offset subject to a cap in the event that the market price per share of the Common Stock, as measured under the terms of the Capped Call, is greater than the cap price of the Capped Call.
	The Company will not be required to make any cash payments to the Option Counterparties or their respective affiliates upon the exercise of the options that are a part of the Capped Call, but the Company will be entitled to receive from them a number of shares of Common Stock and/or an amount of cash generally based on the amount by which the market price per share of the Common Stock, as measured under the terms of the Capped Call, is greater than the strike price of the Capped Call during the relevant valuation period under the Capped Call, with such number of shares of Common Stock and amounts of cash, if any, subject to the cap.
	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
	In October 2008, Dynamic Fuels received $100,000 in proceeds from the issuance of GOZone Bonds by the Louisiana Public Facilities Authority (the Authority) pursuant to a loan agreement between Dynamic Fuels and the Authority (Loan Agreement). The proceeds were used to construct the Dynamic Fuels production facility. In June 2014, as a result of the acquisitions of Syntroleum and Dynamic Fuels, the Loan Agreement related to the GOZone Bonds became part of the Company's consolidated long-term debt. The GOZone Bonds mature on October 1, 2033. Interest on the GOZone Bonds accrues at a daily rate, weekly rate, commercial paper rate or long term rate, as determined by REG Geismar. When the GOZone Bonds are in daily or weekly mode, at any time holders have the right to tender bonds for repurchase and bonds are subject to optional redemption by a remarketing agent pursuant to a remarketing agreement. The GOZone Bonds were in the weekly interest rate mode as of September 30, 2014 and the applicable interest rate at September 30, 2014 was 0.04% per annum.
	At the time that the GOZone Bonds were originally issued, Tyson Foods, one of the former equityholders of Dynamic Fuels, obtained an irrevocable direct-pay letter of credit (Old Letter of Credit) from a financial institution which was provided to the trustee for the GOZone Bonds and drawn upon to pay the principal of and interest on the GOZone Bonds and the portion of the purchase price attributable to principal of and interest on the GOZone Bonds in connection with any GOZone Bond repurchase obligations of Dynamic Fuels. In connection with the acquisition from Tyson Foods, the Company agreed to reimburse Tyson Foods for any amounts payable by Tyson in the event of a draw on the Old Letter of Credit, to replace the Old Letter of Credit or redeem or discharge the GOZone Bonds and to secure these obligations by the deposit of $101,315 into an escrow account for the benefit of Tyson, which represented the full amount of Tyson’s obligation under the Old Letter of Credit.
	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, which represents the sum of the outstanding $100,000 principal amount of the GOZone Bonds plus $1,315 of interest. 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 Condensed Consolidated Balance Sheets. The Substitute Letter of Credit expires on July 8, 2015. 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.
	Revolving Line of Credit
		September 30, 2014		December 31, 2013
	Amount borrowed under revolving line of credit	$	—	$	10,986
	Maximum available to be borrowed under revolving line of credit	$	35,975	$	29,014

Related_Party_Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2014
Related Party Transactions [Abstract]	'
Related Party Transactions	'
	RELATED PARTY TRANSACTIONS
	West Central Cooperative
	West Central beneficially owns more than 5% of our outstanding securities. The Company has several contractual relationships and transactions with West Central, including contracts for services, supply of soybean oil feedstock, a ground lease for the Ralston facility and an extended payment terms arrangement.
	Under the ground lease with West Central, West Central leases the real property on which the Ralston facility is located for an annual rental fee of one dollar. The ground lease has a 20-year term ending July 31, 2026 and the Company may elect to extend the term for six additional five-year terms. The Company also has an Asset Use Agreement with West Central which 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 purchases once-refined soybean oil from West Central to supply the Ralston facility. On October 1, 2012, the Company entered into a new feedstock supply agreement with West Central. The supply agreement expired on January 31, 2014 with the option for a one year extension, which the Company extended. West Central agrees to supply and the Company agrees to purchase soybean oil for the Ralston facility at a price indexed to prevailing Chicago Board of Trade, or CBOT, soybean oil market prices with an agreed upon negotiated market basis.
	In June 2009, the Company entered into an extended payment terms agreement with West Central. The agreement set forth the terms of payment that apply for soybean oil that West Central sold to the Company for use at the Ralston facility, as well as any other feedstock that West Central agreed to sell. Pursuant to the agreement, payment for feedstocks delivered by West Central is required to be made within 45 days after delivery by West Central of an invoice for the feedstocks. Interest accrues on amounts due for feedstocks supplied by West Central beginning on the fifth day after West Central delivered an invoice for the feedstock until paid. At no time during the term of the agreement is the amount payable to West Central permitted to exceed $3,000. The agreement expires in January 2015 and automatically renews for one additional year unless either party provides sufficient notice of cancellation prior to the renewal.
	Summary of Related Party Balances - Condensed Consolidated Statements of Operations
		Three Months		Three Months		Nine Months		Nine Months
		Ended		Ended		Ended		Ended
		September 30,		September 30,		September 30,		September 30,
		2014		2013		2014		2013
	Cost of goods sold – Biodiesel	$	10,490	$	12,057	$	31,919	$	37,198
	Selling, general and administrative expenses	$	4	$	—	$	43	$	2
	Interest expense	$	1	$	2	$	2	$	30
	Summary of Related Party Balances - Condensed Consolidated Balance Sheets
		As of		As of
		September 30, 2014		December 31, 2013
	Accounts receivable	$	141	$	426
	Other assets	$	—	$	35
	Accounts payable	$	570	$	552

Derivative_Instruments

Derivative Instruments	9 Months Ended
	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivative Instruments	'
	DERIVATIVE INSTRUMENTS
	The Company enters into heating oil and soybean oil futures, swaps and options (commodity contract derivatives) to hedge its exposure to price risk related to anticipated purchases of feedstock raw materials and to protect gross profit margins from potentially adverse effects of price volatility on biodiesel sales where prices are set at a future date. All of the Company’s commodity contract derivatives are designated as non-hedge derivatives and recorded at fair value on the Condensed Consolidated Balance Sheets. Unrealized gains and losses are recognized as a component of biodiesel costs of goods sold reflected in current results of operations. As of September 30, 2014, the Company had 2,255 open commodity contracts.
	The Company offsets the fair value amounts recognized for its commodity contract derivatives with cash collateral with the same counterparty under a master netting agreement. The net position is presented within prepaid and other assets in the Condensed Consolidated Balance Sheets. The following table sets forth the fair value of the Company's commodity contract derivatives and amounts that offset within the Condensed Consolidated Balance Sheets:
		30-Sep-14								31-Dec-13
		Assets				Liabilities				Assets				Liabilities
	Gross amounts of derivatives recognized at fair value	$	11,019			$	210			$	325			$	546
	Cash collateral	3,763				503				13,896				—
	Total gross amount recognized	14,782				713				14,221				546
	Gross amounts offset	(713		)		(713		)		(546		)		(546		)
	Net amount reported in the condensed consolidated balance sheet	$	14,069			$	—			$	13,675			$	—
	The following table sets forth the pre-tax gains (losses) included in the Condensed Consolidated Statements of Operations:
		Location of Gain (Loss)		Three Months				Three Months				Nine Months				Nine Months
		Recognized in income		Ended				Ended				Ended				Ended
				September 30,				September 30,				September 30,				September 30,
				2014				2013				2014				2013
	Commodity derivatives	Cost of goods sold – Biodiesel		$	19,249			$	(11,209	)		$	15,811			$	(3,170	)

Fair_Value_Measurement

Fair Value Measurement	9 Months Ended
	Sep. 30, 2014
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 September 30, 2014
		Total			Level 1			Level 2			Level 3
	Money market funds	$	561		$	561		$	—		$	—
	Certificates of deposit	11,668			—			11,668			—
	Commercial paper	19,476			—			19,476			—
	Commercial notes/bonds	30,234			—			30,234			—
	Commodity contract derivatives	10,809			3,264			7,545			—
	Contingent consideration for LS9 acquisition	(15,474		)	—			—			(15,474		)
	Contingent consideration for Dynamic Fuels acquisition	(29,033		)	—			—			(29,033		)
		As of December 31, 2013
		Total			Level 1			Level 2			Level 3
	Commodity contract derivatives	$	(221	)	$	—		$	(221	)	$	—
	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):
		Contingent Consideration for LS9 Acquisition			Contingent Consideration for Dynamic Fuels Acquisition
	Beginning balance - January 1, 2014	$	—		$	—
	Fair value of contingent liability recorded at measurement date	17,050			—
	Ending balance - March 31, 2014	17,050			—
	Fair value of contingent liability recorded at measurement date	—			28,900
	Change in estimates included in earnings	(384		)	—
	Settlements	—			—
	Ending balance - June 30, 2014	16,666			28,900
	Change in estimates included in earnings	(1,192		)	133
	Settlements	—			—
	Ending balance - September 30, 2014	$	15,474		$	29,033
	The estimated fair values of the Company’s financial instruments, which are not recorded at fair value, are as follows:
		As of September 30, 2014						As of December 31, 2013
		Asset (Liability)			Fair Value			Asset (Liability)			Fair Value
		Carrying						Carrying
		Amount						Amount
	Financial liabilities:
	Debt and lines of credit	$	(247,600	)	$	(247,915	)	$	(45,166	)	$	(45,094	)
	The carrying amounts reported in the Condensed Consolidated Balance Sheets for cash and cash equivalents, accounts receivable, accounts payable and accrued expenses approximate their fair values. Money market funds are included in cash and cash equivalents on the Condensed Consolidated Balance Sheets.
	The Company used the following methods and assumptions to estimate fair value of its financial instruments:
	Marketable securities: The fair value of marketable securities 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 derivatives: The instruments held by the Company consist primarily of futures contracts, swap agreements, purchased put options and written call options. The 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 should the achievement of certain milestones related to the sale 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.
	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.

Net_Income_Per_Share

Net Income Per Share	9 Months Ended
	Sep. 30, 2014
Earnings Per Share [Abstract]	'
Net Income Per Share	'
	NET INCOME 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 B Preferred Stock and restricted stock units (RSUs).
	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:
		Three Months		Three Months			Nine Months		Nine Months
		Ended		Ended			Ended		Ended
		September 30,		September 30,			September 30,		September 30,
		2014		2013			2014		2013
	Options to purchase common stock	87,026		87,026			87,026		87,026
	Restricted stock units	—		—			—		—
	Stock appreciation rights	1,137,743		314,036			1,401,144		1,194,477
	Warrants to purchase common stock	—		—			17,916		—
	Convertible notes	10,838,218		—			4,764,052		—
	Total	12,062,987		401,062			6,270,138		1,281,503
	The following table presents the calculation of diluted net income per share:
		Three Months			Three Months			Nine Months			Nine Months
		Ended			Ended			Ended			Ended
		September 30,			September 30,			September 30,			September 30,
		2014			2013			2014			2013
	Net income attributable to the Company’s common stockholders - Basic	$	4,504		$	78,462		$	13,362		$	133,958
	Plus: change in undistributed dividends allocated to preferred stockholders	—			147			—			147
	Plus: distributed dividends to Preferred Stockholders	—			258			40			1,848
	Plus (Less): effect of participating securities	—			(355		)	(406		)	(1,992		)
	Net income available to common stockholders - Dilutive	$	4,504		$	78,512		$	12,996		$	133,961
	Shares:
	Weighted-average shares used to compute basic net income per share	42,374,768			33,790,034			40,216,467			31,918,951
	Adjustment to reflect warrants to purchase common stock	17,916			4,533			—			269
	Adjustment to reflect stock appreciation right conversions	39,321			221,909			12,462			4,977
	Weighted-average shares used to compute diluted net income per share	42,432,005			34,016,476			40,228,929			31,924,197
	Net income per share attributable to common stockholders:
	Diluted	$	0.11		$	2.31		$	0.32		$	4.2

Reportable_Segments

Reportable Segments	9 Months Ended
	Sep. 30, 2014
Segment Reporting [Abstract]	'
Reportable Segments	'
	REPORTABLE SEGMENTS
	The Company reports its reportable segments based on products and services provided to customers, which include Biodiesel, Services and Corporate and other. The accounting policies of the segments are the same as those described in the summary of significant accounting policies. The Company has chosen to differentiate the reportable segments based on the products and services each segment offers.
	The Biodiesel segment processes waste vegetable oils, animal fats, virgin vegetable oils and other feedstocks and methanol into biomass-based diesel. The Biodiesel segment also includes the Company’s purchases and resale of biomass-based diesel produced by third parties. Revenues are derived from the purchases and sales of biomass-based diesel 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, sales of RINs, related by-products and renewable energy government incentive payments. The Services segment offers services for managing the construction of biomass-based diesel production facilities and managing ongoing operations of internal and 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. Intersegment revenues are reported by the Services segment, which manages the construction and operations of facilities included in the Biodiesel segment. Revenues are recorded by the Services segment at cost. Corporate expenses consist of corporate office expenses including compensation, benefits, occupancy and other administrative costs, including management service expenses.
	The following table represents the significant items by reportable segment:
		Three Months			Three Months			Nine Months			Nine Months
		Ended			Ended			Ended			Ended
		September 30,			September 30,			September 30,			September 30,
		2014			2013			2014			2013
	Net revenues:
	Biodiesel	$	384,126		$	458,429		$	935,997		$	1,107,443
	Services	25,422			17,854			72,012			46,809
	Intersegment revenues	(25,290		)	(17,839		)	(71,793		)	(46,705		)
		$	384,258		$	458,444		$	936,216		$	1,107,547
	Income (loss) before income taxes:
	Biodiesel	$	22,603		$	57,854		$	49,278		$	194,770
	Services	112			(5		)	152			(45		)
	Corporate and other (a)	(18,391		)	(13,197		)	(48,484		)	(35,037		)
		$	4,324		$	44,652		$	946		$	159,688
	Depreciation and amortization expense, net:
	Biodiesel	$	3,509		$	2,214		$	8,934		$	5,854
	Services	55			35			148			86
	Corporate and other (a)	335			237			856			669
		$	3,899		$	2,486		$	9,938		$	6,609
	Cash paid for purchases of property, plant and equipment:
	Biodiesel	$	9,749		$	8,363		$	40,655		$	26,573
	Services	12			30			643			504
	Corporate and other (a)	3,508			335			4,281			1,708
		$	13,269		$	8,728		$	45,579		$	28,785
		As of			As of
		September 30, 2014			December 31, 2013
	Assets:
	Biodiesel	$	801,106		$	444,945
	Services	21,036			20,542
	Corporate and other (b)	233,542			275,368
		$	1,055,684		$	740,855
	(a)	Corporate and other includes income/(expense) not associated with the reportable segments, such as corporate general and administrative expenses, shared service expenses, interest expense and interest income.
	(b)	Corporate and other includes cash and other assets not associated with the reportable segments, including investments.

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2014
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.
	October 1, 2014 through December 31, 2014	$	958
	2015	3,857
	2016	3,857
	2017	3,857
	2018	3,784
	2019 and thereafter	19,591
	Total	$	35,904
	As of September 30, 2014, REG Geismar relies on one supplier to provide hydrogen necessary to execute the production process. Any disruptions to the hydrogen supply 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.
	******

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2014
Accounting Policies [Abstract]	'
Restricted Cash	'
	Restricted Cash
	Restricted cash consists of $101,315 of cash, which is held in a certificate of deposit and 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, $3,500 is held in a certificate of deposit and pledged to Bank of America, who issued a letter of credit to support REG Energy Services' trade activities as of September 30, 2014. There was no restricted cash balance at December 31, 2013. For additional information, see "Note 9 - Debt". The Company classifies 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. A decline of fair value below amortized costs of debt securities is considered an other-than-temporary impairment if the Company has the intent to sell the security or it is more likely than not that the Company will be required to sell the security before recovery of the entire amortized cost basis. In those instances, an impairment charge equal to the difference between the fair value and the amortized cost basis is recognized in earnings. Regardless of the Company’s intent or requirement to sell a debt security, an impairment is considered other-than-temporary if the Company does not expect to recover the entire amortized cost basis; in those instances, a credit loss equal to the difference between the present value of the cash flows expected to be collected based on credit risk and the amortized cost basis of the debt security is recognized in earnings. The Company has no current requirement or intent to sell a material portion of marketable securities as of September 30, 2014. The Company expects to recover up to (or beyond) the initial cost of investment for securities held. In computing realized gains and losses on available-for-sale securities, the Company determines cost based on amounts paid, including direct costs such as commissions to acquire the security, using the specific identification method. There were no gross realized gains and losses on available-for-sale securities during the three and nine months ended September 30, 2014 and 2013.
Inventories	'
	Inventories
	Inventories are valued at the lower of cost or market. Lower of cost or market adjustments amounting to $1,051 and $0 were made to the inventory values reported as of September 30, 2014 and December 31, 2013, respectively. Cost is determined based on the first-in, first-out method.
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 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 value of the Company’s reporting units. 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 annual impairment test determined that the fair value of the biodiesel reporting unit exceeded its carrying value by approximately 7% and the services reporting unit exceeded its carrying value by approximately 66%. There have been no impairment indicators in the first nine months of 2014 that would indicate that an additional assessment needs be taken.
Contingent Consideration for Acquisitions	'
	Contingent Consideration for Acquisitions
	Contingent considerations in a purchase business combination are established at the time of the acquisition (See "Note 3 - Acquisitions and Equity Transactions"). 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 Condensed Consolidated Statements of Operations.
Research and Development Costs	'
	Research and Development Costs
	Research and development (R&D) costs are charged to expense as incurred and included in Selling, General and Administrative expenses on the Condensed Consolidated Statements of Operations. R&D expense was $2,810 and $7,900 for the three and nine months ended September 30, 2014, respectively, and $79 and $153 for the three and nine months ended September 30, 2013, respectively. In process research and development (IPR&D) assets acquired in connection with acquisitions are recorded on the Condensed 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.
Convertible Debt	'
	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 9 - Debt" for further descriptions of the transaction.
Capped Call 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.
Income Taxes	'
	Income Taxes
	The tax benefit for the nine months ended September 30, 2014 was mainly attributable to the acquisition of Syntroleum and Dynamic Fuels. Specifically, in connection with the acquisition of Syntroleum and Dynamic Fuels, the Company acquired a net deferred tax liability of $7,278 that will produce future taxable income. The increase in the gross deferred tax liability resulted in a reduction to the Company's valuation allowance which was recognized as a tax benefit discretely in the quarter ended June 30, 2014.
	Under the rules prescribed by Internal Revenue Code (IRC) Section 382 and applicable regulations, if certain transactions occur with respect to an entity's capital stock that result in a cumulative ownership shift of more than 50% by 5% stockholders over a testing period, annual limitations are imposed with respect to the entity's ability to utilize its net operating loss carryforwards. During the nine months ended September 30, 2014, the Company recorded an increase to the deferred tax assets for net operating loss carryforwards from Syntroleum of approximately $22,600 on a pre-tax basis (after IRC Section 382 limitation). IRC Section 382 limits the Company's ability to realize these net operating losses, which begin to expire in 2018 and, accordingly, the Company has recorded a full valuation allowance on the net operating loss carryforwards. As described in Note 3, the Company has not completed its accounting for the business combinations related to the Syntroleum and Dynamic Fuels acquisitions, and we continue to assess the recognition, measurement, and realizability of these deferred tax assets, and any changes thereto will be recorded in the accounting for the business combination.
New Accounting Pronouncements	'
	New Accounting Standards
	In May 2014, the FASB issued 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. The guidance in this update supersedes the revenue recognition requirements in ASC Topic 605, Revenue Recognition, and most industry-specific guidance throughout the industry topics of the codification. For public companies, this update will be effective for interim and annual periods beginning after December 15, 2016. The Company is currently still assessing the impact that this guidance will have on its consolidated financial statements.

Acquisitions_and_Equity_Transa1

Acquisitions and Equity Transactions (Tables)	9 Months Ended
	Sep. 30, 2014
Business Combinations [Abstract]	'
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
	The following table summarizes the consideration paid for LS9 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
		22-Jan-14
	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
		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:
		6-Jun-14
	Assets (liabilities) acquired of Syntroleum and Dynamic Fuels:
	Cash	$	253
	Other current assets	4,666
	Property, plant and equipment	122,827
	Goodwill	55,762
	Intangible assets	8,900
	Other noncurrent assets	10,281
	Other current liabilities	(1,180		)
	Deferred tax liabilities	(7,278		)
	Debt	(113,553		)
	Other noncurrent liabilities	(500		)
	Total	$	80,178
Acquisition, Pro Forma Information	'
	The following pro forma condensed combined results of operations assume that LS9, Syntroleum and Dynamic Fuels acquisitions were completed as of January 1, 2013:
		Three Months			Three Months		Nine Months			Nine Months
		Ended			Ended		Ended			Ended
		September 30,			September 30,		September 30,			September 30,
		2014			2013		2014			2013
	Revenues	$	384,258		$	458,463	$	936,759		$	1,135,692
	Net income (loss)	4,504			67,746		(497		)	131,688
	Basic net income (loss) per share	$	0.11		$	1.77	$	(0.01	)	$	3.54

Marketable_Securities_Tables

Marketable Securities (Tables)	9 Months Ended
	Sep. 30, 2014
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 following table summarizes the Company's marketable securities:
		As of September 30, 2014
		Maturity	Gross Amortized Cost		Total Unrealized Gains		Total Unrealized Losses			Fair Value
	Commercial paper	Within one year	$	19,473	$	7	$	(4	)	$	19,476
	Corporate bonds	Within one year	30,243		—		(9		)	30,234
	Certificates of deposit	Within one year	11,680		—		(12		)	11,668
	Total		$	61,396	$	7	$	(25	)	$	61,378

Inventories_Tables

Inventories (Tables)	9 Months Ended
	Sep. 30, 2014
Inventory Disclosure [Abstract]	'
Inventories	'
	Inventories consist of the following:
		30-Sep-14		31-Dec-13
	Raw materials	$	22,923	$	13,393
	Work in process	1,722		1,456
	Finished goods	24,737		70,965
	Total	$	49,382	$	85,814

Prepaid_Expenses_and_Other_Ass1

Prepaid Expenses and Other Assets (Tables)	9 Months Ended
	Sep. 30, 2014
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]	'
Summary of Prepaid Expense and Other Assets	'
	Prepaid expense and other assets consist of the following:
		30-Sep-14		31-Dec-13
	Commodity derivatives and related collateral, net	$	14,069	$	13,675
	Prepaid expenses	5,172		2,414
	Deposits	4,314		293
	RIN inventory	11,753		6,455
	Income taxes receivable	2,028		2,197
	Other	2,450		534
	Total	$	39,786	$	25,568
Summary of other noncurrent assets	'
	Other noncurrent assets consist of the following:
		September 30, 2014		December 31, 2013
	Investments	$	10,003	$	7,351
	Debt issuance costs (net of accumulated amortization of $1,207 and $715, respectively)	4,837		832
	Spare parts inventory	3,671		3,671
	Deposits	3,870		—
	Other	6,975		526
	Total	$	29,356	$	12,380

Goodwill_Tables

Goodwill (Tables)	9 Months Ended
	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Carrying amount of goodwill	'
	The following table shows the carrying amount of goodwill by reportable segment as of December 31, 2013 and the changes in goodwill for the nine months ended September 30, 2014:
		Biodiesel		Services		Total
	Balance, December 31, 2013	$	68,784	$	16,080	$	84,864
	Acquisitions	90,608		—		90,608
	Balance, September 30, 2014	$	159,392	$	16,080	$	175,472

Intangible_Assets_Tables

Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Components of Intangible assets	'
	Intangible assets consist of the following:
		30-Sep-14
		Cost		Accumulated Amortization			Net		Weighted Average Remaining Life
	Raw material supply agreement	$	5,818	$	(1,017	)	$	4,801	11.3 years
	Renewable hydrocarbon diesel technology	8,300		(184		)	8,116		14.8 years
	Trademarks	600		(300		)	300		0.3 years
	Ground lease	200		(93		)	107		7.1 years
	Total amortizing intangibles	14,918		(1,594		)	13,324
	In-process research and development, indefinite lives	15,956		—			15,956
	Total intangible assets	$	30,874	$	(1,594	)	$	29,280
		31-Dec-13
		Cost		Accumulated Amortization			Net		Weighted Average Remaining Life
	Raw material supply agreement	$	5,502	$	(753	)	$	4,749	12.0 years
	Ground lease	200		(82		)	118		7.9 years
	Total amortizing intangibles	5,702		(835		)	4,867
	In-process research and development, indefinite lives	—		—			—
	Total intangible assets	$	5,702	$	(835	)	$	4,867
Estimated amortization expense	'
	The estimated intangible asset amortization expense for fiscal year 2014 through fiscal year 2019 and thereafter is as follows:
	October 1, 2014 through December 31, 2014	$	542
	2015	1,038
	2016	1,052
	2017	1,067
	2018	1,082
	2019 and thereafter	8,543
	Total	$	13,324

Debt_Tables

Debt (Tables)	9 Months Ended
	Sep. 30, 2014
Debt Disclosure [Abstract]	'
Company's Borrowings	'
	The Company’s debt is as follows:
		30-Sep-14		31-Dec-13
	Convertible debt	$	120,207	$	—
	REG Geismar GOZone bonds	100,000		—
	REG Danville term loan	2,113		5,626
	REG Newton term loan	15,524		18,143
	REG Mason City term loan	4,710		5,135
	Other	5,046		1,247
	Total debt	$	247,600	$	30,151
	Bell, LLC promissory note—variable interest entity	$	—	$	4,029
Revolving Line of Credit	'
	Revolving Line of Credit
		September 30, 2014		December 31, 2013
	Amount borrowed under revolving line of credit	$	—	$	10,986
	Maximum available to be borrowed under revolving line of credit	$	35,975	$	29,014

Related_Party_Transactions_Tab

Related Party Transactions (Tables)	9 Months Ended
	Sep. 30, 2014
Related Party Transactions [Abstract]	'
Summary of Related Party Transactions	'
	Summary of Related Party Balances - Condensed Consolidated Statements of Operations
		Three Months		Three Months		Nine Months		Nine Months
		Ended		Ended		Ended		Ended
		September 30,		September 30,		September 30,		September 30,
		2014		2013		2014		2013
	Cost of goods sold – Biodiesel	$	10,490	$	12,057	$	31,919	$	37,198
	Selling, general and administrative expenses	$	4	$	—	$	43	$	2
	Interest expense	$	1	$	2	$	2	$	30
Summary of Related Party Balances	'
	Summary of Related Party Balances - Condensed Consolidated Balance Sheets
		As of		As of
		September 30, 2014		December 31, 2013
	Accounts receivable	$	141	$	426
	Other assets	$	—	$	35
	Accounts payable	$	570	$	552

Derivative_Instruments_Tables

Derivative Instruments (Tables)	9 Months Ended
	Sep. 30, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Summary of Derivative Financial Instruments by Balance Sheet Location	'
	The following table sets forth the fair value of the Company's commodity contract derivatives and amounts that offset within the Condensed Consolidated Balance Sheets:
		30-Sep-14								31-Dec-13
		Assets				Liabilities				Assets				Liabilities
	Gross amounts of derivatives recognized at fair value	$	11,019			$	210			$	325			$	546
	Cash collateral	3,763				503				13,896				—
	Total gross amount recognized	14,782				713				14,221				546
	Gross amounts offset	(713		)		(713		)		(546		)		(546		)
	Net amount reported in the condensed consolidated balance sheet	$	14,069			$	—			$	13,675			$	—
Summary of Derivative Financial Instruments by Location of Gain (Loss)	'
	The following table sets forth the pre-tax gains (losses) included in the Condensed Consolidated Statements of Operations:
		Location of Gain (Loss)		Three Months				Three Months				Nine Months				Nine Months
		Recognized in income		Ended				Ended				Ended				Ended
				September 30,				September 30,				September 30,				September 30,
				2014				2013				2014				2013
	Commodity derivatives	Cost of goods sold – Biodiesel		$	19,249			$	(11,209	)		$	15,811			$	(3,170	)

Fair_Value_Measurement_Tables

Fair Value Measurement (Tables)	9 Months Ended
	Sep. 30, 2014
Fair Value Disclosures [Abstract]	'
Assets (Liabilities) Measured at Fair Value	'
	A summary of assets (liabilities) measured at fair value is as follows:
		As of September 30, 2014
		Total			Level 1			Level 2			Level 3
	Money market funds	$	561		$	561		$	—		$	—
	Certificates of deposit	11,668			—			11,668			—
	Commercial paper	19,476			—			19,476			—
	Commercial notes/bonds	30,234			—			30,234			—
	Commodity contract derivatives	10,809			3,264			7,545			—
	Contingent consideration for LS9 acquisition	(15,474		)	—			—			(15,474		)
	Contingent consideration for Dynamic Fuels acquisition	(29,033		)	—			—			(29,033		)
		As of December 31, 2013
		Total			Level 1			Level 2			Level 3
	Commodity contract derivatives	$	(221	)	$	—		$	(221	)	$	—
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):
		Contingent Consideration for LS9 Acquisition			Contingent Consideration for Dynamic Fuels Acquisition
	Beginning balance - January 1, 2014	$	—		$	—
	Fair value of contingent liability recorded at measurement date	17,050			—
	Ending balance - March 31, 2014	17,050			—
	Fair value of contingent liability recorded at measurement date	—			28,900
	Change in estimates included in earnings	(384		)	—
	Settlements	—			—
	Ending balance - June 30, 2014	16,666			28,900
	Change in estimates included in earnings	(1,192		)	133
	Settlements	—			—
	Ending balance - September 30, 2014	$	15,474		$	29,033
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 September 30, 2014						As of December 31, 2013
		Asset (Liability)			Fair Value			Asset (Liability)			Fair Value
		Carrying						Carrying
		Amount						Amount
	Financial liabilities:
	Debt and lines of credit	$	(247,600	)	$	(247,915	)	$	(45,166	)	$	(45,094	)

Net_Income_Per_Share_Tables

Net Income Per Share (Tables)	9 Months Ended
	Sep. 30, 2014
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:
		Three Months		Three Months			Nine Months		Nine Months
		Ended		Ended			Ended		Ended
		September 30,		September 30,			September 30,		September 30,
		2014		2013			2014		2013
	Options to purchase common stock	87,026		87,026			87,026		87,026
	Restricted stock units	—		—			—		—
	Stock appreciation rights	1,137,743		314,036			1,401,144		1,194,477
	Warrants to purchase common stock	—		—			17,916		—
	Convertible notes	10,838,218		—			4,764,052		—
	Total	12,062,987		401,062			6,270,138		1,281,503
Calculation of diluted net income per share	'
	The following table presents the calculation of diluted net income per share:
		Three Months			Three Months			Nine Months			Nine Months
		Ended			Ended			Ended			Ended
		September 30,			September 30,			September 30,			September 30,
		2014			2013			2014			2013
	Net income attributable to the Company’s common stockholders - Basic	$	4,504		$	78,462		$	13,362		$	133,958
	Plus: change in undistributed dividends allocated to preferred stockholders	—			147			—			147
	Plus: distributed dividends to Preferred Stockholders	—			258			40			1,848
	Plus (Less): effect of participating securities	—			(355		)	(406		)	(1,992		)
	Net income available to common stockholders - Dilutive	$	4,504		$	78,512		$	12,996		$	133,961
	Shares:
	Weighted-average shares used to compute basic net income per share	42,374,768			33,790,034			40,216,467			31,918,951
	Adjustment to reflect warrants to purchase common stock	17,916			4,533			—			269
	Adjustment to reflect stock appreciation right conversions	39,321			221,909			12,462			4,977
	Weighted-average shares used to compute diluted net income per share	42,432,005			34,016,476			40,228,929			31,924,197
	Net income per share attributable to common stockholders:
	Diluted	$	0.11		$	2.31		$	0.32		$	4.2

Reportable_Segments_Tables

Reportable Segments (Tables)	9 Months Ended
	Sep. 30, 2014
Segment Reporting [Abstract]	'
Segment for the Results of Operations	'
	The following table represents the significant items by reportable segment:
		Three Months			Three Months			Nine Months			Nine Months
		Ended			Ended			Ended			Ended
		September 30,			September 30,			September 30,			September 30,
		2014			2013			2014			2013
	Net revenues:
	Biodiesel	$	384,126		$	458,429		$	935,997		$	1,107,443
	Services	25,422			17,854			72,012			46,809
	Intersegment revenues	(25,290		)	(17,839		)	(71,793		)	(46,705		)
		$	384,258		$	458,444		$	936,216		$	1,107,547
	Income (loss) before income taxes:
	Biodiesel	$	22,603		$	57,854		$	49,278		$	194,770
	Services	112			(5		)	152			(45		)
	Corporate and other (a)	(18,391		)	(13,197		)	(48,484		)	(35,037		)
		$	4,324		$	44,652		$	946		$	159,688
	Depreciation and amortization expense, net:
	Biodiesel	$	3,509		$	2,214		$	8,934		$	5,854
	Services	55			35			148			86
	Corporate and other (a)	335			237			856			669
		$	3,899		$	2,486		$	9,938		$	6,609
	Cash paid for purchases of property, plant and equipment:
	Biodiesel	$	9,749		$	8,363		$	40,655		$	26,573
	Services	12			30			643			504
	Corporate and other (a)	3,508			335			4,281			1,708
		$	13,269		$	8,728		$	45,579		$	28,785
		As of			As of
		September 30, 2014			December 31, 2013
	Assets:
	Biodiesel	$	801,106		$	444,945
	Services	21,036			20,542
	Corporate and other (b)	233,542			275,368
		$	1,055,684		$	740,855
	(a)	Corporate and other includes income/(expense) not associated with the reportable segments, such as corporate general and administrative expenses, shared service expenses, interest expense and interest income.
	(b)	Corporate and other includes cash and other assets not associated with the reportable segments, including investments.

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2014
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.
	October 1, 2014 through December 31, 2014	$	958
	2015	3,857
	2016	3,857
	2017	3,857
	2018	3,784
	2019 and thereafter	19,591
	Total	$	35,904

Basis_of_Presentation_and_Natu1

Basis of Presentation and Nature of the Business (Details)	Sep. 30, 2014
	gal
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Production Capacity Per Year	332,000,000

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Details Textual) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Business Acquisition [Line Items]	'	'	'	'	'
Restricted cash	$104,815	'	$104,815	'	$0
Inventory Adjustments	1,051	'	1,051	'	0
Research and Development Expense	2,810	79	7,900	153	'
Convertible senior notes	143,750	'	143,750	'	'
Dynamic Fuels, LLC	'	'	'	'	'
Business Acquisition [Line Items]	'	'	'	'	'
Restricted cash	101,315	'	101,315	'	'
REG Energy Services	'	'	'	'	'
Business Acquisition [Line Items]	'	'	'	'	'
Restricted cash	3,500	'	3,500	'	'
Syntroleum Corporation and Dynamic Fuels, LLC	'	'	'	'	'
Business Acquisition [Line Items]	'	'	'	'	'
Net deferred tax liability	7,278	'	7,278	'	'
Syntroleum Corporation	'	'	'	'	'
Business Acquisition [Line Items]	'	'	'	'	'
Net operating loss carryforward	$22,600	'	$22,600	'	'
Biodiesel	'	'	'	'	'
Business Acquisition [Line Items]	'	'	'	'	'
Minimum percentage of increase in fair value of goodwill over carrying value	'	'	7.00%	'	'
Services	'	'	'	'	'
Business Acquisition [Line Items]	'	'	'	'	'
Minimum percentage of increase in fair value of goodwill over carrying value	'	'	66.00%	'	'

Acquisitions_and_Equity_Transa2

Acquisitions and Equity Transactions (Details) (USD $)	9 Months Ended		1 Months Ended		0 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Jan. 22, 2014	Sep. 30, 2014	Jun. 03, 2014	Jun. 06, 2014	Sep. 30, 2014	Jun. 06, 2014
			LS9, Inc.	LS9, Inc.	Syntroleum Corporation	Dynamic Fuels, LLC	Syntroleum Corporation and Dynamic Fuels, LLC	Syntroleum Corporation and Dynamic Fuels, LLC
Business Acquisition [Line Items]	'	'	'	'	'	'	'	'
Cash	'	'	$15,275	'	'	$16,447	'	'
Common stock	61,085	'	26,254	'	34,831	'	'	'
Contingent consideration	39,411	0	17,050	15,474	'	28,900	29,033	'
Total	'	'	58,579	'	'	45,347	'	'
Assets (liabilities) acquired:	'	'	'	'	'	'	'	'
Cash	'	'	'	'	'	'	'	253
Other current assets	'	'	'	'	'	'	'	4,666
Property, plant and equipment	'	'	8,215	'	'	'	'	122,827
Goodwill	175,472	84,864	34,846	'	'	'	'	55,762
Intangible assets	'	'	15,956	'	'	'	'	8,900
Other noncurrent assets	'	'	'	'	'	'	'	10,281
Other current liabilities	'	'	'	'	'	'	'	-1,180
Deferred tax liabilities	'	'	'	'	'	'	'	-7,278
Debt	-113,553	'	'	'	'	'	'	-113,553
Other noncurrent liabilities	'	'	-438	'	'	'	'	-500
Total	'	'	$58,579	'	'	'	'	$80,178

Acquisitions_and_Equity_Transa3

Acquisitions and Equity Transactions (Details Textual) (USD $)

3 Months Ended

9 Months Ended

1 Months Ended

3 Months Ended

9 Months Ended

0 Months Ended

9 Months Ended

3 Months Ended

9 Months Ended

0 Months Ended

211 Months Ended

0 Months Ended

In Thousands, except Share data, unless otherwise specified

Sep. 30, 2014

Sep. 30, 2013

Sep. 30, 2014

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2014

Jan. 22, 2014

Sep. 30, 2014

Sep. 30, 2014

Jun. 03, 2014

Sep. 30, 2014

Sep. 30, 2014

Sep. 30, 2014

Jun. 06, 2014

Jul. 25, 2014

Jul. 24, 2014

Jun. 06, 2014

Jun. 03, 2014

gal

gal

Tyson Foods

LS9, Inc.

LS9, Inc.

LS9, Inc.

Syntroleum Corporation

Syntroleum Corporation

Syntroleum Corporation and Dynamic Fuels, LLC

Syntroleum Corporation and Dynamic Fuels, LLC

Syntroleum Corporation and Dynamic Fuels, LLC

416 S. Bell, LLC

416 S. Bell, LLC

Dynamic Fuels, LLC

Dynamic Fuels, LLC

Tyson Foods

Syntroleum Corporation

Syntroleum Corporation

gal

Business Acquisition [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Shares of common stock issued

'

'

'

'

'

'

2,230,559

'

'

3,493,613

'

'

'

'

'

'

'

'

LS9 Earnout Payments

'

'

'

'

'

'

$21,500

'

'

'

'

'

'

'

'

'

'

'

LS9 Earnout Payment, Period

'

'

'

'

'

'

'5 years

'

'

'

'

'

'

'

'

'

'

'

Repayments of Debt

'

'

'

'

'

'

'

'

'

'

'

'

'

13,553

'

'

'

'

Fair Value Inputs, Discount Rate

'

'

'

'

'

'

'

'

8.00%

'

5.80%

'

'

'

'

'

'

'

Net loss

-4,572

-86,703

-13,220

-156,236

'

'

'

3,863

8,527

'

'

-4,766

-9,617

'

'

'

'

'

Equity interest

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

50.00%

50.00%

Production Capacity Per Year

332,000,000

'

332,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

75,000,000

Contingent consideration

39,411

'

39,411

'

0

35,000

17,050

15,474

15,474

'

'

29,033

29,033

'

'

'

'

'

Contingent liability, current

'

'

'

'

'

'

'

'

'

'

'

5,096

5,096

'

'

'

'

'

Revenue

384,258

458,444

936,216

1,107,547

'

'

'

'

'

'

'

262

312

'

'

'

'

'

Income Tax Expense (Benefit)

248

42,051

12,274

-3,452

'

'

'

'

'

'

'

'

3,004

'

'

'

'

'

Noncontrolling Interest, Decrease from Deconsolidation

'

'

'

'

'

'

'

'

'

'

'

'

'

'

50.00%

50.00%

'

'

Cash

'

'

'

'

'

'

$15,275

'

'

'

'

'

'

'

$1,423

'

'

'

Acquisitions_and_Equity_Transa4

Acquisitions and Equity Transactions (Details 1) (Syntroleum Corporation and Dynamic Fuels, LLC, USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Syntroleum Corporation and Dynamic Fuels, LLC	'	'	'	'
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]	'	'	'	'
Revenues	$384,258	$458,463	$936,759	$1,135,692
Net income	$4,504	$67,746	($497)	$131,688
Basic net income (loss) per share	$0.11	$1.77	($0.01)	$3.54

Marketable_Securities_Details

Marketable Securities (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]	'	'
Gross Amortized Cost	$61,396	'
Total Unrealized Gains	7	'
Total Unrealized Losses	-25	'
Fair Value	61,378	0
Commercial paper	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Gross Amortized Cost	19,473	'
Total Unrealized Gains	7	'
Total Unrealized Losses	-4	'
Fair Value	19,476	'
Corporate bonds	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Gross Amortized Cost	30,243	'
Total Unrealized Gains	0	'
Total Unrealized Losses	-9	'
Fair Value	30,234	'
Certificates of deposit	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Gross Amortized Cost	11,680	'
Total Unrealized Gains	0	'
Total Unrealized Losses	-12	'
Fair Value	$11,668	'

Inventories_Details

Inventories (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Inventories	'	'
Raw materials	$22,923	$13,393
Work in process	1,722	1,456
Finished goods	24,737	70,965
Total	$49,382	$85,814

Prepaid_Expenses_and_Other_Ass2

Prepaid Expenses and Other Assets (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Summary of prepaid expense and other assets	'	'
Commodity derivatives and related collateral, net	$14,069	$13,675
Prepaid expenses	5,172	2,414
Deposits	4,314	293
RIN inventory	11,753	6,455
Income taxes receivable	2,028	2,197
Other	2,450	534
Total	$39,786	$25,568

Prepaid_Expenses_and_Other_Ass3

Prepaid Expenses and Other Assets (Details Textual) (USD $)	9 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Other Assets [Abstract]	'	'
Inventory reduced to lower of cost or market	$260	$1,277
Accumulated amortization, debt issuance costs	$1,207	$715

Prepaid_Expenses_and_Other_Ass4

Prepaid Expenses and Other Assets (Other Noncurrent Assets) (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]	'	'
Investments	$10,003	$7,351
Debt issuance costs (net of accumulated amortization of $1,207 and $715, respectively)	4,837	832
Spare parts inventory	3,671	3,671
Deposits	3,870	0
Other	6,975	526
Total	$29,356	$12,380

Goodwill_Details

Goodwill (Details) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014
Goodwill [Roll Forward]	'
Balance	$84,864
Acquisitions	90,608
Balance	175,472
Biodiesel	'
Goodwill [Roll Forward]	'
Balance	68,784
Acquisitions	90,608
Balance	159,392
Services	'
Goodwill [Roll Forward]	'
Balance	16,080
Acquisitions	0
Balance	$16,080

Intangible_Assets_Details

Intangible Assets (Details) (USD $)	9 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]	'	'
Cost, finite-lived	$14,918	$5,702
Accumulated Amortization, finite-lived	-1,594	-835
Total	13,324	4,867
Cost, indefinite lived	30,874	5,702
Accumulated Amortization, indefinite-lived	-1,594	-835
Net, indefinite-lived	29,280	4,867
In-process research and development, indefinite lives	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Cost, indefinite lived	15,956	0
Accumulated Amortization, indefinite-lived	0	0
Net, indefinite-lived	15,956	0
Raw material supply agreement	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Cost, finite-lived	5,818	5,502
Accumulated Amortization, finite-lived	-1,017	-753
Total	4,801	4,749
Weighted Average Remaining Life	'11 years 3 months	'12 years
Renewable hydrocarbon diesel technology	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Cost, finite-lived	8,300	'
Accumulated Amortization, finite-lived	-184	'
Total	8,116	'
Weighted Average Remaining Life	'14 years 9 months	'
Trademarks	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Cost, finite-lived	600	'
Accumulated Amortization, finite-lived	-300	'
Total	300	'
Weighted Average Remaining Life	'0 years 3 months	'
Ground lease	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Cost, finite-lived	200	200
Accumulated Amortization, finite-lived	-93	-82
Total	$107	$118
Weighted Average Remaining Life	'7 years 1 month 24 days	'7 years 10 months 24 days

Intangible_Assets_Details_1

Intangible Assets (Details 1) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Estimated amortization expense	'	'
October 1, 2014 through December 31, 2014	$542	'
2015	1,038	'
2016	1,052	'
2017	1,067	'
2018	1,082	'
2019 and thereafter	8,543	'
Total	$13,324	$4,867

Intangible_Assets_Details_Text

Intangible Assets (Details Textual) (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'	'	'	'
Intangible amortization expense	$583	$89	$760	$236

Debt_Details

Debt (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Company's borrowings	'	'
Total notes payable	$247,600	$30,151
Convertible debt	'	'
Company's borrowings	'	'
Total notes payable	120,207	0
REG Geismar GOZone bonds	'	'
Company's borrowings	'	'
Total notes payable	100,000	0
REG Danville term loan	'	'
Company's borrowings	'	'
Total notes payable	2,113	5,626
REG Newton term loan	'	'
Company's borrowings	'	'
Total notes payable	15,524	18,143
REG Mason City term loan	'	'
Company's borrowings	'	'
Total notes payable	4,710	5,135
Other	'	'
Company's borrowings	'	'
Total notes payable	5,046	1,247
Bell, LLC promissory note—variable interest entity	'	'
Company's borrowings	'	'
Total notes payable	$0	$4,029

Debt_Details_Textual

Debt (Details Textual) (USD $)	0 Months Ended			1 Months Ended	9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Jul. 08, 2014	Sep. 30, 2014	Jul. 08, 2014	Oct. 31, 2008	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2014
	GOZone Bonds	GOZone Bonds	GOZone Bonds	GOZone Bonds	Convertible debt	Convertible debt	Convertible debt	Convertible debt	Debt Instrument, Redemption, Period One	Debt Instrument, Redemption, Period Two
				Subsidiary		Long-term Debt	Stockholders' Equity	Deferred Financing and Equity Costs	Convertible debt	Convertible debt
				Dynamic Fuels, LLC					D	D
Debt Instrument [Line Items]	'	'	'	'	'	'	'	'	'	'
Value of notes issued	'	'	$100,000	'	$143,750	'	'	'	'	'
Interest rate	'	'	'	'	2.75%	'	'	'	'	'
Conversion rate	'	'	'	'	75.3963	'	'	'	'	'
Initial conversion price	'	'	'	'	$13.26	'	'	'	'	'
Threshold Trading Days	'	'	'	'	'	'	'	'	20	5
Consecutive Trading Days	'	'	'	'	'	'	'	'	'30 days	'5 days
Threshold Percentage of Stock Price Trigger	'	'	'	'	'	'	'	'	130.00%	98.00%
Principal conversion basis	'	'	'	'	'	'	'	'	'	1,000
Trading Day Observation Period	'	'	'	'	'80 days	'	'	'	'	'
Percentage of principal amount repurchased	'	'	'	'	100.00%	'	'	'	'	'
Effective interest rate	'	0.04%	'	'	3.80%	'	'	'	'	'
Net proceeds from convertible debt	'	'	'	'	143,750	118,719	25,031	4,563	'	'
Percentage of shares covered by capped call	'	'	'	'	92.50%	'	'	'	'	'
Cap price	'	'	'	'	16.02	'	'	'	'	'
Value of purchased capped calls	'	'	'	'	11,904	'	'	'	'	'
Proceeds from issuance	'	'	'	100,000	'	'	'	'	'	'
Letter of Credit	'	'	101,315	'	'	'	'	'	'	'
Interest	$1,315	'	'	'	'	'	'	'	'	'

Debt_Details_1

Debt (Details 1) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Debt Disclosure [Abstract]	'	'
Amount borrowed under revolving line of credit	$0	$10,986
Maximum available to be borrowed under revolving line of credit	$35,975	$29,014

Related_Party_Transactions_Det

Related Party Transactions (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Summary of Related Party Transactions	'	'	'	'
Cost of goods sold – Biodiesel	$10,490	$12,057	$31,919	$37,198
West Central	'	'	'	'
Summary of Related Party Transactions	'	'	'	'
Cost of goods sold – Biodiesel	10,490	12,057	31,919	37,198
Selling, general and administrative expenses	4	0	43	2
Interest expense	$1	$2	$2	$30

Related_Party_Transactions_Det1

Related Party Transactions (Details 1) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Summary of Related Party Balances	'	'
Accounts receivable	$141	$426
Other assets	0	35
Accounts payable	570	552
West Central	'	'
Summary of Related Party Balances	'	'
Accounts receivable	141	426
Other assets	0	35
Accounts payable	$570	$552

Related_Party_Transactions_Det2

Related Party Transactions (Details Textual) (West Central, USD $)	9 Months Ended
	Sep. 30, 2014
Related Party Transaction [Line Items]	'
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	5.00%
Annual land lease cost	$1
Lease Agreements	'
Related Party Transaction [Line Items]	'
Agreement initial term	'20 years
Additional Lease Period, Number of Extensions	6
Additional renewal period	'5 years
Raw material supply agreement	'
Related Party Transaction [Line Items]	'
Additional renewal period	'1 year
Delivery Requirement Period	'45 days
Accounts payable, amounts owed to related parties	$3,000,000

Derivative_Instruments_Details

Derivative Instruments (Details Textual)	Sep. 30, 2014
	Contract
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Open commodity contracts	2,255

Derivative_Instruments_Details1

Derivative Instruments (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Assets	'	'
Gross amounts of derivatives recognized at fair value	$11,019	$325
Cash collateral	3,763	13,896
Total gross amount recognized	14,782	14,221
Gross amounts offset	-713	-546
Net amount reported in the condensed consolidated balance sheet	14,069	13,675
Liabilities	'	'
Gross amounts of derivatives recognized at fair value	210	546
Cash collateral	503	0
Total gross amount recognized	713	546
Gross amounts offset	-713	-546
Net amount reported in the condensed consolidated balance sheet	$0	$0

Derivative_Instruments_Details2

Derivative Instruments (Details 1) (Cost of goods sold – Biodiesel, Commodity derivatives, USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Cost of goods sold – Biodiesel | Commodity derivatives	'	'	'	'
Derivative Instruments Gain Loss [Line Items]	'	'	'	'
Pre-tax gains (losses) included in the condensed consolidated statement of operations	$19,249	($11,209)	$15,811	($3,170)

Fair_Value_Measurement_Details

Fair Value Measurement (Details) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Commodity contract derivatives	'	'
Assets (liabilities) measured at fair value	'	'
Liabilities, fair value	($10,809)	($221)
Commodity contract derivatives | Level 1	'	'
Assets (liabilities) measured at fair value	'	'
Liabilities, fair value	-3,264	0
Commodity contract derivatives | Level 2	'	'
Assets (liabilities) measured at fair value	'	'
Liabilities, fair value	-7,545	-221
Commodity contract derivatives | Level 3	'	'
Assets (liabilities) measured at fair value	'	'
Liabilities, fair value	0	0
Contingent consideration for acquisition | LS9, Inc.	'	'
Assets (liabilities) measured at fair value	'	'
Liabilities, fair value	-15,474	'
Contingent consideration for acquisition | LS9, Inc. | Level 1	'	'
Assets (liabilities) measured at fair value	'	'
Liabilities, fair value	0	'
Contingent consideration for acquisition | LS9, Inc. | Level 2	'	'
Assets (liabilities) measured at fair value	'	'
Liabilities, fair value	0	'
Contingent consideration for acquisition | LS9, Inc. | Level 3	'	'
Assets (liabilities) measured at fair value	'	'
Liabilities, fair value	-15,474	'
Contingent consideration for acquisition | Dynamic Fuels, LLC	'	'
Assets (liabilities) measured at fair value	'	'
Liabilities, fair value	-29,033	'
Contingent consideration for acquisition | Dynamic Fuels, LLC | Level 1	'	'
Assets (liabilities) measured at fair value	'	'
Liabilities, fair value	0	'
Contingent consideration for acquisition | Dynamic Fuels, LLC | Level 2	'	'
Assets (liabilities) measured at fair value	'	'
Liabilities, fair value	0	'
Contingent consideration for acquisition | Dynamic Fuels, LLC | Level 3	'	'
Assets (liabilities) measured at fair value	'	'
Liabilities, fair value	-29,033	'
Money market funds	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	561	'
Money market funds | Level 1	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	561	'
Money market funds | Level 2	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	0	'
Money market funds | Level 3	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	0	'
Certificates of deposit	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	11,668	'
Certificates of deposit | Level 1	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	0	'
Certificates of deposit | Level 2	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	11,668	'
Certificates of deposit | Level 3	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	0	'
Commercial paper	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	19,476	'
Commercial paper | Level 1	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	0	'
Commercial paper | Level 2	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	19,476	'
Commercial paper | Level 3	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	0	'
Commercial notes/bonds	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	30,234	'
Commercial notes/bonds | Level 1	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	0	'
Commercial notes/bonds | Level 2	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	30,234	'
Commercial notes/bonds | Level 3	'	'
Assets (liabilities) measured at fair value	'	'
Assets, fair value	$0	'

Fair_Value_Measurement_Details1

Fair Value Measurement (Details 1) (Contingent Consideration for Acquisition, USD $)	3 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014
LS9, Inc.	'	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'
Beginning balance	$16,666	$17,050	$0
Fair value of contingent liability recorded at measurement date	'	0	17,050
Change in estimates included in earnings	-1,192	-384	'
Settlements	0	0	'
Ending balance	15,474	16,666	17,050
Dynamic Fuels, LLC	'	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'
Beginning balance	28,900	0	0
Fair value of contingent liability recorded at measurement date	'	28,900	0
Change in estimates included in earnings	133	0	'
Settlements	0	0	'
Ending balance	$29,033	$28,900	$0

Fair_Value_Measurement_Details2

Fair Value Measurement (Details 2) (USD $)	Sep. 30, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Asset (Liability) Carrying Amount	'	'
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]	'	'
Debt and lines of credit	($247,600)	($45,166)
Fair Value	'	'
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]	'	'
Debt and lines of credit	($247,915)	($45,094)

Fair_Value_Measurement_Details3

Fair Value Measurement (Details Textual)	9 Months Ended
	Sep. 30, 2014
LS9, Inc.	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'
Fair Value Inputs, Discount Rate	8.00%
Dynamic Fuels, LLC	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'
Fair Value Inputs, Discount Rate	5.80%

Net_Income_Per_Share_Details

Net Income Per Share (Details)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Total	12,062,987	401,062	6,270,138	1,281,503
Options to purchase common stock	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Total	87,026	87,026	87,026	87,026
Warrants to purchase common stock	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Total	0	0	17,916	0
Convertible notes	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Total	10,838,218	0	4,764,052	0
Restricted stock units	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Total	0	0	0	0
Stock appreciation rights	'	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'	'
Total	1,137,743	314,036	1,401,144	1,194,477

Net_Income_Per_Share_Details_1

Net Income Per Share (Details 1) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Earnings Per Share [Abstract]	'	'	'	'
NET INCOME ATTRIBUTABLE TO THE COMPANY’S COMMON STOCKHOLDERS	$4,504	$78,462	$13,362	$133,958
Plus: change in undistributed dividends allocated to preferred stockholders	0	147	0	147
Plus: distributed dividends to Preferred Stockholders	0	258	40	1,848
Plus (Less): effect of participating securities	0	-355	-406	-1,992
Net income available to common stockholders - Dilutive	$4,504	$78,512	$12,996	$133,961
Weighted-average shares used to compute basic net income per share	42,374,768	33,790,034	40,216,467	31,918,951
Adjustment to reflect warrants to purchase common stock	17,916	4,533	0	269
Adjustment to reflect stock appreciation right conversions	39,321	221,909	12,462	4,977
Weighted-average shares used to compute diluted net income per share	42,432,005	34,016,476	40,228,929	31,924,197
Diluted	$0.11	$2.31	$0.32	$4.20

Reportable_Segments_Details

Reportable Segments (Details) (USD $)	3 Months Ended				9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013		Dec. 31, 2013
Segment Reporting Information [Line Items]	'		'		'		'		'
Net revenues:	$384,258		$458,444		$936,216		$1,107,547		'
Income (loss) before income taxes:	4,324		44,652		946		159,688		'
Depreciation and amortization expense, net:	3,899		2,486		9,938		6,609		'
Cash paid for purchases of property, plant and equipment:	13,269		8,728		45,579		28,785		'
Assets:	1,055,684		'		1,055,684		'		740,855
Intersegment revenues	'		'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'		'
Net revenues:	-25,290		-17,839		-71,793		-46,705		'
Corporate and other	'		'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'		'
Income (loss) before income taxes:	-18,391	[1]	-13,197	[1]	-48,484	[1]	-35,037	[1]	'
Depreciation and amortization expense, net:	335	[1]	237	[1]	856	[1]	669	[1]	'
Cash paid for purchases of property, plant and equipment:	3,508	[1]	335	[1]	4,281	[1]	1,708	[1]	'
Assets:	233,542	[2]	'		233,542	[2]	'		275,368	[2]
Biodiesel | Segments	'		'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'		'
Net revenues:	384,126		458,429		935,997		1,107,443		'
Income (loss) before income taxes:	22,603		57,854		49,278		194,770		'
Depreciation and amortization expense, net:	3,509		2,214		8,934		5,854		'
Cash paid for purchases of property, plant and equipment:	9,749		8,363		40,655		26,573		'
Assets:	801,106		'		801,106		'		444,945
Services | Segments	'		'		'		'		'
Segment Reporting Information [Line Items]	'		'		'		'		'
Net revenues:	25,422		17,854		72,012		46,809		'
Income (loss) before income taxes:	112		-5		152		-45		'
Depreciation and amortization expense, net:	55		35		148		86		'
Cash paid for purchases of property, plant and equipment:	12		30		643		504		'
Assets:	$21,036		'		$21,036		'		$20,542
[1]	Corporate and other includes income/(expense) not associated with the reportable segments, such as corporate general and administrative expenses, shared service expenses, interest expense and interest income.
[2]	Corporate and other includes cash and other assets not associated with the reportable segments, including investments.

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (USD $)	Sep. 30, 2014
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]	'
October 1, 2014 through December 31, 2014	$958
2015	3,857
2016	3,857
2017	3,857
2018	3,784
2019 and thereafter	19,591
Total	$35,904