Subsequent Event (Notes)	6 Months Ended
Jun. 30, 2019
Subsequent Events [Abstract]
Subsequent Events [Text Block]	SUBSEQUENT EVENTOn July 24, 2019, the Company announced the closure of its New Boston, Texas biorefinery, REG New Boston, LLC, ("REG New Boston"). REG New Boston's nameplate capacity is 15 mmgy and its closure will reduce the Company's nameplate capacity from 520 mmgy to 505 mmgy. At June 30, 2019, the net book value of REG New Boston's property, plant and equipment was $15,755.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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