Acquisitions (Details Textual) $ in Thousands, gal in Millions	Mar. 15, 2016 USD ($) shares gal	Mar. 31, 2016 USD ($) gal	Dec. 31, 2015 USD ($)
Business Acquisition [Line Items]
Production capacity per year | gal		452
Contingent consideration for acquisitions		$ 28,890	$ 26,949
Sanimax Energy, LLC
Business Acquisition [Line Items]
Production capacity per year | gal	20	20
Shares of common stock issued | shares	500,000
Contingent consideration for acquisitions	$ 5,000	$ 4,500
Earnout payment period	7 years
Maximum Earnout Payment per year	$ 1,700
Current contingent liability		$ 1,231