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