Investment in Unconsolidated Subsidiary (Assets, Liabilities and members' equity) (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
ASSETS
Property, plant and equipment, net	$ 355,809	$ 356,230
Total assets	548,661	620,708
Liabilities and members' equity:
Total current portion of long term debt	17,023	62,023
Total long term debt	68,564	86,819
Total liabilities and member's equity	439,889	451,551
Diamond Green Diesel Holdings LLC Joint Venture [Member]
ASSETS
Total current assets	175,782	261,444
Other assets	17,070	3,034
Liabilities and members' equity:
Total other current liabilities	22,785	19,935
Total other long term liabilities	400	380
Equity Method Investment, Summarized Financial Information, Liabilities and Equity	$ 548,661	$ 620,708