Investment in Unconsolidated Subsidiary Selected Financial Information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Assets:
Property, plant and equipment, net	$ 373,117	$ 382,011
Total assets	592,200	488,435
Liabilities and members' equity:
Total current portion of long term debt	57,514	8,511
Total long term debt	155,273	212,787
Total members' equity	357,761	230,228
Expenses:
Operating income	145,091	24,336	(5,324)
Interest and debt expense, net	(17,640)	(9,049)	0
Diamond Green Diesel Holdings LLC Joint Venture [Member]
Assets:
Total current assets	216,991	106,332
Other assets	2,092	92
Liabilities and members' equity:
Total other current liabilities	21,313	36,702
Total other long term liabilities	339	207
Total liabilities and member's equity	592,200	488,435
Revenues:
Operating revenues	487,834	213,552	0
Expenses:
Total costs and expenses	342,743	189,216	5,324
Other income	82	33	0
Net income/(loss)	$ 127,533	$ 15,320	$ (5,324)