Disclosures About Fair Value (Details) Gain (Loss) Recognized in Income on Derivative (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives			$ 1,274
Cost of canola oil and meal sold
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives	(5,122)	(2,752)	2,101
Futures | Cost of canola oil and meal sold
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives	(1,693)	(1,339)	(3,469)
Futures | Other income
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives	(1,966)
Futures | Operating and other costs
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives			(708)	[1]
Forwards | Cost of canola oil and meal sold
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives	(391)	(130)	1,637
Forwards | Operating and other costs
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives			98	[1]
Swaps | Cost of canola oil and meal sold
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives	(3,038)	(1,283)	3,933
Swaps | Operating and other costs
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) on derivatives			$ 1,884	[1]

[1] Represents the activity pre-completion of the Company’s canola processing plant.