Fair Value Measurements (Details 1) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands		Dec. 31, 2016	Dec. 31, 2015
Assets and liabilities measured at fair value on a recurring basis
Cash equivalents		$ 0	$ 26,931
Restricted cash		471	450
Commodity derivatives, net	[1]	22,041	11,789
Provisionally priced contracts	[2]	(170,197)	(236,990)
Convertible preferred securities	[3]	3,294	13,550
Other assets and liabilities	[4]	6,861	5,661
Total		(137,530)	(178,609)
Level 1
Assets and liabilities measured at fair value on a recurring basis
Cash equivalents		0	26,931
Restricted cash		471	450
Commodity derivatives, net	[1]	29,872	26,890
Provisionally priced contracts	[2]	(105,321)	(133,842)
Convertible preferred securities	[3]	0	0
Other assets and liabilities	[4]	9,391	8,635
Total		(65,587)	(70,936)
Level 2
Assets and liabilities measured at fair value on a recurring basis
Cash equivalents		0	0
Restricted cash		0	0
Commodity derivatives, net	[1]	(7,831)	(15,101)
Provisionally priced contracts	[2]	(64,876)	(103,148)
Convertible preferred securities	[3]	0	0
Other assets and liabilities	[4]	(2,530)	(3,324)
Total		(75,237)	(121,573)
Level 3
Assets and liabilities measured at fair value on a recurring basis
Cash equivalents		0	0
Restricted cash		0	0
Commodity derivatives, net	[1]	0	0
Provisionally priced contracts	[2]	0	0
Convertible preferred securities	[3]	3,294	13,550
Other assets and liabilities	[4]	0	350
Total		$ 3,294	$ 13,900

[1] Includes associated cash posted/received as collateral

[2] Included in "Provisionally priced contracts" are those instruments based only on underlying futures values (Level 1) and delayed price contracts (Level 2)

[3] Recorded in “Other noncurrent assets” on the Company’s Consolidated Balance Sheets

[4] Included in other assets and liabilities are deferred compensation assets, ethanol risk management contracts, and foreign exchange derivative contracts (Level 1), interest rate derivatives (Level 2), and contingent consideration to the former owners of Kay Flo Industries, Inc (Level 3)