Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Costs and Expenses [Abstract]
Total costs and expenses	$ 148,290	$ 103,368	$ 375,794	$ 304,609
Gains (Losses) on Asset Dispositions and Impairments, Net	5,209	(593)	10,918	2,590
Net Income (Loss)	0	(25,392)	(23,150)	(62,809)
Offshore Marine Services [Member]
Operating Revenues	0	54,125	62,291	171,275
Costs and Expenses [Abstract]
Operating	0	41,159	65,888	134,254
Administrative and general	0	10,588	29,682	34,915
Depreciation and amortization	0	14,213	22,181	44,305
Total costs and expenses	0	65,960	117,751	213,474
Operating Income (Loss)	0	(41,068)	(51,241)	(92,169)
Other Income (Expense), Net	0	(2,993)	1,780	(14,675)
Income Tax Expense (Benefit)	0	(15,263)	(12,931)	(35,831)
Equity in Earnings (Losses) of 50% or Less Owned Companies	0	790	1,663	(364)
Net Income (Loss)	0	(28,008)	(34,867)	(71,377)
Net Income (Loss) Attributable to Noncontrolling Interests	0	(73)	(1,892)	(904)
Illinois Corn Processing LLC [Member]
Operating Revenues	0	44,019	78,061	134,204
Costs and Expenses [Abstract]
Operating	0	39,879	76,306	122,321
Administrative and general	0	750	2,109	2,318
Depreciation and amortization	0	1,055	2,354	3,172
Total costs and expenses	0	41,684	80,769	127,811
Operating Income (Loss)	0	2,335	(2,708)	6,393
Other Income (Expense), Net	18,223	537	20,558	3,014
Income Tax Expense (Benefit)	7,296	921	7,363	2,903
Net Income (Loss)	10,927	1,951	10,487	6,504
Net Income (Loss) Attributable to Noncontrolling Interests	0	569	(539)	1,975
Intersegment Eliminations [Member]
Operating Revenues	0	(731)	(1,176)	(1,799)
Costs and Expenses [Abstract]
Operating	0	(815)	(1,289)	(2,065)
Administrative and general	0	(24)	(42)	(77)
Total costs and expenses	0	(839)	(1,331)	(2,142)
Operating Income (Loss)	0	108	155	343
Other Income (Expense), Net	0	916	1,738	2,833
Income Tax Expense (Benefit)	0	359	663	1,112
Net Income (Loss)	0	665	1,230	2,064
Offshore Marine Services [Member] | Offshore Marine Services [Member]
Costs and Expenses [Abstract]
Gains (Losses) on Asset Dispositions and Impairments, Net	$ 0	$ (29,233)	$ 4,219	$ (49,970)