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Noncontrolling Interests in Subsidiaries (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling interests in subsidiaries	$ 126,603		$ 126,603		$ 120,119
Net Income (Loss)	(50,933)	$ (8,501)	(71,457)	$ (26,402)
Net Income (Loss) Attributable to Noncontrolling Interest	$ 4,226	$ (9,188)	$ 10,888	(7,520)
Illinois Corn Processing LLC [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling interests in subsidiaries					22,272
Offshore Marine Services [Member] \| Windcat Workboats Ltd. [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	25.00%		25.00%
Noncontrolling interests in subsidiaries	$ 5,956		$ 5,956		7,484
Assets, Net	23,800		23,800
Net Income (Loss)			(3,300)	3,600
Net Income (Loss) Attributable to Noncontrolling Interest			(800)
Offshore Marine Services [Member] \| Other Offshore Marine Services Noncontrolling Interests [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling interests in subsidiaries	263		263		470
Inland River Services [Member] \| Other Inland River Services Noncontrolling Interests [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling interests in subsidiaries	$ 951		$ 951		1,146
Shipping Services [Member] \| Sea-Vista [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	49.00%		49.00%
Noncontrolling interests in subsidiaries	$ 98,906		$ 98,906		88,290
Assets, Net	$ 201,800		201,800
Net Income (Loss)			$ 21,700	(25,900)
Illinois Corn Processing LLC [Member] \| Illinois Corn Processing LLC [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	30.00%		30.00%
Noncontrolling interests in subsidiaries	$ 20,374		$ 20,374
Assets, Net	67,900		67,900
Net Income (Loss)			4,700	14,600
Net Income (Loss) Attributable to Noncontrolling Interest			1,400	$ 4,400
Other Segments [Member] \| Other Noncontrolling Interests [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling interests in subsidiaries	$ 153		$ 153		$ 457
Minimum [Member] \| Offshore Marine Services [Member] \| Other Offshore Marine Services Noncontrolling Interests [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	1.80%		1.80%
Minimum [Member] \| Inland River Services [Member] \| Other Inland River Services Noncontrolling Interests [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	3.00%		3.00%
Minimum [Member] \| Other Segments [Member] \| Other Noncontrolling Interests [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	5.00%		5.00%
Maximum [Member] \| Offshore Marine Services [Member] \| Other Offshore Marine Services Noncontrolling Interests [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	30.00%		30.00%
Maximum [Member] \| Inland River Services [Member] \| Other Inland River Services Noncontrolling Interests [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	51.80%		51.80%
Maximum [Member] \| Other Segments [Member] \| Other Noncontrolling Interests [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	14.60%		14.60%