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Noncontrolling Interests in Subsidiaries (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling interests in subsidiaries	$ 132,224		$ 132,224		$ 120,119
Net Income (Loss)	(34,026)	$ 16,405	(105,483)	$ (9,997)
Net Income (Loss) Attributable to Noncontrolling Interest	$ 5,777	$ 9,440	$ 16,665	1,920
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	$ 5,730		$ 5,730		7,484
Assets, Net	22,900		22,900
Net Income (Loss)			(3,600)	3,400
Net Income (Loss) Attributable to Noncontrolling Interest			(900)
Offshore Marine Services [Member] \| Other Offshore Marine Services Noncontrolling Interests [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling interests in subsidiaries	265		265		470
Inland River Services [Member] \| Other Inland River Services Noncontrolling Interests [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling interests in subsidiaries	$ 953		$ 953		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	$ 104,182		$ 104,182		88,290
Assets, Net	$ 212,600		212,600
Net Income (Loss)			$ 32,400	(9,600)
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	$ 20,942		$ 20,942
Assets, Net	69,800		69,800
Net Income (Loss)			6,600	19,400
Net Income (Loss) Attributable to Noncontrolling Interest			2,000	$ 5,800
Other Segments [Member] \| Other Noncontrolling Interests [Member]
Noncontrolling Interests in Subsidiaries [Line Items]
Noncontrolling interests in subsidiaries	$ 152		$ 152		$ 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%