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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

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-Section A

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-Name Accounting Standards Codification

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Gain (loss) after tax expense or benefit, not previously recognized and resulting from the sale of a business component, which is recognized at the date of sale. A gain (loss) reflects the amount by which the consideration received exceeds (is exceeded by) the net carrying amount (reflecting previous provisions for loss on disposal, if any) of the disposal group.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The amount of net income or loss derived from discontinued operations during the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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-Name Emerging Issues Task Force (EITF)

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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-Name Statement of Financial Accounting Standard (FAS)

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-Name Accounting Standards Codification

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Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

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-Name Regulation S-X (SX)

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Basis of Presentation and Accounting Policy (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended				3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Dec. 31, 2010	Sep. 30, 2012 Offshore Marine Services [Member]	Sep. 30, 2011 Offshore Marine Services [Member]	Sep. 30, 2012 Offshore Marine Services [Member]	Sep. 30, 2011 Offshore Marine Services [Member]	Sep. 30, 2012 Aviation Services [Member]	Sep. 30, 2011 Aviation Services [Member]	Sep. 30, 2012 Aviation Services [Member]	Sep. 30, 2011 Aviation Services [Member]	Sep. 30, 2012 Commodity Trading And Logistics [Member]	Sep. 30, 2011 Commodity Trading And Logistics [Member]	Jun. 30, 2011 Commodity Trading And Logistics [Member]	Sep. 30, 2012 Commodity Trading And Logistics [Member]	Sep. 30, 2011 Commodity Trading And Logistics [Member]	Sep. 30, 2012 Certain Companies and Assets of Environmental Services Segment [Member]	Sep. 30, 2011 Certain Companies and Assets of Environmental Services Segment [Member]	Sep. 30, 2012 Aeroleo [Member] Aviation Services [Member]	Sep. 30, 2012 Customer [Member] Offshore Marine Services [Member]	Sep. 30, 2012 Customer [Member] Aviation Services [Member]
Nature of Operations and Accounting Policies [Line Items]
Proceeds from Divestiture of Businesses																				$ 99,900,000
Gain (Loss) on Disposal of Discontinued Operation, Net of Tax																				20,800,000
Income (Loss) from Discontinued Operations, Net of Tax, Per Diluted Share	$ 0.00	$ (0.03)	$ 0.91	$ (0.10)																$ 1.00
Deferred Revenue	16,787,000	14,234,000	16,787,000	14,234,000	9,968,000	21,045,000																7,700,000	5,600,000	3,400,000
Operating Revenues	$ 462,058,000	$ 545,089,000	$ 1,454,365,000	$ 1,492,383,000			$ 134,322,000	$ 93,277,000	$ 378,684,000	$ 267,007,000	$ 77,989,000	$ 71,804,000	$ 202,026,000	$ 196,452,000	$ 145,725,000	$ 279,178,000	$ 27,900,000	$ 562,166,000	$ 718,511,000	$ 22,400,000	$ 87,800,000