Fair Value Measurements (Non-Financial Assets And Liabilities Measured At Fair Value) (Details) (USD $)	9 Months Ended
	Sep. 30, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Decrease in other current liabilities	$ 200,000
Number of helicopters leased	3
Maximum percentage of investment held	50.00%
Level 1 [Member] | Avion Logistics Limited [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in affiliates (included in Investments, at Equity, and Advances to 50% or Less Owned Companies)		[1]
Level 2 [Member] | Avion Logistics Limited [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in affiliates (included in Investments, at Equity, and Advances to 50% or Less Owned Companies)	1,000,000	[1]
Level 3 [Member] | Avion Logistics Limited [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in affiliates (included in Investments, at Equity, and Advances to 50% or Less Owned Companies)		[1]
Avion Logistics Limited [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Maximum percentage of investment held	50.00%
Level 1 [Member] | Soylutions LLC [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in affiliates (included in Investments, at Equity, and Advances to 50% or Less Owned Companies)		[1]
Level 2 [Member] | Soylutions LLC [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in affiliates (included in Investments, at Equity, and Advances to 50% or Less Owned Companies)	11,992,000	[1]
Level 3 [Member] | Soylutions LLC [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in affiliates (included in Investments, at Equity, and Advances to 50% or Less Owned Companies)		[1]
Soylutions LLC [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Maximum percentage of investment held	50.00%
Level 1 [Member] | Mantenimiento Express Maritimo, S.A.P.I. De C.V. [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in affiliates (included in Investments, at Equity, and Advances to 50% or Less Owned Companies)		[2]
Level 2 [Member] | Mantenimiento Express Maritimo, S.A.P.I. De C.V. [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in affiliates (included in Investments, at Equity, and Advances to 50% or Less Owned Companies)	16,415,000	[2]
Level 3 [Member] | Mantenimiento Express Maritimo, S.A.P.I. De C.V. [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment in affiliates (included in Investments, at Equity, and Advances to 50% or Less Owned Companies)		[2]
Mantenimiento Express Maritimo, S.A.P.I. De C.V. [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Maximum percentage of investment held	50.00%
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Lease Obligations for Helicopters (included in other current liabilities)		[3]
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Lease Obligations for Helicopters (included in other current liabilities)		[3]
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Lease Obligations for Helicopters (included in other current liabilities)	$ 395,000	[3]

[1] During the nine months ended September 30, 2011, the Company marked its investment in its Avion Logistics Limited joint venture and its investment in its Soylutions LLC joint venture to fair value following the acquisition of controlling interests (see Note 6). The investments' fair values were determined based on the Company's purchase prices of the acquired interests.

[2] During the nine months ended September 30, 2011, the Company marked its investment in its Mantenimiento Express Maritimo S.A.P.I. de C.V. joint venture to fair value following the joint venture's sale of an additional equity interest to an unrelated third party (see Note 6). The investment's fair value was determined based on the third party's purchase price of the acquired interest.

[3] During the nine months ended September 30, 2011, the Company recorded a gain of $0.2 million to decrease the carrying value of its exit obligations for three leased-in helicopters.