The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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Aggregate notional amount of foreign currency exchange rate derivatives. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

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Derivative Financial Instruments (Details)	3 Months Ended		6 Months Ended						6 Months Ended
Derivative Financial Instruments (Details)	Jun. 30, 2011 USD ($)	Jun. 30, 2010 USD ($)	Jun. 30, 2011 USD ($)	Jun. 30, 2010 USD ($)	Dec. 31, 2010 USD ($)	Dec. 01, 2010 USD ($)	Dec. 01, 2010 AUD	Oct. 02, 2008 USD ($)	Jun. 30, 2011 AUD BBSW Interest Rate [Member] Cross-currency swap [Member]	Jun. 30, 2011 Libor Interest Rate [Member] Cross-currency swap [Member]	Dec. 01, 2010 FreightLink [Member] USD ($)	Dec. 01, 2010 FreightLink [Member] AUD	Jun. 30, 2011 Cross-currency swap [Member] Fair Value, Inputs, Level 2 [Member] USD ($)
Derivatives [Line Items]
Notional Amount of Interest Rate Derivatives								$ 120,000,000
Derivative, Fixed Interest Rate								3.88%
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net			0
Third-party debt associated with foreign currency debt	160,500,000		160,500,000
Acquisition of assets											320,019,000	331,936,000
Notional Amount of Foreign Currency Derivatives						100,600,000	105,000,000
Derivative, Description of Variable Rate Basis									Australian dollar BBSW plus 3.125%	LIBOR plus 2.48%
Other income/(expense)	170,000	(175,000)	469,000	275,000
Derivative liability	$ 21,277,000		$ 21,277,000		$ 16,751,000								$ 12,855,000