Business Segment Information Business Segment Information - Net Revenues Calculation (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Net Revenues Calculation [Line Items]
Total revenues	$ 1,768,830	$ 1,705,105	$ 1,599,141	$ 1,491,645	$ 1,625,859	$ 1,537,966	$ 1,503,224	$ 1,413,208	$ 6,564,721		$ 6,080,257		$ 5,992,215
Airfreight services									2,103,777		1,994,374		1,983,696
Ocean freight and ocean services									1,712,795		1,521,340		1,542,170
Customs brokerage and other services									766,722		681,690		630,979
Net revenues	$ 518,871	$ 513,256	$ 484,714	$ 464,586	$ 478,072	$ 484,902	$ 471,872	$ 448,007	$ 1,981,427	[1]	$ 1,882,853	[1]	$ 1,835,370	[1]

[1] Net revenues are a non-GAAP measure calculated as revenues less directly related operations expenses attributable to the Company's principal services. The Company's management believes that net revenues are a better measure than total revenues when evaluating the Company's operating segment performance since total revenues earned as a freight consolidator include the carriers' charges for carrying the shipment, whereas revenues earned in other capacities include primarily the commissions and fees earned by the Company. Net revenue is one of the Company's primary operational and financial measures and demonstrates the Company's ability to concentrate and leverage purchasing power through effective consolidation of shipments from customers utilizing a variety of transportation carriers and optimal routings.