Revenues - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Jan. 01, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	$ 22,462
Deferred contract costs	120,861			$ 0
Contract liabilities	147,236			$ 0
Revenue from Contract with Customer, Excluding Assessed Tax	1,854,262	$ 1,545,132
Cost of Customs brokerage and other services	1,661,444	1,399,018
Customs brokerage and other services
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	602,152	$ 435,828
Prospective Change in Presentation Gross vs. Net | Customs brokerage and other services
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	50,000
Cost of Customs brokerage and other services	$ 50,000
Revenue Accounting Standards Update
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets			$ 22,462
Deferred contract costs			135,000
Contract liabilities			$ 165,000