Income Taxes - Components of Deferred Taxes (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred Tax Assets:
Accrued third party obligations, deductible for taxes upon economic performance	$ 14,473	$ 17,769
Provision for doubtful accounts receivable	1,041	957
Excess of financial statement over tax depreciation	10,349	10,905
Deductible stock compensation expense, net	18,910	15,122
Foreign currency translation adjustment	44,519	20,719
Retained liability for cargo claims	1,350	1,555
Total gross deferred tax assets	90,642	67,027
Deferred Tax Liabilities:
Unremitted foreign earnings, net of related foreign tax credits	(100,170)	(82,262)
Total gross deferred tax liabilities	(100,170)	(82,262)
Net deferred tax liabilities	(9,528)	(15,235)
Current deferred tax assets	(16,861)	(20,279)
Noncurrent deferred tax liabilities	$ 26,389	$ 35,514