Income Taxes - Components of Income Tax Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
Federal	$ 284,199	$ 309,403	$ 224,591
State	41,083	45,460	43,513
Foreign	28,593	27,602	84,030
Deferred	33,226	35,544	54,319
Income tax expense, total	$ 387,100	$ 418,009	$ 406,453