Income Taxes - Components of Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current expense:
Federal	$ 58,816	$ 38,831	$ 68,142
State	1,173	363	7,538
Foreign	10,364	7,124	3,752
Total current income tax expense	70,353	46,318	79,432
Deferred (benefit) expense:
Federal	(22,951)	(18,755)	(34,479)
State	25	(610)	2,698
Foreign	(9,222)	209	918
Total deferred income tax expense	(32,148)	(19,156)	(30,863)
Total income tax expense (benefit)	$ 38,205	$ 27,162	$ 48,569