Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Provisional income tax expense (benefit)	$ 50,986
Deferred tax asset, provisional income tax expense	13,854
Accumulated foreign earnings, provisional liability	37,132
Transition tax for accumulated foreign earnings, provisional income tax expense	37,132
Operating loss carryforwards	111,006
Operating loss carryforwards, not subject to expiration	94,579
Operating loss carryforwards, subject to expiration	16,427
Unrecognized tax benefits including interest and penalties	16,919	$ 17,176
Unrecognized tax benefits that would impact effective tax rate	10,847	9,615
Interest and penalties paid by the Company	(3,384)	5	$ 1,051
Accrued interest and penalties	$ 2,151	$ 1,848