Income Taxes - Reconciliation of Beginning and Ending Amount of Unrecognized Tax benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Balance of unrecognized tax benefits at beginning of year	$ 21,079	$ 14,780	$ 14,996
Increases for tax positions of prior years	58	1,449	84
Decreases for tax positions of prior years	(361)	(47)	(412)
Increases for tax positions established for the current period	5,185	9,866	491
Decreases for settlements with taxing authorities	(167)	(594)
Reductions resulting from lapse of applicable statute of limitation	(1,310)	(4,218)	(239)
Adjustment resulting from foreign currency translation	(206)	(157)	(140)
Balance of unrecognized tax benefits at end of year	$ 24,278	$ 21,079	$ 14,780