Goodwill and Intangible Assets - Finite Lived Intangible Assets Amortization Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Goodwill And Intangible Assets Disclosure [Abstract]
Intangible assets - finite life, Beginning of period			$ 60,728	$ 74,957
Amortization expense	$ (2,900)	$ (3,700)	(5,772)	(7,645)
Foreign currency adjustments			493	76
Intangible assets - finite life, End of period	$ 55,449	$ 67,388	$ 55,449	$ 67,388