Goodwill and Other Intangible Assets - Schedule of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Goodwill Roll Forward
Goodwill, beginning balance	$ 657,671	$ 650,778
Additions	23,191	25,050
Foreign currency translation and other adjustments	(67,527)	(18,157)
Goodwill, ending balance	$ 613,335	$ 657,671