Segments and Geographic Areas - Reconciliation of Revenue to Adjusted Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting [Abstract]
Revenue	$ 254,149	$ 229,844	$ 242,603	$ 223,198	$ 242,935	$ 231,936	$ 231,964	$ 221,599	$ 949,794	$ 928,434	$ 908,974
Impact of the deferred revenue fair value adjustment									13,077	3,489	6,006
Adjusted revenue									$ 962,871	$ 931,923	$ 914,980