Revenue from Contracts with Customers - Changes in Deferred Revenue (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Movement in Deferred Revenue [Roll Forward]
Beginning balance	$ 365,274	$ 343,174
Acquired deferred revenue	1,405	3,266
Deferral of revenue	661,790	675,209
Recognition of revenue	(690,646)	(685,765)
Currency translation	(1,635)	(500)
Ending balance	$ 336,188	$ 335,384