Share-Based Awards - Effects of Share Based Compensation in Consolidated Statements of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation	$ 52,351	$ 43,632	$ 96,146	$ 109,756
Chief Executive Officer
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation			26,400
Cost of revenue
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation	1,119	936	2,292	1,816
Sales and marketing
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation	9,116	6,801	16,109	12,451
Technology and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation	21,666	18,399	40,583	33,908
General and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share-based compensation	$ 20,450	$ 17,496	$ 37,162	$ 61,581