Revenue from Contracts with Customers - Summary of Revenue Disaggregated by Platform (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation Of Revenue [Line Items]
Total revenue	$ 265,403	$ 208,232
Mobile Online Game [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	182,833	139,830
Other Online game [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	17,331	21,723
Online Game [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	200,164	161,553
Mobile Advertising and Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	63,260	42,771
Web Advertising and Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	1,979	3,908
Advertising and Other [Member]
Disaggregation Of Revenue [Line Items]
Total revenue	$ 65,239	$ 46,679