Balance Sheet Components - Schedule of Accounts Payable and Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Accounts Payable And Accrued Liabilities Current [Abstract]
Accounts payable	$ 62,002	$ 56,576
Accrued royalty expense	8,294	7,939
Accrued inventory	8,392	6,008
Accrued payroll and related expenses	14,816	12,217
Accrued cost of revenue	26,191	22,830
Payments due to content publishers	47,630	32,463
Operating lease liability, current	15,946
Customer prepayments	5,069	3,124
Taxes and related liabilities	840	1,314
Accrued legal fees	2,845
Other accrued expenses	9,707	6,091
Total Accounts Payable and Accrued Liabilities	$ 201,732	$ 148,562