Income Taxes - Components of Net Deferred Tax Assets (Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Allowance for sales returns and price protection	$ 25	$ 47
Accrued expenses	26	31
Deferred revenue	136	245
Tax attributes carryforwards	81	71
Share-based compensation	69	59
Acquired intangibles	43	149
U.S. deferred taxes on foreign earnings	263	0
Other	28	61
Deferred tax assets	671	663
Valuation allowance	(61)	0
Deferred tax assets, net of valuation allowance	610	663
Deferred tax liabilities:
Acquired intangibles	(140)	(146)
Capitalized software development expenses	(57)	(55)
Other	(26)	(24)
Deferred tax liabilities	(223)	(225)
Net deferred tax assets	$ 387	$ 438