Income Taxes - Deferred Tax Assets and Deferred Tax Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets:
Net operating loss, capital loss and credits	$ 158	$ 136
Accruals and allowances	214	168
Stock-based compensation	15	22
Amortizable tax basis in intangibles	4,287	4,757
Net deferred tax assets	4,674	5,083
Valuation allowance	(102)	(65)
Deferred tax assets, net of valuation allowance	4,572	5,018
Deferred tax liabilities:
Unremitted foreign earnings	(2,610)	(2,930)
Acquisition-related intangibles	(37)	(46)
Depreciation and amortization	(131)	(132)
Net unrealized gain	(2)	(27)
Available-for-sale securities	(61)	(15)
Deferred tax liabilities	(2,841)	(3,150)
Net deferred tax assets	$ 1,731	$ 1,868