Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Tax Disclosure [Abstract]
(Provision) benefit for income taxes	$ (38)	$ (126)	$ (377)	$ 9
Effective income tax rate	5.70%	16.10%	16.60%	(0.20%)
Discrete tax expense (benefit)	$ (117)		$ (120)
Tax expense (benefit) from changes in UK tax rate	(100)
Benefit from preparation of tax return	22	$ 58		$ 58
Provision (benefit) from restructuring and other corporate matters, depreciation on abandoned technology and other discrete tax items	$ (18)	$ 2	$ (153)	$ (27)
Percentage point decrease in effective tax rate	17.50%	4.30%	5.40%	21.90%
Transfer of intangible assets				$ 768
Benefit from bankruptcy of investee				32
Provision for gain on sale of assets				$ 163
Decrease in uncertain tax positions	$ 65		$ 65