Income Taxes - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Tax expense (benefit) attributable to enactment of TCJA		$ (32)	$ 257
GILTI, percent	0.30%	0.20%
Undistributed indefinitely reinvested earnings of certain foreign subsidiaries	$ 4,100
Unrecognized tax benefits	149	$ 108	94	$ 71
Unrecognized tax benefits that would impact effective tax rate	140	100	87
Maximum estimated income tax expense change in unrecognized tax benefit in the next 12 months	4
Interest expense for tax examination	5	1
Interest accrued for tax examination	$ 10	$ 8	$ 8