Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income tax rate	24.40%	25.40%
Income tax rate, change in enacted tax rate, percent	1.20%	1.10%
Valuation Allowance Rollforward [Roll Forward]
Balance at beginning of year		$ 2,324
Additions to valuation allowance charged to income tax expense		32
Reductions to valuation allowance credited to income tax benefit		(141)
Foreign currency translation		5
Balance at end of year	$ 2,220	2,220
Unrecognized tax benefits	66	66	$ 64
Unrecognized tax benefits that would impact the effective tax rate	40	40	40
Possible decrease in unrecognized tax benefits	3	3
Unrecognized tax benefits that would impact deferred taxes	$ 26	$ 26	$ 24