Changes in Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Other Comprehensive Income (Loss) Net of Tax, Period Change [Abstract]
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	$ 218	$ 142	$ (53)
AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax	36	173	111
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax	(47)	(45)	(25)
Accumulated Other Comprehensive Income (Loss), Net of Tax	207	270	33
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	95	228
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax	(77)	116
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments, Net of Tax	(5)	(22)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	13	322
Gain (Loss) on Derivative Used in Net Investment Hedge, after Tax	(19)	(33)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax	(60)	(54)
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax	3	2
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(76)	(86)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	76	195	(21)
Net change in derivative financial instruments	(137)	62	110
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	(1)	(20)	2
Other Comprehensive Income (Loss), Net of Tax	$ (63)	$ 237	$ 91