Derivative Instruments - Change in Unrealized Gains (Losses) in AOCI (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	$ 571	$ 536
Change in fair value, net of tax	(10)
Reclassification into earnings, net of tax	(1)
Ending Balance	1,098	(194)
Cash Flow Hedges | Foreign exchange forward contracts
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	14	2
Change in fair value, net of tax	5	(9)
Reclassification into earnings, net of tax	(5)	2
Ending Balance	14	(5)
Cash Flow Hedges | Interest rate swap contracts
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	0	0
Change in fair value, net of tax	2	0
Reclassification into earnings, net of tax	0	0
Ending Balance	2	0
Net Investment Hedges
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning Balance	(81)	(8)
Change in fair value, net of tax	11	24
Reclassification into earnings, net of tax	0	0
Ending Balance	$ (70)	$ 16