Derivatives and Hedging Instruments - Gain (Loss) on Derivatives Not Designated as Hedging Instruments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Derivative [Line Items]
Interest expense	$ 91	$ 67	$ 174	$ 130
(Gain) loss reclassified from AOCI	24	(5)	43	(6)
Net derivative-related gains reclassified into earnings	80		80
Cost of services
Derivative [Line Items]
Cost of revenue	970	982	1,939	1,945
Foreign exchange contracts | Other income (expense), net
Derivative [Line Items]
Derivative instruments not designated as hedging instruments, gain (loss), net	(3)	(12)	(8)	(18)
Interest rate contracts | Cost of services | Cash Flow Hedging
Derivative [Line Items]
(Gain) loss reclassified from AOCI	(19)	5	(34)	6
Interest rate contracts | Cost of services | Cost of services
Derivative [Line Items]
Derivative instruments not designated as hedging instruments, gain (loss), net	14	0	14	0
Interest rate contracts | Interest expense | Cash Flow Hedging
Derivative [Line Items]
(Gain) loss reclassified from AOCI	$ (5)	$ 0	$ (9)	$ 0