Derivatives and Hedging - Schedule of Derivative Gains (Losses) Recognized in the Consolidated Financial Statements (Details) - Foreign exchange contracts - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative [Line Items]
Gain (loss) recognized in Accumulated other comprehensive loss	$ (6)	$ 5	$ 5	$ (8)
Derivative gains (losses) reclassified from accumulated other comprehensive loss	0	(2)	(1)	(13)
Total revenue
Derivative [Line Items]
Derivative gains (losses) reclassified from accumulated other comprehensive loss	(1)	(3)	(2)	(12)
Compensation and benefits
Derivative [Line Items]
Derivative gains (losses) reclassified from accumulated other comprehensive loss	1	1	1	0
Interest expense
Derivative [Line Items]
Derivative gains (losses) reclassified from accumulated other comprehensive loss	$ 0	$ 0	$ 0	$ (1)