Derivatives and Hedging - Schedule of amounts of derivative gains (losses) recognized in the Consolidated Financial Statements (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Gain (loss) recognized in Accumulated other comprehensive loss	$ 0	$ 1
Gain (loss) recognized in Accumulated other comprehensive loss			$ (9)
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	(2)	(15)	(14)
Total revenue
Derivative [Line Items]
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	(3)	(14)	(12)
Compensation and benefits
Derivative [Line Items]
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	1	0	(1)
Interest expense
Derivative [Line Items]
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	$ 0	$ (1)	$ (1)

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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Amount, after tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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