The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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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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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, 2020	Dec. 31, 2019	Dec. 31, 2018
Derivative [Line Items]
Gain (Loss) recognized in Accumulated other comprehensive loss	$ 1	$ (9)
Gain (Loss) recognized in Accumulated other comprehensive loss			$ (18)
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	(15)	(14)
Gain (loss) reclassified from accumulated other comprehensive loss, before adoption of ASU 2017-02			(11)
Total revenue
Derivative [Line Items]
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	(14)	(12)
Gain (loss) reclassified from accumulated other comprehensive loss, before adoption of ASU 2017-02			0
Compensation and benefits
Derivative [Line Items]
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	0	(1)
Gain (loss) reclassified from accumulated other comprehensive loss, before adoption of ASU 2017-02			1
Other general expense
Derivative [Line Items]
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	0	0
Gain (loss) reclassified from accumulated other comprehensive loss, before adoption of ASU 2017-02			(2)
Interest expense
Derivative [Line Items]
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	(1)	(1)
Gain (loss) reclassified from accumulated other comprehensive loss, before adoption of ASU 2017-02			(2)
Other income (expense)
Derivative [Line Items]
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	$ 0	$ 0
Gain (loss) reclassified from accumulated other comprehensive loss, before adoption of ASU 2017-02			$ (8)