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, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
(Loss) Gain recognized in Accumulated other comprehensive loss	$ (9)
(Loss) Gain recognized in Accumulated other comprehensive loss		$ (18)	$ 18
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	(14)
Gain (loss) reclassified from accumulated other comprehensive loss into income (effective portion)		(11)	(1)
Total revenue
Derivative [Line Items]
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	(12)
Gain (loss) reclassified from accumulated other comprehensive loss into income (effective portion)		0	0
Compensation and benefits
Derivative [Line Items]
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	(1)
Gain (loss) reclassified from accumulated other comprehensive loss into income (effective portion)		1	14
Other general expense
Derivative [Line Items]
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	0
Gain (loss) reclassified from accumulated other comprehensive loss into income (effective portion)		(2)	(5)
Interest expense
Derivative [Line Items]
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	(1)
Gain (loss) reclassified from accumulated other comprehensive loss into income (effective portion)		(2)	(1)
Other income (expense)
Derivative [Line Items]
Gain (loss) reclassified from accumulated other comprehensive loss, after adoption of ASU 2017-02	$ 0
Gain (loss) reclassified from accumulated other comprehensive loss into income (effective portion)		$ (8)	$ (9)