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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Derivatives and Hedging - Schedule of amounts of derivative gains (losses) recognized in the Consolidated Financial Statements (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Derivative [Line Items]
Gain (loss) recognized in Accumulated other comprehensive loss	$ (12)		$ (8)
Gain (loss) recognized in Accumulated other comprehensive loss		$ (25)		$ (11)
Derivative gains (losses) reclassified from accumulated other comprehensive loss	(3)		(8)
Derivative gain (loss) reclassified from accumulated OCI into income, effective portion, net		(2)		(6)
Revenue
Derivative [Line Items]
Derivative gains (losses) reclassified from accumulated other comprehensive loss	(3)		(7)
Derivative gain (loss) reclassified from accumulated OCI into income, effective portion, net		0		0
Compensation and benefits
Derivative [Line Items]
Derivative gains (losses) reclassified from accumulated other comprehensive loss	0		0
Derivative gain (loss) reclassified from accumulated OCI into income, effective portion, net		0		1
Other general expenses
Derivative [Line Items]
Derivative gains (losses) reclassified from accumulated other comprehensive loss	0		0
Derivative gain (loss) reclassified from accumulated OCI into income, effective portion, net		(1)		(2)
Interest expense
Derivative [Line Items]
Derivative gains (losses) reclassified from accumulated other comprehensive loss	0		(1)
Derivative gain (loss) reclassified from accumulated OCI into income, effective portion, net		0		(1)
Other income (expense) (1)
Derivative [Line Items]
Derivative gains (losses) reclassified from accumulated other comprehensive loss	$ 0		$ 0
Derivative gain (loss) reclassified from accumulated OCI into income, effective portion, net		$ (1)		$ (4)