Derivative Instruments and Hedging Activities (Derivatives Not Designated As Hedges) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Derivatives Not Designated As Hedging Instruments [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Noninterest (Other) Income/(Expense)	$ 2	$ 6	$ 17	$ 12