Other Assets Other Assets, Summary of Net Gains/(Losses) (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Equity Securities, FV-NI, Gain (Loss)	[1]	$ (6)	$ (4)	$ (3)	$ 10
Equity Securities without Readily Determinable Fair Value, Downward Price Adjustment, Annual Amount		0	0	0	0
Equity Securities without Readily Determinable Fair Value, Upward Price Adjustment, Annual Amount	[1]	16	7	16	30
Equity Securities, FV-NI, Realized Gain (Loss)		0	0	0	0
Equity Securities [Member]
Unrealized Gain (Loss) on Securities		$ 10	$ 3	$ 13	$ 40

[1] Recognized in Other noninterest income in the Company’s Consolidated Statements of Income.