Amount of investment in qualified affordable housing projects.

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Amount of loss contingency liability.

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of commitment or contingent commitments to qualified affordable housing project investments.

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Investments (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Investments (Narrative) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Investment Holdings [Line Items]
Proceeds from sales of available-for-sale securities	$ 0	$ 0	$ 0	$ 0
Recognized gains (losses) on available-for-sale securities	0	$ 0	0	$ 0
Affordable housing project equity method investments	301		301		$ 298
Contingent liabilities related to affordable housing project equity method investments	47		47		59
Payment Services [Member]
Investment Holdings [Line Items]
Equity securities without readily determinable fair value	25		25		42
Other Assets [Member] \| Community Reinvestment Act [Member]
Investment Holdings [Line Items]
Equity method investments	335		335		336
Other Liabilities [Member] \| Community Reinvestment Act [Member]
Investment Holdings [Line Items]
Contingent liabilities related to equity method investments	$ 63		$ 63		$ 74