Loans and Leases - Schedule Of Troubled Debt Restructurings Occurring During The Year (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($) loan	Jun. 30, 2020 USD ($) loan	Jun. 30, 2021 USD ($) loan	Jun. 30, 2020 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	58	61	110	106
Pre-Modification Outstanding Recorded Investment	$ 25	$ 13	$ 50	$ 21
Post-Modification Outstanding Recorded Investment	$ 25	$ 13	$ 47	$ 19
Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	33	44	54	62
Pre-Modification Outstanding Recorded Investment	$ 6	$ 8	$ 10	$ 10
Post-Modification Outstanding Recorded Investment	$ 6	$ 8	$ 10	$ 10
Consumer \| Credit Card and Other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	15	16	28	40
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 0	$ 0
C&I \| Commercial \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	10	1	27	4
Pre-Modification Outstanding Recorded Investment	$ 19	$ 5	$ 28	$ 11
Post-Modification Outstanding Recorded Investment	$ 19	$ 5	$ 27	$ 9
CRE \| Commercial \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	0	0	1	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 12	$ 0
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 10	$ 0
HELOC \| Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	7	4	19	12
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 2	$ 1
Post-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 2	$ 1
Real estate installment loans \| Consumer \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan	26	40	35	50
Pre-Modification Outstanding Recorded Investment	$ 6	$ 8	$ 8	$ 9
Post-Modification Outstanding Recorded Investment	$ 6	$ 8	$ 8	$ 9

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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