Credit Quality and the Allowance for Loan and Lease Losses - Summary of Subsequent Defaults (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022 USD ($) contract	Sep. 30, 2021 USD ($) contract	Sep. 30, 2022 USD ($) contract	Sep. 30, 2021 USD ($) contract
Financing Receivable, Modifications
Number of Contracts \| contract	203	138	563	300
Amortized Cost \| $	$ 11	$ 2	$ 29	$ 38
Commercial \| Commercial and industrial loans
Financing Receivable, Modifications
Number of Contracts \| contract	1	4	8	5
Amortized Cost \| $	$ 0	$ 1	$ 0	$ 1
Commercial \| Commercial construction loans
Financing Receivable, Modifications
Number of Contracts \| contract			1
Amortized Cost \| $			$ 2
Commercial \| Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
Number of Contracts \| contract		2		2
Amortized Cost \| $		$ 0		$ 0
Commercial \| Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
Number of Contracts \| contract		1		2
Amortized Cost \| $		$ 0		$ 25
Residential Mortgage
Financing Receivable, Modifications
Number of Contracts \| contract	70	10	176	61
Amortized Cost \| $	$ 11	$ 1	$ 24	$ 8
Consumer \| Home equity
Financing Receivable, Modifications
Number of Contracts \| contract	6	5	21	22
Amortized Cost \| $	$ 0	$ 0	$ 1	$ 1
Consumer \| Indirect secured consumer loans
Financing Receivable, Modifications
Number of Contracts \| contract	43	31	102	89
Amortized Cost \| $	$ 0	$ 0	$ 1	$ 2
Consumer \| Credit card
Financing Receivable, Modifications
Number of Contracts \| contract	83	85	255	119
Amortized Cost \| $	$ 0	$ 0	$ 1	$ 1

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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