Credit Quality and the Allowance for Loan and Lease Losses - Summary of Subsequent Defaults (Details) $ in Millions	12 Months Ended
Dec. 31, 2022 USD ($) contract	Dec. 31, 2021 USD ($) contract	Dec. 31, 2020 USD ($) contract
Financing Receivable, Modifications
Number of Contracts \| contract	796	467	457
Amortized Cost \| $	$ 40	$ 41	$ 43
Commercial \| Commercial and industrial loans
Financing Receivable, Modifications
Number of Contracts \| contract	8	7	13
Amortized Cost \| $	$ 0	$ 1	$ 5
Commercial \| Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
Number of Contracts \| contract	2	3	8
Amortized Cost \| $	$ 0	$ 1	$ 3
Commercial \| Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
Number of Contracts \| contract	1	2	3
Amortized Cost \| $	$ 0	$ 25	$ 11
Commercial \| Commercial construction loans
Financing Receivable, Modifications
Number of Contracts \| contract	1
Amortized Cost \| $	$ 2
Residential Mortgage
Financing Receivable, Modifications
Number of Contracts \| contract	247	82	149
Amortized Cost \| $	$ 33	$ 10	$ 23
Consumer \| Home equity
Financing Receivable, Modifications
Number of Contracts \| contract	24	28	6
Amortized Cost \| $	$ 1	$ 1	$ 0
Consumer \| Indirect secured consumer loans
Financing Receivable, Modifications
Number of Contracts \| contract	157	130	18
Amortized Cost \| $	$ 3	$ 2	$ 0
Consumer \| Credit card
Financing Receivable, Modifications
Number of Contracts \| contract	356	215	260
Amortized Cost \| $	$ 1	$ 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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