Credit Quality and the Allowance for Loan and Lease Losses - Summary of Loans Modified in a TDR (Details) $ in Millions	12 Months Ended
Dec. 31, 2022 USD ($) loan	Dec. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($) loan
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Year \| loan	10,091	10,882	6,531
Amortized Cost Basis of Loans Modified in a TDR During the Year	$ 545	$ 450	$ 525
Increase (Decrease) to ALLL Upon Modification	19	12	22
Charge-offs Recognized Upon Modification	$ 9	$ 1	$ 8
Commercial \| Commercial and industrial loans
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Year \| loan	89	86	124
Amortized Cost Basis of Loans Modified in a TDR During the Year	$ 234	$ 150	$ 305
Increase (Decrease) to ALLL Upon Modification	3	1	26
Charge-offs Recognized Upon Modification	$ 9	$ 0	$ 7
Commercial \| Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Year \| loan	12	10	43
Amortized Cost Basis of Loans Modified in a TDR During the Year	$ 7	$ 8	$ 58
Increase (Decrease) to ALLL Upon Modification	0	0	(11)
Charge-offs Recognized Upon Modification	$ 0	$ 0	$ 0
Commercial \| Commercial mortgage nonowner-occupied loans
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Year \| loan	7	5	19
Amortized Cost Basis of Loans Modified in a TDR During the Year	$ 24	$ 29	$ 44
Increase (Decrease) to ALLL Upon Modification	0	0	(2)
Charge-offs Recognized Upon Modification	$ 0	$ 0	$ 0
Commercial \| Commercial construction loans
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Year \| loan	3	1	3
Amortized Cost Basis of Loans Modified in a TDR During the Year	$ 10	$ 34	$ 21
Increase (Decrease) to ALLL Upon Modification	(2)	0	1
Charge-offs Recognized Upon Modification	$ 0	$ 0	$ 0
Residential Mortgage
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Year \| loan	1,073	519	424
Amortized Cost Basis of Loans Modified in a TDR During the Year	$ 163	$ 93	$ 58
Increase (Decrease) to ALLL Upon Modification	7	4	1
Charge-offs Recognized Upon Modification	$ 0	$ 0	$ 0
Consumer \| Home equity
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Year \| loan	231	206	147
Amortized Cost Basis of Loans Modified in a TDR During the Year	$ 16	$ 10	$ 7
Increase (Decrease) to ALLL Upon Modification	(3)	(3)	(4)
Charge-offs Recognized Upon Modification	$ 0	$ 0	$ 0
Consumer \| Indirect secured consumer loans
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Year \| loan	3,394	4,567	70
Amortized Cost Basis of Loans Modified in a TDR During the Year	$ 63	$ 96	$ 0
Increase (Decrease) to ALLL Upon Modification	2	1	0
Charge-offs Recognized Upon Modification	$ 0	$ 0	$ 0
Consumer \| Credit card
Financing Receivable, Modifications
Number of Loans Modified in a TDR During the Year \| loan	5,282	5,488	5,701
Amortized Cost Basis of Loans Modified in a TDR During the Year	$ 28	$ 30	$ 32
Increase (Decrease) to ALLL Upon Modification	12	9	11
Charge-offs Recognized Upon Modification	$ 0	$ 1	$ 1

Amount of credit loss expense (reversal of expense) on financing receivable from change in methodology. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 11
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919244-210447

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
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