Credit Quality and the Allowance for Loan and Lease Losses - Summary of Gross Charge-Offs Within the Commercial Portfolio Segments, by Class and Vintage (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Financing Receivable, Modifications
Total	$ 173	$ 146
Commercial
Financing Receivable, Modifications
Year One	0	0
Year Two	6	1
Year Three	4	2
Year Four	1	0
Year Five	0	0
Prior	13	0
Revolving Loans	43	37
Total	67	40
Commercial \| Commercial and industrial loans
Financing Receivable, Modifications
Year One	0	0
Year Two	6	1
Year Three	4	2
Year Four	1	0
Year Five	0	0
Prior	0	0
Revolving Loans	43	37
Total	54	40
Commercial \| Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
Year One	0	0
Year Two	0	0
Year Three	0	0
Year Four	0	0
Year Five	0	0
Prior	11	0
Revolving Loans	0	0
Total	11	0
Commercial \| Commercial leases
Financing Receivable, Modifications
Year One	0	0
Year Two	0	0
Year Three	0	0
Year Four	0	0
Year Five	0	0
Prior	2	0
Revolving Loans	0	0
Total	$ 2	$ 0

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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