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, 2026	Mar. 31, 2025
Financing Receivable, Modifications
Total	$ 187	$ 173
Commercial
Financing Receivable, Modifications
Year One	0	0
Year Two	1	6
Year Three	0	4
Year Four	0	1
Year Five	0	0
Prior	6	13
Revolving Loans	70	43
Total	77	67
Commercial \| Commercial and industrial loans
Financing Receivable, Modifications
Year One	0	0
Year Two	1	6
Year Three	0	4
Year Four	0	1
Year Five	0	0
Prior	6	0
Revolving Loans	70	43
Total	77	54
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	0	11
Revolving Loans	0	0
Total	0	11
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	0	2
Revolving Loans	0	0
Total	$ 0	$ 2

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

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