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	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Financing Receivable, Modifications
Total	$ 181	$ 194	$ 368	$ 366
Commercial
Financing Receivable, Modifications
Year One			2	0
Year Two			2	8
Year Three			2	23
Year Four			1	6
Year Five			0	6
Prior			6	14
Revolving Loans			138	99
Total	$ 73	$ 90	151	156
Commercial \| Commercial and industrial loans
Financing Receivable, Modifications
Year One			2	0
Year Two			2	8
Year Three			2	22
Year Four			1	5
Year Five			0	3
Prior			6	1
Revolving Loans			138	98
Total			151	137
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	3
Prior			0	11
Revolving Loans			0	1
Total			0	15
Commercial \| Commercial leases
Financing Receivable, Modifications
Year One			0	0
Year Two			0	0
Year Three			0	1
Year Four			0	1
Year Five			0	0
Prior			0	2
Revolving Loans			0	0
Total			$ 0	$ 4

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