Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024
Cash Payments:
Interest	$ 3,094	$ 3,795
Income taxes	120	126
Transfers:
Portfolio loans and leases to loans and leases held for sale	173	333
Loans and leases held for sale to portfolio loans and leases	4	3
Portfolio loans and leases to OREO	17	16
Bank premises and equipment to OREO	14	7
Available-for-sale debt securities to held-to-maturity securities	0	11,593
Supplemental Disclosures:
Net additions to lease liabilities under operating leases	131	59
Net additions to lease liabilities under finance leases	29	45
Lease payments received for operating lease equipment	61	78
Cash Paid for Amounts Included in the Measurement of Lease Liabilities
Operating cash flows from operating leases	72	71
Operating cash flows from finance leases	5	4
Financing cash flows from finance leases	$ 13	$ 14

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