Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Cash Payments:
Interest	$ 2,074	$ 2,017
Income taxes paid, net of refunds received	62	18
Transfers:
Portfolio loans and leases to loans and leases held for sale	309	138
Loans and leases held for sale to portfolio loans and leases	2	2
Portfolio loans and leases to OREO	11	11
Bank premises and equipment to OREO	1	12
Supplemental Disclosures:
Non-cash consideration transferred for the Comerica acquisition	$ 12,676	$ 0

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