Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Cash Payments:
Interest	$ 1,071	$ 1,107
Income taxes paid, net of refunds received	9	(3)
Transfers:
Portfolio loans and leases to loans and leases held for sale	199	38
Loans and leases held for sale to portfolio loans and leases	2	2
Portfolio loans and leases to OREO	6	5
Bank premises and equipment to OREO	1	4
Supplemental Disclosures:
Non-cash consideration transferred for the Comerica acquisition	$ 12,676	$ 0

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