Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022
Cash Payments:
Interest	$ 2,554	$ 487
Income taxes	496	124
Transfers:
Portfolio loans and leases to loans and leases held for sale	281	105
Loans and leases held for sale to portfolio loans and leases	5	406
Portfolio loans and leases to OREO	9	5
Bank premises and equipment to OREO	29	22
Supplemental Disclosures:
Net additions to lease liabilities under operating leases	56	102
Net (reductions) additions to lease liabilities under finance leases	$ (6)	$ 29

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