Supplemental Cash Flow (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Cash Payments:
Interest	$ 431	$ 746
Income taxes	500	419
Transfers:
Portfolio loans and leases to loans and leases held for sale	414	713
Loans and leases held for sale to portfolio loans and leases	38	39
Portfolio loans and leases to OREO	7	11
Loans and leases held for sale to OREO	0	2
Bank premises and equipment to OREO	19	2
Supplemental Disclosures:
Net additions to lease liabilities under operating leases	59	35
Net additions to lease liabilities under finance leases	29	90
Accounts, Notes, Loans and Financing Receivable
Portfolio loans and leases to loans and leases held for sale	414	713
Residential mortgage loans \| GNMA loans
Transfers:
Portfolio loans and leases to loans and leases held for sale	154	668
Accounts, Notes, Loans and Financing Receivable
Portfolio loans and leases to loans and leases held for sale	$ 154	$ 668

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