Supplemental Cash Flow (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Cash Payments:
Interest	$ 205	$ 256
Income taxes	52	336
Transfers:
Portfolio loans and leases to loans and leases held for sale	73	337
Loans and leases held for sale to portfolio loans and leases	403	20
Portfolio loans and leases to OREO	3	9
Bank premises and equipment to OREO	18	17
Supplemental Disclosures:
Net additions to lease liabilities under operating leases	77	31
Net additions to lease liabilities under finance leases	$ 15	$ 25

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