Supplemental Cash Flow (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Cash Payments:
Interest	$ 158	$ 182
Income taxes	11	209
Transfers:
Portfolio loans and leases to loans and leases held for sale	71	220
Loans and leases held for sale to portfolio loans and leases	402	10
Portfolio loans and leases to OREO	2	4
Bank premises and equipment to OREO	15	16
Supplemental Disclosures:
Net additions to lease liabilities under operating leases	31	15
Net additions to lease liabilities under finance leases	$ 3	$ 18

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