Loans, Leases, and Allowance for Credit Losses (Collateral-Dependent Loans) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost	$ 24	$ 47
Commercial and industrial | Commercial | Single family residential
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost	$ 8
Weighted average LTV	39.00%
Commercial and industrial | Commercial | Corporate assets, Single family residential
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost		$ 27
Weighted average LTV		55.00%
Owner-occupied | Commercial | Office building
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost	$ 8	$ 11
Weighted average LTV	40.00%	40.00%
Term | Commercial real estate | Multi-family
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost	$ 2
Weighted average LTV	37.00%
Term | Commercial real estate | Multi-family, Retail
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost		$ 2
Weighted average LTV		28.00%
Home equity credit line | Consumer | Single family residential
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost	$ 4	$ 5
Weighted average LTV	35.00%	45.00%
1-4 family residential | Consumer | Single family residential
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost	$ 2	$ 2
Weighted average LTV	38.00%	35.00%