Loans, Lending Commitments and Related Allowance for Credit Losses - Past Due Loans Held for Investment before Allowance (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 198,332	$ 174,956
Past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	185	209
Corporate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	6,858	5,567
Corporate | Past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	44	0
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	52,904	44,251
Residential real estate | Past due
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 141	$ 209