Loans, Lending Commitments and Related Allowance for Credit Losses - Loans by Interest Rate Type (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fixed Rate	$ 60,751	$ 60,911
Floating or Adjustable Rate	234,337	218,315
Corporate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fixed Rate	86	1
Floating or Adjustable Rate	23,323	14,478
Secured lending facilities
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fixed Rate	525	525
Floating or Adjustable Rate	71,904	70,440
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fixed Rate	331	327
Floating or Adjustable Rate	8,156	8,032
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fixed Rate	32,555	32,377
Floating or Adjustable Rate	40,978	40,031
Securities-based lending and Other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Fixed Rate	27,254	27,681
Floating or Adjustable Rate	$ 89,976	$ 85,334