Loans and Allowance for Credit Losses - Net Loans (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	$ 39,376	$ 36,631
Allowance for credit losses	(136)	(135)
Loans, net of allowance	39,240	36,496
Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	23,380	23,065
Domestic | Collateralized loan obligations in loan form
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	190	150
Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	15,996	13,566
Non-U.S. | Collateralized loan obligations in loan form
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	7,380	6,369
Fund Finance | Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	13,808	13,697
Fund Finance | Domestic | Private Equity Capital Call Finance Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	10,200	9,690
Fund Finance | Domestic | Real Money Funds
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	6,730	6,630
Fund Finance | Domestic | Business Development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	1,370	1,050
Fund Finance | Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	5,630	4,956
Leveraged loans | Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	2,357	2,412
Leveraged loans | Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	1,111	1,194
Overdrafts | Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	1,791	1,225
Overdrafts | Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	1,875	1,047
Other | Securities Finance Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	2,120	2,230
Other | Municipal Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	250	276
Other | Other Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	2	5
Other | Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	2,376	2,512
Commercial real estate | Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	2,858	$ 3,069
Excluding Overdrafts | Floating Rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	32,900
Excluding Overdrafts | Fixed Rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	$ 2,800