Loans and Allowance for Credit Losses - Net Loans (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	$ 36,631	$ 32,150
Allowance for credit losses	(135)	(97)
Loans, net of allowance	36,496	32,053
Geographic Distribution, Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	23,065	21,248
Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	13,566	10,902
Fund Finance \| Securities Finance Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	2,230	1,510
Fund Finance \| Municipal Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	276	321
Fund Finance \| Other Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	5	42
Fund Finance \| Geographic Distribution, Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	13,697	12,154
Fund Finance \| Geographic Distribution, Domestic \| 40 Act Funds
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	6,630	6,610
Fund Finance \| Geographic Distribution, Domestic \| Private Equity Capital Call Finance Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	9,690	7,570
Fund Finance \| Geographic Distribution, Domestic \| Business Development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	1,050	1,110
Fund Finance \| Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	4,956	3,949
Leveraged loans \| Geographic Distribution, Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	2,412	2,431
Leveraged loans \| Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	1,194	1,118
Overdrafts \| Geographic Distribution, Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	1,225	1,707
Overdrafts \| Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	1,047	1,094
Collateralized loan obligations \| Geographic Distribution, Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	150	100
Collateralized loan obligations \| Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	6,369	4,741
Other \| Geographic Distribution, Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	2,512	1,871
Commercial real estate \| Geographic Distribution, Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	$ 3,069	$ 2,985

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Paragraph 3B
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-Paragraph 5
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-Publisher FASB
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