Loans and Allowance for Credit Losses - Net Loans (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	$ 35,141	$ 32,532
Allowance for credit losses	(86)	(87)
Loans, net of allowance	35,055	32,445
Geographic Distribution, Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	22,549	22,114
Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	12,592	10,418
Fund Finance \| Geographic Distribution, Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	11,649	12,396
Fund Finance \| Geographic Distribution, Domestic \| Private Equity Capital Call Finance Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	8,254	9,147
Fund Finance \| Geographic Distribution, Domestic \| Real Money Funds
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	6,555	6,397
Fund Finance \| Geographic Distribution, Domestic \| Collateralized Loan Obligations
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	2,483	2,913
Fund Finance \| Geographic Distribution, Domestic \| Business Development
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	1,243	1,387
Fund Finance \| Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	7,746	7,778
Leveraged loans \| Geographic Distribution, Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	3,147	3,106
Leveraged loans \| Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	1,283	1,328
Overdrafts \| Geographic Distribution, Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	3,181	1,796
Overdrafts \| Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	3,563	1,312
Other \| Securities Finance Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	1,529	1,784
Other \| Municipal Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	462	455
Other \| Other Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	22	23
Other \| Geographic Distribution, Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	2,014	2,262
Commercial real estate \| Geographic Distribution, Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, gross	$ 2,558	$ 2,554

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Amount excluding accrued interest, of allowance for credit loss on financing receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
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-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 3B
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL120267963-210447

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