Commitments, Guarantees and Contingencies - Commitments (Details) $ in Millions	Sep. 30, 2025 USD ($)
Commitment, Fiscal Year Maturity
Less than 1 (year)	$ 198,499
1-3 (years)	62,465
3-5 (years)	87,957
Over 5 (years)	17,711
Total	366,632
Forward-Starting Secured Financing Receivables
Commitment, Fiscal Year Maturity
Less than 1 (year)	141,793
1-3 (years)	3,554
3-5 (years)	0
Over 5 (years)	0
Total	145,347
Central counterparty
Commitment, Fiscal Year Maturity
Less than 1 (year)	14,298
1-3 (years)	0
3-5 (years)	0
Over 5 (years)	0
Total	14,298
Underwriting
Commitment, Fiscal Year Maturity
Less than 1 (year)	1,422
1-3 (years)	0
3-5 (years)	0
Over 5 (years)	0
Total	1,422
Investment activities
Commitment, Fiscal Year Maturity
Less than 1 (year)	2,533
1-3 (years)	313
3-5 (years)	76
Over 5 (years)	471
Total	3,393
Letters of credit and other financial guarantees
Commitment, Fiscal Year Maturity
Less than 1 (year)	26
1-3 (years)	0
3-5 (years)	0
Over 5 (years)	5
Total	31
Corporate
Commitment, Fiscal Year Maturity
Less than 1 (year)	15,253
1-3 (years)	47,884
3-5 (years)	77,007
Over 5 (years)	10,225
Total	150,369
Lending commitments participated to third parties	12,877
Secured lending facilities
Commitment, Fiscal Year Maturity
Less than 1 (year)	7,152
1-3 (years)	6,604
3-5 (years)	10,133
Over 5 (years)	6,086
Total	29,975
Commercial and Residential real estate
Commitment, Fiscal Year Maturity
Less than 1 (year)	673
1-3 (years)	181
3-5 (years)	215
Over 5 (years)	465
Total	1,534
Securities-based lending and Other
Commitment, Fiscal Year Maturity
Less than 1 (year)	15,349
1-3 (years)	3,929
3-5 (years)	526
Over 5 (years)	459
Total	$ 20,263

Commitments participated to third parties.

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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477314/942-235-S99-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480738/235-10-S50-4

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480678/235-10-S99-3

+ Details

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- Definition

Amount of commitment classified as other to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of commitment classified as other to be paid in fourth and fifth fiscal years following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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Amount of commitment classified as other to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of commitment classified as other to be paid in second and third fiscal years following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- References

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