Commitments, Guarantees and Contingencies - Commitments (Details) $ in Millions	Dec. 31, 2025 USD ($)
Commitment, Fiscal Year Maturity
Less than 1 (year)	$ 200,929
1-3 (years)	62,730
3-5 (years)	90,185
Over 5 (years)	13,250
Total	367,094
Forward-starting secured financing receivables
Commitment, Fiscal Year Maturity
Less than 1 (year)	138,050
1-3 (years)	2,782
3-5 (years)	0
Over 5 (years)	0
Total	140,832
Central counterparty
Commitment, Fiscal Year Maturity
Less than 1 (year)	14,062
1-3 (years)	0
3-5 (years)	0
Over 5 (years)	0
Total	14,062
Investment activities
Commitment, Fiscal Year Maturity
Less than 1 (year)	2,319
1-3 (years)	94
3-5 (years)	80
Over 5 (years)	503
Total	2,996
Letters of credit and other financial guarantees
Commitment, Fiscal Year Maturity
Less than 1 (year)	30
1-3 (years)	3
3-5 (years)	0
Over 5 (years)	5
Total	38
Corporate
Commitment, Fiscal Year Maturity
Less than 1 (year)	23,398
1-3 (years)	48,607
3-5 (years)	79,273
Over 5 (years)	5,843
Total	157,121
Lending commitments participated to third parties	12,164
Secured lending facilities
Commitment, Fiscal Year Maturity
Less than 1 (year)	5,341
1-3 (years)	8,035
3-5 (years)	10,429
Over 5 (years)	5,930
Total	29,735
Commercial and Residential real estate
Commitment, Fiscal Year Maturity
Less than 1 (year)	66
1-3 (years)	115
3-5 (years)	173
Over 5 (years)	465
Total	819
Securities-based lending and Other loans
Commitment, Fiscal Year Maturity
Less than 1 (year)	17,663
1-3 (years)	3,094
3-5 (years)	230
Over 5 (years)	504
Total	$ 21,491

Commitments participated to third parties.

No definition available.

Name:	ms_CommitmentsParticipatedToThirdParties
Namespace Prefix:	ms_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

Name:	us-gaap_OtherCommitment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

+ Details

Name:	us-gaap_OtherCommitmentDueAfterFifthYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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.

+ Details

Name:	us-gaap_OtherCommitmentDueInFourthAndFifthYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ Details

Name:	us-gaap_OtherCommitmentDueInNextTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

No definition available.

+ Details

Name:	us-gaap_OtherCommitmentDueInSecondAndThirdYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_OtherCommitmentFiscalYearMaturityAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_OtherCommitmentsAxis=ms_ForwardStartingSecuredFinancingReceivablesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OtherCommitmentsAxis=ms_CentralCounterpartyCommitmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OtherCommitmentsAxis=ms_CommitmentsInvestmentActivitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_OtherCommitmentsAxis=ms_CommitmentsLettersOfCreditAndOtherFinancialGuaranteesObtainedToSatisfyCollateralRequirementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CommercialLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=ms_SecuredLendingFacilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_RealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=ms_SecuritiesBasedLendingandOtherLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: