Borrowings and Other Secured Financings - Other Secured Financings (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Original maturities:
Greater than one year	$ 5,048	$ 6,772
One year or less	4,353	2,036
Failed sales	2,580	658
Total	$ 11,981	$ 9,466

Secured financings with original maturities greater than one year.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Secured financings with original maturities one year or less.

+ References

No definition available.

+ Details

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Namespace Prefix:	ms_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Secured financing other than securities sold under agreements to repurchase and securities loaned.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 15
-Paragraph 83
-URI http://asc.fasb.org/extlink&oid=117415099&loc=d3e34841-113949

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying amount of liabilities associated with financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

+ Details

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