Cover
| Cover | Sep. 20, 2019 |
| Schedule of Capitalization, Equity [Line Items] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Sep. 20, 2019 |
| Entity File Number | 1-11758 |
| Entity Registrant Name | Morgan Stanley |
| Entity Central Index Key | 0000895421 |
| Entity Tax Identification Number | 36-3145972 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | 1585 Broadway |
| Entity Address, City or Town | New York |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10036 |
| City Area Code | (212) |
| Local Phone Number | 761-4000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Elected Not To Use the Extended Transition Period | false |
| Common Class A [Member] | |
| Schedule of Capitalization, Equity [Line Items] | |
| Title of 12(b) Security | Common Stock, $0.01 par value |
| Trading Symbol | MS |
| Security Exchange Name | NYSE |
| Series A Preferred Stock [Member] | |
| Schedule of Capitalization, Equity [Line Items] | |
| Title of 12(b) Security | Non-Cumulative Preferred Stock, Series A, $0.01 par value |
| Trading Symbol | MS/PA |
| Security Exchange Name | NYSE |
| Series E Preferred Stock [Member] | |
| Schedule of Capitalization, Equity [Line Items] | |
| Title of 12(b) Security | Non-Cumulative Preferred Stock, Series E, $0.01 par value |
| Trading Symbol | MS/PE |
| Security Exchange Name | NYSE |
| Series F Preferred Stock [Member] | |
| Schedule of Capitalization, Equity [Line Items] | |
| Title of 12(b) Security | Non-Cumulative Preferred Stock, Series F, $0.01 par value |
| Trading Symbol | MS/PF |
| Security Exchange Name | NYSE |
| Series G Preferred Stock [Member] | |
| Schedule of Capitalization, Equity [Line Items] | |
| Title of 12(b) Security | Non-Cumulative Preferred Stock, Series G, $0.01 par value |
| Trading Symbol | MS/PG |
| Security Exchange Name | NYSE |
| Series I Preferred Stock [Member] | |
| Schedule of Capitalization, Equity [Line Items] | |
| Title of 12(b) Security | Non-Cumulative Preferred Stock, Series I, $0.01 par value |
| Trading Symbol | MS/PI |
| Security Exchange Name | NYSE |
| Series K Preferred Stock [Member] | |
| Schedule of Capitalization, Equity [Line Items] | |
| Title of 12(b) Security | Non-Cumulative Stock, Series K, $0.01 par value |
| Trading Symbol | MS/PK |
| Security Exchange Name | NYSE |
| Global Medium Term Notes Series A Fixed Rate Step Up Senior Notes Due 2026of Morgan Stanley Finance L L C [Member] | |
| Schedule of Capitalization, Equity [Line Items] | |
| Title of 12(b) Security | Global Medium-Term Notes, Series A, Fixed Rate Step-Up Senior Notes Due 2026 |
| Trading Symbol | MS/26C |
| Security Exchange Name | NYSE |
| Market Vectors E T Nsdue March 312020 [Member] | |
| Schedule of Capitalization, Equity [Line Items] | |
| Title of 12(b) Security | Market Vectors ETNs due March 31, 2020 (two issuances) |
| Trading Symbol | URR/DDR |
| Security Exchange Name | NYSEArca |
| Market Vectors E T Nsdue April 302020 [Member] | |
| Schedule of Capitalization, Equity [Line Items] | |
| Title of 12(b) Security | Market Vectors ETNs due April 30, 2020 (two issuances) |
| Trading Symbol | CNY/INR |
| Security Exchange Name | NYSEArca |
| Morgan Stanley Cushing M L P High Income Index E T Nsdue March 212031 [Member] | |
| Schedule of Capitalization, Equity [Line Items] | |
| Title of 12(b) Security | Morgan Stanley Cushing® MLP High Income Index ETNs due March 21, 2031 |
| Trading Symbol | MLPY |
| Security Exchange Name | NYSEArca |