| Document and Entity Information Document | Apr. 14, 2022 |
| Written Communications | false |
| Title of 12(b) Security | Mortgage Bonds, 4.90% Series due October 2066 |
| Amendment Flag | false |
| Entity File Number | 1-31508 |
| Document Type | 8-K |
| Document Period End Date | Apr. 14, 2022 |
| Entity Registrant Name | Entergy Mississippi, LLC |
| Entity Tax Identification Number | 83-1950019 |
| Entity Incorporation, State or Country Code | TX |
| Entity Address, Address Line One | 308 East Peal Street |
| Entity Address, City or Town | Jackson |
| Entity Address, State or Province | MS |
| Entity Address, Country | US |
| Entity Address, Postal Zip Code | 39201 |
| City Area Code | 601 |
| Local Phone Number | 368-5000 |
| Entity Central Index Key | 0000066901 |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Trading Symbol | EMP |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
