| Document and Entity Information Document | Sep. 20, 2019 |
| Document Type | 8-K |
| Written Communications | false |
| Amendment Flag | false |
| Entity File Number | 1-34360 |
| Document Period End Date | Sep. 20, 2019 |
| Entity Registrant Name | ENTERGY TEXAS, INC. |
| Entity Tax Identification Number | 61-1435798 |
| Entity Incorporation, State or Country Code | TX |
| Entity Address, Address Line One | 10055 Grogans Mill Road |
| Entity Address, City or Town | The Woodlands |
| Entity Address, State or Province | TX |
| Entity Address, Country | US |
| Entity Address, Postal Zip Code | 77380 |
| City Area Code | 409 |
| Local Phone Number | 9812000 |
| Entity Central Index Key | 0001427437 |
| Entity Emerging Growth Company | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Ex Transition Period | false |
| Five Point Six Two Five Percent Series First Mortgage Bonds Due June Two Thousand Sixty Four [Member] | |
| Title of 12(b) Security | Mortgage Bonds, 5.625% Series due June 2064 |
| Security Exchange Name | NYSE |
| Trading Symbol | EZT |
| 5.375% Series A Preferred Stock, Cumulative, No Par Value [Domain] | |
| Title of 12(b) Security | 5.375% Series A Preferred Stock, Cumulative, No Par Value (Liquidation Value $25 Per Share) |
| Security Exchange Name | NYSE |
| Trading Symbol | ETI |
