Regulatory and Rate Matters - Schedule of Interim Distribution Rate Increases (Details) - Texas-New Mexico Power Company - Periodic Distribution Rate Adjustment - USD ($) $ in Millions |
Dec. 29, 2025 |
Jun. 29, 2025 |
Nov. 17, 2024 |
Jul. 28, 2024 |
|---|---|---|---|---|
| Public Utilities, General Disclosures [Line Items] | ||||
| Approved Increase in Rate Base | $ 18.9 | $ 176.6 | $ 43.7 | $ 205.9 |
| Annual Increase in Revenue | $ 1.8 | $ 25.0 | $ 7.7 | $ 15.6 |