Variable Interest Entities - Narrative (Details) $ in Millions |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
|
Sep. 30, 2026
USD ($)
MW
|
Sep. 30, 2025
USD ($)
|
Sep. 30, 2026
USD ($)
MW
|
Sep. 30, 2025
USD ($)
|
May 31, 2025
MW
|
|
| San Juan Generating Station | Coal supply | |||||
| Variable Interest Entity [Line Items] | |||||
| Cash used to support bank letter or credit arrangement | $ 19.3 | $ 19.3 | |||
| PNM | Valencia | |||||
| Variable Interest Entity [Line Items] | |||||
| Payment for fixed costs | 5.3 | $ 5.2 | 15.7 | $ 15.1 | |
| Payment for variable costs | $ 1.5 | $ 1.7 | $ 2.9 | $ 3.1 | |
| Long-term contract option to purchase, ownership percentage (up to) | 50.00% | ||||
| Long-term contract option to purchase, purchase price - percentage of adjusted NBV | 50.00% | ||||
| Long-term contract option to purchase, purchase price - percentage of FMV | 50.00% | ||||
| PNM | Purchased through May 2028 | Valencia | |||||
| Variable Interest Entity [Line Items] | |||||
| Number of megawatts purchased (in megawatts) | MW | 155 | 155 | 167 | ||