Regulation and Rates - Schedule of Purchased Gas Adjustment Mechanism (Details) - Subsidiaries - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Mar. 31, 2026 |
Jun. 30, 2026 |
Dec. 31, 2025 |
Dec. 31, 2024 |
|
| Regulation and Rates [Line Items] | ||||
| Purchased gas adjustment receivable | $ (46,842) | $ (65,931) | $ (58,657) | |
| Purchased Gas Adjustment | ||||
| Regulation and Rates [Line Items] | ||||
| Purchased natural gas costs | $ 397,465 | 221,993 | ||
| Purchased natural gas costs, recoverable | (399,347) | (201,346) | ||
| Purchased natural gas adjustment, interest | $ (5,392) | $ (1,558) |