Components of Gas Inventory (Detail) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
Jun. 30, 2025 |
|---|---|---|---|
| Public Utilities, Inventory [Line Items] | |||
| Weighted average cost inventory amount | $ 0.9 | $ 1.3 | $ 0.7 |
| Liquified Natural Gas | |||
| Public Utilities, Inventory [Line Items] | |||
| Weighted average cost inventory amount | 0.5 | 0.5 | 0.2 |
| Natural Gas | |||
| Public Utilities, Inventory [Line Items] | |||
| Weighted average cost inventory amount | 0.2 | 0.4 | 0.2 |
| Propane | |||
| Public Utilities, Inventory [Line Items] | |||
| Weighted average cost inventory amount | $ 0.2 | $ 0.4 | $ 0.3 |