Derivative Instruments - Fair Values of Derivative Contracts Recorded in Condensed Consolidated Balance Sheet (Detail) - USD ($) $ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
||||
|---|---|---|---|---|---|---|
| Derivatives, Fair Value [Line Items] | ||||||
| Energy Marketing Contracts Assets, Current | $ 0.8 | $ 0.0 | ||||
| Energy Marketing Contract Liabilities, Current | 0.2 | 0.8 | ||||
| Energy Marketing Contract Liabilities, Total | [1] | 0.7 | 1.4 | |||
| Energy Marketing Contracts Assets, Total | [2] | 0.9 | 0.0 | |||
| Propane Swap Agreement [Member] | ||||||
| Derivatives, Fair Value [Line Items] | ||||||
| Energy Marketing Contracts Assets, Current | 0.9 | 0.0 | ||||
| Energy Marketing Contract Liabilities, Current | 0.0 | 0.7 | ||||
| Interest Rate Swap [Member] | Derivatives designated as hedging instrument [Member] | ||||||
| Derivatives, Fair Value [Line Items] | ||||||
| Energy Marketing Contract Liabilities, Current | $ 0.7 | $ 0.7 | ||||
| ||||||