Components of Energy Supply Obligations (Detail) - USD ($) $ in Millions |
Jun. 30, 2025 |
Dec. 31, 2024 |
Jun. 30, 2024 |
---|---|---|---|
Contractual Obligation [Line Items] | |||
Energy Supply Obligations-Current | $ 11.1 | $ 10.0 | $ 8.6 |
Exchange Gas Obligation | |||
Contractual Obligation [Line Items] | |||
Energy Supply Obligations-Current | 8.7 | 6.0 | 5.5 |
Renewable Energy Portfolio Standards | |||
Contractual Obligation [Line Items] | |||
Energy Supply Obligations-Current | $ 2.4 | $ 4.0 | $ 3.1 |