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v3.25.4

Derivative and Hedging Instruments (Details-1) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2025 USD ($) Dth1 MWh MW | Dec. 31, 2024 USD ($) Dth1 MWh MW
Commodity Contracts And Financial Transimission Rights [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Derivative fair value, net |  | $ 1,400 | $ (100)
Commodity Contract [Member] |  |  |
Notional Disclosures [Abstract] |  |  |
Notional amount, energy measure (in MWh) | MWh |  | 224,360 | 307,640
Notional amount, decatherm measure (in Dth) | Dth1 |  | 8,230,000 | 6,285,000
Derivative Fair Values [Abstract] |  |  |
Asset Derivatives, fair value, gross basis |  | $ 814 | $ 1,213
Liability Derivatives, fair value, gross basis |  | 2,565 | 1,261
Collateral posted against derivative positions |  | 0 | 0
Commodity Contract [Member] | Other Current Liabilities [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Asset Derivatives, fair value, gross basis | [1] | 448 | 927
Liability Derivatives, fair value, gross basis | [1] | 2,380 | 1,121
Commodity Contract [Member] | Other Deferred Liabilities and Other [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Asset Derivatives, fair value, gross basis | [1] | 366 | 286
Liability Derivatives, fair value, gross basis | [1] | 185 | 140
Commodity Contract [Member] | Cash Flow Hedging [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Derivative, right to reclaim collateral (receivable) |  | $ 1,800 | $ 100
Financial Transmission Rights [Member] |  |  |
Notional Disclosures [Abstract] |  |  |
Notional amount, power measure (in MW) | MW |  | 2,413 | 2,131
Derivative Fair Values [Abstract] |  |  |
Asset Derivatives, fair value, gross basis |  | $ 337 | $ 108
Collateral posted against derivative positions |  | 0 | 0
Financial Transmission Rights [Member] | Other Current Assets [Member] |  |  |
Derivative Fair Values [Abstract] |  |  |
Asset Derivatives, fair value, gross basis |  | 337 | 108
Liability Derivatives, fair value, gross basis |  | $ 0 | $ 0
Energy Related Commodity Contract [Member] | Cash Flow Hedging [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Maximum term of derivative hedging contract |  | 4 years |
[1] | As of December 31, 2025, and 2024, collateral of $1.8 million and less than $0.1 million, respectively, was posted against and netted with derivative liability positions. The fair value of the derivatives disclosed in this table has not been adjusted for the collateral posted.

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