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DERIVATIVE FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS (Details) Note $ in Thousands | 6 Months Ended |
--- | --- | ---
Jun. 30, 2026 USD ($) Bcf | Jun. 30, 2025 USD ($) | Dec. 31, 2025 USD ($) Bcf
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Fair Value Assets, Transfers between Levels | $ 0 | $ 0 |
Long-term Debt, Fair Value | $ 2,500,000 |  | $ 2,500,000
Commodity Option |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Derivative, Nonmonetary Notional Amount | Bcf |  |  | 0.50
Premiums recorded in other current assets on natural gas contracts held |  |  | $ 500
Swap |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Derivative, Nonmonetary Notional Amount | Bcf | 11.70 |  | 5.02
Other Assets |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Assets, Fair Value Disclosure | $ 30,247 |  | $ 30,599
Other Assets | US Treasury Securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Debt Securities, Trading and Available-for-Sale | 8,267 |  | 9,329
Other Assets | Corporate Bond Securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Debt Securities, Trading and Available-for-Sale | 19,103 |  | 18,643
Other Assets | Equity Securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Equity Securities, FV-NI | 2,877 |  | 2,627
Other Current Liabilities | Swap |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Derivative Liability, Subject to Master Netting Arrangement, after Offset | 600 |  | 7,309
Fair Value, Inputs, Level 1 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Assets, Fair Value Disclosure | 11,144 |  | 11,956
Fair Value, Inputs, Level 1 [Member] | Other Assets | US Treasury Securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Debt Securities, Trading and Available-for-Sale | 8,267 |  | 9,329
Fair Value, Inputs, Level 1 [Member] | Other Assets | Corporate Bond Securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Debt Securities, Trading and Available-for-Sale | 0 |  | 0
Fair Value, Inputs, Level 1 [Member] | Other Assets | Equity Securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Equity Securities, FV-NI | 2,877 |  | 2,627
Fair Value, Inputs, Level 1 [Member] | Other Current Liabilities | Swap |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Derivative Liability, Subject to Master Netting Arrangement, before Offset | 0 |  | 0
Fair Value, Inputs, Level 2 [Member] |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Assets, Fair Value Disclosure | 19,103 |  | 18,643
Fair Value, Inputs, Level 2 [Member] | Other Assets | US Treasury Securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Debt Securities, Trading and Available-for-Sale | 0 |  | 0
Fair Value, Inputs, Level 2 [Member] | Other Assets | Corporate Bond Securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Debt Securities, Trading and Available-for-Sale | 19,103 |  | 18,643
Fair Value, Inputs, Level 2 [Member] | Other Assets | Equity Securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Equity Securities, FV-NI | 0 |  | 0
Fair Value, Inputs, Level 2 [Member] | Other Current Liabilities | Swap |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Derivative Liability, Subject to Master Netting Arrangement, before Offset | 624 |  | 7,309
Master Netting Arrangement |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Assets, Fair Value Disclosure | 0 |  | 0
Master Netting Arrangement | Other Assets | US Treasury Securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Debt Securities, Trading and Available-for-Sale | 0 |  | 0
Master Netting Arrangement | Other Assets | Corporate Bond Securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Debt Securities, Trading and Available-for-Sale | 0 |  | 0
Master Netting Arrangement | Other Assets | Equity Securities |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Equity Securities, FV-NI | 0 |  | 0
Master Netting Arrangement | Other Current Liabilities | Swap |  |  |
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] |  |  |
Derivative Liability, Subject to Master Netting Arrangement, Asset Offset | $ (24) |  | $ 0

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Data Type: | na
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