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REGULATORY LIABILITIES (Details) $ in Thousands | 1 Months Ended | 9 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Jul. 31, 2024 USD ($) | Jul. 31, 2023 USD ($) | Aug. 31, 2022 USD ($) | Sep. 30, 2024 USD ($) Installment Refund | Dec. 31, 2017 USD ($) | Jun. 12, 2024 USD ($) | Dec. 31, 2023 USD ($) | Jan. 31, 2019 USD ($)
REGULATORY LIABILITIES [Abstract] |  |  |  |  |  |  |  |
Litigation settlement amount |  |  |  | $ 10,000 |  |  |  |
Litigation settlement amount received | $ 2,500 | $ 2,500 | $ 2,500 |  |  |  |  |
Litigation settlement, remaining amount |  |  |  | $ 2,500 |  |  |  |
Number of installments | Installment |  |  |  | 3 |  |  |  |
Number of refunds | Refund |  |  |  | 3 |  |  |  |
Federal corporate tax rate |  |  |  | 21.00% | 34.00% |  |  |
Decrease in the net deferred income tax liability |  |  |  |  | $ 24,300 |  |  |
Regulatory Liabilities [Abstract] |  |  |  |  |  |  |  |
Regulatory liabilities |  |  |  | $ 30,622 | $ 22,800 |  | $ 25,676 |
DEPSC [Member] |  |  |  |  |  |  |  |
Regulatory Liabilities [Abstract] |  |  |  |  |  |  |  |
Regulatory liabilities |  |  |  |  |  | $ 4,000 |  | $ 22,200
Regulatory liabilities, amortization period |  |  |  | 49 years 6 months |  | 6 years |  |
Gross-up adjustment |  |  |  |  |  | $ 7,600 |  |
MDPSC [Member] |  |  |  |  |  |  |  |
Regulatory Liabilities [Abstract] |  |  |  |  |  |  |  |
Regulatory liabilities |  |  |  | $ 600 |  |  |  |
Utility Plant Retirement Cost Obligation [Member] |  |  |  |  |  |  |  |
Regulatory Liabilities [Abstract] |  |  |  |  |  |  |  |
Regulatory liabilities |  |  |  | 310 |  |  | 0 |
Deferred Settlement Refunds [Member] |  |  |  |  |  |  |  |
Regulatory Liabilities [Abstract] |  |  |  |  |  |  |  |
Regulatory liabilities |  |  |  | 2,495 |  |  | 4,991 |
Deferred Income Taxes [Member] |  |  |  |  |  |  |  |
Regulatory Liabilities [Abstract] |  |  |  |  |  |  |  |
Regulatory liabilities |  |  |  | $ 27,817 |  |  | $ 20,685 |

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