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NATURE OF THE BUSINESS (Details) $ in Millions |  | 9 Months Ended
--- | --- | ---
Nov. 25, 2024 USD ($) MW | Jun. 30, 2025 subsidiary
NJR Retail Holdings Corporation |  |
Nature of Business [Line Items] |  |
Number of principal subsidiaries | subsidiary |  | 1
Steckman Ridge |  |
Nature of Business [Line Items] |  |
Ownership percentage |  | 50.00%
Discontinued Operations | Residential Solar Portfolio |  |
Nature of Business [Line Items] |  |
Number of megawatts | MW | 91 |
Proceeds from divestiture of businesses | $ | $ 132.5 |

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