FAIR VALUE - ADDITIONAL INFORMATION (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Sep. 30, 2025
NJNG
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Finance leases	$ 45,900	$ 33,500
Level 2 \| NJNG
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Finance leases	45,100	32,500
Fair market value \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	2,613,368	2,631,512
Solar Asset Financing \| CEV
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	485,900	471,500
Solar Asset Financing \| Fair market value \| CEV
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, fair value	$ 496,500	$ 481,400

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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+ Details