RELATED PARTY TRANSACTIONS - DEMAND FEES (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Sep. 30, 2023
Related Party Transaction [Line Items]
Demand fees payable	$ 857		$ 859
Related Party
Related Party Transaction [Line Items]
Demand fees expense recognized pertaining to related party agreement	1,879	$ 1,827
Demand fees payable	857		859
Related Party | NJNG to Steckman RIdge Affiliate
Related Party Transaction [Line Items]
Demand fees expense recognized pertaining to related party agreement	1,655	1,655
Demand fees payable	775		775
Related Party | NJRES to Steckman Ridge Affiliate
Related Party Transaction [Line Items]
Demand fees expense recognized pertaining to related party agreement	224	$ 172
Demand fees payable	$ 82		$ 84