RELATED PARTY TRANSACTIONS - DEMAND FEES (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Sep. 30, 2025
Related Party Transaction [Line Items]
Demand fees payable	$ 640		$ 641
Related Party
Related Party Transaction [Line Items]
Demand fees expense recognized pertaining to related party agreement	1,277	$ 1,718
Demand fees payable	640		641
Related Party | NJNG to Steckman RIdge Affiliate
Related Party Transaction [Line Items]
Demand fees expense recognized pertaining to related party agreement	1,083	1,524
Demand fees payable	540		540
Related Party | NJRES to Steckman Ridge Affiliate
Related Party Transaction [Line Items]
Demand fees expense recognized pertaining to related party agreement	194	$ 194
Demand fees payable	$ 100		$ 101