REGULATION - ADDITIONAL INFORMATION (Details) - USD ($) $ in Thousands			3 Months Ended
	Dec. 17, 2025	Oct. 31, 2025	Dec. 31, 2025	Dec. 31, 2024
Schedule of Regulatory Filings [Line Items]
Revenues from contracts with customers			$ 440,899	$ 358,953
NJNG
Schedule of Regulatory Filings [Line Items]
Approved rate increase amount	$ 33,100
Base Rate Stipulation
Schedule of Regulatory Filings [Line Items]
Weighted average cost of capital, percentage			7.08%
BPU
Schedule of Regulatory Filings [Line Items]
Approved return on equity, percentage			9.60%
BPU | NJNG
Schedule of Regulatory Filings [Line Items]
Approved rate increase amount	3,300
NJNG
Schedule of Regulatory Filings [Line Items]
Revenues from contracts with customers		$ 38,100
BGSS Balancing
Schedule of Regulatory Filings [Line Items]
Requested rate increase (decrease), amount	6,100
Conservation Incentive Program
Schedule of Regulatory Filings [Line Items]
Requested rate increase (decrease), amount	(26,200)
SAVEGREEN
Schedule of Regulatory Filings [Line Items]
Capital investments approved by the BPU	$ 13,300