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Public Utilities, Weighted Average Cost Of Capital, Percentage

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Schedule of Regulatory Filings [Line Items]

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Amount of public utility's approved rate increase (decrease) by regulatory agency.

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Percentage of public utility's approved return on equity.

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Amount of public utility's requested rate increase (decrease) with regulatory agency.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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REGULATION - ADDITIONAL INFORMATION (Details) - USD ($) $ in Thousands				3 Months Ended		6 Months Ended
	Mar. 18, 2026	Dec. 17, 2025	Oct. 31, 2025	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Schedule of Regulatory Filings [Line Items]
Revenues from contracts with customers				$ 641,350	$ 569,199	$ 1,082,249	$ 928,152
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
RAC
Schedule of Regulatory Filings [Line Items]
Capital investments approved by the BPU	$ (800)
NJCEP
Schedule of Regulatory Filings [Line Items]
Capital investments approved by the BPU	$ (5,200)