INVESTMENTS IN EQUITY INVESTEES (Details) $ in Thousands		6 Months Ended	12 Months Ended
Jan. 30, 2020 phase mi	Mar. 31, 2021 USD ($) mi	Sep. 30, 2020 USD ($)
Schedule of Equity Method Investments [Line Items]
Investments in equity investees		$ 214,521	$ 208,375
Deferred tax gross up		$ 7,600	4,600
PennEast \| NJR Pipeline
Schedule of Equity Method Investments [Line Items]
Ownership percentage		20.00%
Steckman Ridge
Schedule of Equity Method Investments [Line Items]
Investments in equity investees		$ 111,435	112,378
Total outstanding principal balance of loans		$ 70,400	70,400
Ownership percentage		50.00%
PennEast
Schedule of Equity Method Investments [Line Items]
Investments in equity investees		$ 103,086	$ 95,997
Ownership percentage		20.00%
Construction plan, project area (in miles) \| mi	68	120
Number of phases \| phase	2

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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