Sale Leaseback Transaction, Net Proceeds, Financing Activities, Solar

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Sale Leaseback Transaction, Term Of Lease

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Contractual interest rate for funds borrowed, under the debt agreement.

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DEBT - NJR LONG-TERM DEBT (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Stated interest rate	4.01%
Proceeds from sale leaseback transaction - solar	$ 17,673	$ 42,927	$ 0
Clean Energy Ventures
Debt Instrument [Line Items]
Proceeds from sale leaseback transaction - solar	$ 17,700	$ 42,900
NJR \| Unsecured senior note 3.13% \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate	3.13%
Long-term debt	$ 120,000
NJR \| Unsecured senior notes 3.25% \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate	3.25%
Long-term debt	$ 80,000
Minimum \| Clean Energy Ventures
Debt Instrument [Line Items]
Term of lease	5 years
Maximum \| Clean Energy Ventures
Debt Instrument [Line Items]
Term of lease	15 years