DEBT - CONTRACTUAL COMMITMENTS (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Finance Leases
2021	$ 54,992
2022	6,004
2023	4,622
2024	5,279
2025	3,396
Thereafter	2,324
Total future lease payments	76,617
Less: Interest component	(2,458)
Total lease liability	74,159	$ 35,400
NJR
Finance Leases
2021	54,992
2022	6,004
2023	4,622
2024	5,279
2025	3,396
Thereafter	2,324
Total future lease payments	76,617
Less: Interest component	(2,458)
Total lease liability	74,159
Clean Energy Ventures
Sale Leaseback Transaction, Net Book Value [Abstract]
2021	12,928
2022	12,926
2023	13,003
2024	12,904
2025	8,985
Thereafter	47,268
Subtotal	108,014
Less: Interest component	(23,052)
Total	$ 84,962

Finance Lease, Liability, To Be Paid, After Year Four

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- Definition

Sale Leaseback Transactions, Contractual Commitments, Minimum Lease Payment

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No definition available.

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- Definition

Sale Leaseback Transactions, Contractual Commitments, Minimum Lease Payment, After Year Five

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- Definition

Sale Leaseback Transactions, Contractual Commitments, Minimum Lease Payment, Interest

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- Definition

Sale Leaseback Transactions, Contractual Commitments, Minimum Lease Payment, Year Five

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- Definition

Sale Leaseback Transactions, Contractual Commitments, Minimum Lease Payment, Year Four

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- Definition

Sale Leaseback Transactions, Contractual Commitments, Minimum Lease Payment, Year One

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- Definition

Sale Leaseback Transactions, Contractual Commitments, Minimum Lease Payment, Year Three

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Sale Leaseback Transactions, Contractual Commitments, Minimum Lease Payment, Year Two

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- Definition

Sale Leaseback Transactions, Contractual Commitments, Present Value Of Future Minimum Lease Payment

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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-Publisher FASB
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-Section 45
-Paragraph 1
-Subparagraph (b)
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Amount of lessee's undiscounted obligation for lease payments for finance lease.

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

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