SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - CAPITALIZED AND DEFERRED INTEREST (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
NJNG
AFUDC:
Debt	$ 5,134	$ 3,710	$ 1,979
Equity	14,599	6,492	5,531
Total	$ 19,733	$ 10,202	$ 7,510
Weighted average interest rate	6.79%	6.35%	5.94%
Adelphia Gateway
AFUDC:
Debt	$ 1,394
Equity	2,454
Total	$ 3,848
Weighted average interest rate	8.28%

Total increase in earnings in the period representing the cost of equity (based on assumed rate of return) and/or borrowed funds (based on interest rate) used to finance construction of regulated assets, which is expected to be recovered through rate adjustments.

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The component of the allowance for funds used during construction during the period based on an assumed rate of return on equity funds used in financing the construction of regulated assets.

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Amount capitalized of allowance for funds used during construction.

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Effective rate, including composite rate, of cost of financing additions to qualifying regulated assets, commonly called allowance for funds used during construction.

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