EMPLOYEE BENEFIT PLANS - AMOUNTS EXPECTED TO BE RECOGNIZED IN NET PERIODIC BENEFIT COST (Details) $ in Thousands	12 Months Ended
Sep. 30, 2023 USD ($)
Pension
Regulatory Assets
Net actuarial loss (gain)	$ 815
Prior service cost	62
Total	877
Accumulated Other Comprehensive Income (Loss)
Net actuarial loss (gain)	(12)
Prior service cost	0
Total	(12)
OPEB
Regulatory Assets
Net actuarial loss (gain)	667
Prior service cost	0
Total	667
Accumulated Other Comprehensive Income (Loss)
Net actuarial loss (gain)	661
Prior service cost	0
Total	$ 661

Defined Benefit Plan Amortization Of Net Gain (Loss) Regulated Assets

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Defined Benefit Plan Amortization Of Net Prior Service Cost Credit Regulatory Assets

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- Definition

Defined Benefit Plan Amounts That Will Be Amortized From Regulatory Assets In Next Fiscal Year

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Defined Benefit Plan, Amount to be Amortized from Regulatory Assets [Abstract]

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Amount of cost (credit) included in accumulated other comprehensive (income) loss expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

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