EMPLOYEE BENEFIT PLANS - EXPECTED BENEFIT PAYMENTS (Details) $ in Thousands	Sep. 30, 2021 USD ($)
Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2022	$ 13,434
2023	14,353
2024	15,294
2025	16,277
2026	17,269
2027 - 2031	101,147
OPEB
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2022	6,936
2023	7,495
2024	8,069
2025	8,735
2026	9,392
2027 - 2031	$ 55,685

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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