EMPLOYEE BENEFIT PLANS - EXPECTED BENEFIT PAYMENTS (Details) $ in Thousands	Sep. 30, 2018 USD ($)
Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2019	$ 10,320
2020	11,769
2021	12,399
2022	13,239
2023	14,217
2024 - 2028	85,426
OPEB
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2019	5,450
2020	6,512
2021	7,096
2022	7,810
2023	8,413
2024 - 2028	$ 50,869

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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

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

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

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

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

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