EMPLOYEE BENEFIT PLANS - ESTIMATED SUBSIDY PAYMENTS (Details) $ in Thousands	Sep. 30, 2018 USD ($)
Defined Benefit Plan, Expected Future Prescription Drug Subsidy Receipt [Abstract]
2019	$ 280
2020	316
2021	347
2022	375
2023	417
2024 - 2028	$ 2,787

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Amount of prescription drug subsidy receipts expected after fifth fiscal year following latest fiscal year.

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Amount of prescription drug subsidy receipts expected in next fiscal year following latest fiscal year.

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Amount of prescription drug subsidy receipts expected in fifth fiscal year following latest fiscal year.

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Amount of prescription drug subsidy receipts expected in fourth fiscal year following latest fiscal year.

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Amount of prescription drug subsidy receipts expected in third fiscal year following latest fiscal year.

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Amount of prescription drug subsidy receipts expected in second fiscal year following latest fiscal year.

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