EMPLOYEE BENEFIT PLANS - ESTIMATED SUBSIDY PAYMENTS (Details) $ in Thousands	Sep. 30, 2017 USD ($)
Defined Benefit Plan, Expected Future Prescription Drug Subsidy Receipt [Abstract]
2018	$ 262
2019	283
2020	311
2021	342
2022	373
2023 - 2027	$ 2,574

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

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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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