RETIREMENT PLANS - FAIR VALUE (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Sep. 30, 2016
Plan assets
Entity's stock included in plan assets	$ 4
Pension plan assets at the fair value
Fair value measurements	9,098	$ 8,195
Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	$ 9,098	$ 8,195
Cash and cash equivalents
Entity's year-end target allocation, by asset category, and the actual asset allocations
Actual asset allocation	1.00%	7.00%
Cash and cash equivalents \| Maximum
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	30.00%
Cash and cash equivalents \| Minimum
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	0.00%
Fixed income securities
Entity's year-end target allocation, by asset category, and the actual asset allocations
Actual asset allocation	31.00%	23.00%
Fixed income securities \| Maximum
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	60.00%
Fixed income securities \| Minimum
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	20.00%
Equity securities
Entity's year-end target allocation, by asset category, and the actual asset allocations
Actual asset allocation	68.00%	70.00%
Equity securities \| Maximum
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	70.00%
Equity securities \| Minimum
Entity's year-end target allocation, by asset category, and the actual asset allocations
Target allocation	30.00%
Cash
Pension plan assets at the fair value
Fair value measurements	$ 124	$ 571
Cash \| Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	124	571
Certificates of Deposit [Member]
Pension plan assets at the fair value
Fair value measurements	496
Certificates of Deposit [Member] \| Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	496
Corporate bonds
Pension plan assets at the fair value
Fair value measurements	210	316
Corporate bonds \| Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	210	316
Fixed income exchange-traded funds
Pension plan assets at the fair value
Fair value measurements	2,036	1,414
Fixed income exchange-traded funds \| Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	2,036	1,414
Preferred securities
Pension plan assets at the fair value
Fair value measurements	51	184
Preferred securities \| Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	51	184
Equity securities exchange- traded funds
Pension plan assets at the fair value
Fair value measurements	553	818
Equity securities exchange- traded funds \| Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	553	818
Equities
Pension plan assets at the fair value
Fair value measurements	5,628	4,892
Equities \| Quoted Prices in Active Markets (Level 1)
Pension plan assets at the fair value
Fair value measurements	$ 5,628	$ 4,892

The amount of employer securities or securities of parties related to the employer that are included in plan assets.

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

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Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ 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 (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ 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 (d)(5)(i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2446-114920

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