DEBT - SALE-LEASEBACKS (Details) $ in Thousands	12 Months Ended
Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)
Debt Instrument [Line Items]
Proceeds from sale-leaseback transaction	$ 9,587	$ 7,107	$ 7,216
Natural Gas Distribution
Debt Instrument [Line Items]
Sale leaseback transaction, lease term	25 years 6 months
Sale leaseback transaction, lease renewal term	5 years
Sale leaseback transaction, maximum lease renewal term (as a percent)	4
Proceeds from sale-leaseback transaction	$ 9,587	7,100	7,200
Sale leaseback transaction, other payments required	$ 2,400	$ 1,900	$ 768

Lessee Leasing Arrangements, Capital Leases, Term of Contract

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- Definition

Sale Leaseback Transaction, Lease Renewal Term

+ References

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- Definition

Sale Leaseback Transaction, Lease Renewal Term, Maximum

+ References

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- Definition

Amount of cash inflow after closing and debt issuance costs received by a seller-lessee in a sale-leaseback recognized in financing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 55
-Paragraph 51
-URI http://asc.fasb.org/extlink&oid=82846721&loc=d3e51840-112757

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 55
-Paragraph 50
-URI http://asc.fasb.org/extlink&oid=82846721&loc=d3e51831-112757

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 55
-Paragraph 52
-URI http://asc.fasb.org/extlink&oid=82846721&loc=d3e51843-112757

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- Definition

Other amounts the seller-lessee is required to pay under the terms of the transaction involving the sale of property to another party and lease of the property back to the seller, including reimbursements for such items, as utilities, taxes, insurance and common area maintenance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77913982&loc=d3e50796-112755

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84164451&loc=d3e36991-112694

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