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DEBT - SALE-LEASEBACKS (Details) $ in Thousands | 12 Months Ended
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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

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- Definition Lessee Leasing Arrangements, Capital Leases, Term of Contract + References No definition available. + Details
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- Definition Sale Leaseback Transaction, Lease Renewal Term + References No definition available. + Details
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- Definition Sale Leaseback Transaction, Lease Renewal Term, Maximum + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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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 + Details
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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 + Details
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