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FAIR VALUE - DEBT (Details) - USD ($) $ in Thousands | Jun. 30, 2018 | Sep. 30, 2017
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Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Capital leases | $ 40,100 | $ 39,700
Level 2 | Carrying Value |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt, fair value | 1,197,045 | 1,097,045
Level 2 | Fair market value |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Long-term debt, fair value | 1,193,741 | 1,107,676
Natural Gas Distribution |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt issuance costs, gross | 6,600 | 6,300
NJR |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt issuance costs, gross | $ 1,300 | $ 770

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- Definition Capital Leased Assets, Fair Value Disclosure + References No definition available. + Details
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- Definition Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399 + 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 The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References No definition available. + Details
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