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Financial Instruments Descriptions (Details) $ in Millions | 6 Months Ended
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Mar. 31, 2018 USD ($) MMcf
General Discussion Of Derivative Instruments And Hedging Activities [Abstract] |
Minimum Hedge Percentage Of Anticipated Heating Season Gas | 25.00%
Maximum Hedge Percentage Of Anticipated Heating Season Gas | 50.00%
Hedge Percentage Of Anticipated Heating Season Gas | 26.00%
Hedge Volume Of Anticipated Heating Season Gas | MMcf | 15,000
Accumulated Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Interest Rate Agreements, Realized Gain (Loss), Net of Tax | $ (49.1)
Interest Rate Hedges, Senior Notes 2019 Issuance [Member] |
Derivative [Line Items] |
Notional Amount of Interest Rate Cash Flow Hedge Derivatives | 450.0
Anticipated Debt Issuance, Amount | $ 450.0
Derivative, Average Forward Interest Rate | 3.78%

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- Definition Net realized gains and losses in accumulated other comprehensive income from interest rate agreements designated and qualifying as the effective portion of cash flow hedges. + References No definition available. + Details
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- Definition Anticipated debt issuance amount of future debt issuance. + References No definition available. + Details
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- Definition Anticipated percentage of heating season gas purchases using financial instruments. + References No definition available. + Details
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- Definition Anticipated volume of heating season gas purchases using financial instruments. + References No definition available. + Details
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- Definition Maximum anticipated percentage of heating season gas purchases hedged using financial instruments. + References No definition available. + Details
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- Definition Minimum anticipated percentage of heating season gas purchases hedged using financial instruments. + References No definition available. + Details
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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Average stated rate on a group of interest rate forward or futures contracts. + 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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- Details
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