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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - DEMAND FEES (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2015
Demand fees | $ 206.6 | $ 218.8 | $ 211.1
Energy Services |  |  |
Demand fees | 126.4 | 141.0 | 130.6
Natural Gas Distribution |  |  |
Demand fees | $ 80.2 | $ 77.8 | $ 80.5
Minimum |  |  |
Storage and pipeline capacity, contract term | 1 year |  |
Maximum |  |  |
Storage and pipeline capacity, contract term | 10 years |  |

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- Definition Demand fees incurred associated with contracts for storage and/or pipeline capacity and recognized as a component of gas purchases. + References No definition available. + Details
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- Definition Storage and Pipeline Capacity, Term of Contract + References No definition available. + Details
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- Details
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- Details
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- Details
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- Details
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