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DERIVATIVE INSTRUMENTS - BROKER MARGIN DEPOSITS (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Sep. 30, 2018
--- | --- | ---
Natural Gas Distribution |  |
Derivative [Line Items] |  |
Broker margin - Current assets | $ 1,460 | $ 2,038
Energy Services |  |
Derivative [Line Items] |  |
Broker margin - Current assets | $ 43,367 | $ 51,681

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- Details
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- Details
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