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DERIVATIVE INSTRUMENTS - BROKER MARGIN DEPOSITS (Details) - USD ($) $ in Thousands | Mar. 31, 2018 | Sep. 30, 2017
--- | --- | ---
Natural Gas Distribution |  |
Derivative [Line Items] |  |
Broker margin - Current assets | $ 3,612 | $ 2,661
Energy Services |  |
Derivative [Line Items] |  |
Broker margin - Current assets | $ 56,358 | $ 23,166

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- Details
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- Details
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