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DERIVATIVE INSTRUMENTS - BROKER MARGIN DEPOSITS (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Natural Gas Distribution
Derivative [Line Items]
Broker margin - Current assets	$ 5,396	$ 13,525
Energy Services
Derivative [Line Items]
Broker margin - Current assets	$ 50,838	$ 55,919

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- Definition

Amount of other receivables due from broker-dealers or clearing organizations.

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