DERIVATIVE INSTRUMENTS - BALANCE SHEET RELATED DISCLOSURES (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Sep. 30, 2022
Fair Value
Derivative assets, current	$ 25,658	$ 24,635
Derivative liability, current	24,183	49,848
Derivative assets, noncurrent	1,640	6,385
Derivative liabilities, noncurrent	17,368	14,191
Not Designated as Hedging Instrument
Fair Value
Derivative assets	27,298	31,020
Derivative liabilities	41,551	64,039
Natural Gas Distribution \| Not Designated as Hedging Instrument \| Physical commodity contracts
Fair Value
Derivative assets, current	100	252
Derivative liability, current	24	11
Natural Gas Distribution \| Not Designated as Hedging Instrument \| Financial commodity contracts
Fair Value
Derivative assets, current	0	85
Derivative liability, current	0	6,281
Energy Services \| Not Designated as Hedging Instrument \| Physical commodity contracts
Fair Value
Derivative assets, current	4,262	9,857
Derivative liability, current	10,140	17,051
Derivative assets, noncurrent	4	376
Derivative liabilities, noncurrent	17,368	13,561
Energy Services \| Not Designated as Hedging Instrument \| Financial commodity contracts
Fair Value
Derivative assets, current	21,296	14,423
Derivative liability, current	14,019	26,488
Derivative assets, noncurrent	1,636	6,009
Derivative liabilities, noncurrent	0	630
Energy Services \| Not Designated as Hedging Instrument \| Foreign currency contracts
Fair Value
Derivative assets, current	0	18
Derivative liability, current	$ 0	$ 17

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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