DERIVATIVE INSTRUMENTS - BALANCE SHEET RELATED DISCLOSURES (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Sep. 30, 2021
Fair Value
Derivative assets, current	$ 21,586	$ 35,251
Derivative liabilities, current	45,216	87,145
Derivative assets, noncurrent	4,140	3,403
Derivative liabilities, noncurrent	19,632	13,497
Not Designated as Hedging Instrument
Fair Value
Derivative assets	25,726	38,654
Derivative liabilities	64,848	100,642
Natural Gas Distribution \| Not Designated as Hedging Instrument \| Physical commodity contracts
Fair Value
Derivative assets, current	101	36
Derivative liabilities, current	16	16
Natural Gas Distribution \| Not Designated as Hedging Instrument \| Financial commodity contracts
Fair Value
Derivative assets, current	111	2,046
Derivative liabilities, current	1,887	13
Energy Services \| Not Designated as Hedging Instrument \| Physical commodity contracts
Fair Value
Derivative assets, current	1,853	2,818
Derivative liabilities, current	21,594	24,592
Derivative assets, noncurrent	131	333
Derivative liabilities, noncurrent	19,632	13,237
Energy Services \| Not Designated as Hedging Instrument \| Financial commodity contracts
Fair Value
Derivative assets, current	19,483	30,226
Derivative liabilities, current	21,701	62,521
Derivative assets, noncurrent	4,009	3,068
Derivative liabilities, noncurrent	0	260
Energy Services \| Not Designated as Hedging Instrument \| Foreign currency contracts
Fair Value
Derivative assets, current	38	125
Derivative liabilities, current	18	3
Derivative assets, noncurrent	0	2
Derivative liabilities, noncurrent	$ 0	$ 0

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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