DERIVATIVE INSTRUMENTS - BALANCE SHEET RELATED DISCLOSURES (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Fair Value
Derivative assets, current	$ 24,635	$ 35,251
Derivative liability, Current	49,848	87,145
Derivative assets, noncurrent	6,385	3,403
Derivative liabilities, noncurrent	14,191	13,497
Not Designated as Hedging Instrument
Fair Value
Derivative assets	31,020	38,654
Derivative liabilities	64,039	100,642
Natural Gas Distribution \| Not Designated as Hedging Instrument \| Physical commodity contracts
Fair Value
Derivative assets, current	252	36
Derivative liability, Current	11	16
Natural Gas Distribution \| Not Designated as Hedging Instrument \| Financial commodity contracts
Fair Value
Derivative assets, current	85	2,046
Derivative liability, Current	6,281	13
Energy Services \| Not Designated as Hedging Instrument \| Physical commodity contracts
Fair Value
Derivative assets, current	9,857	2,818
Derivative liability, Current	17,051	24,592
Derivative assets, noncurrent	376	333
Derivative liabilities, noncurrent	13,561	13,237
Energy Services \| Not Designated as Hedging Instrument \| Financial commodity contracts
Fair Value
Derivative assets, current	14,423	30,226
Derivative liability, Current	26,488	62,521
Derivative assets, noncurrent	6,009	3,068
Derivative liabilities, noncurrent	630	260
Energy Services \| Not Designated as Hedging Instrument \| Foreign currency contracts
Fair Value
Derivative assets, current	18	125
Derivative liability, Current	17	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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