DERIVATIVE INSTRUMENTS - OFFSETTING OF ASSETS AND LIABILITIES (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Sep. 30, 2021
Energy Services
Derivative assets:
Amounts Presented on Balance Sheets	$ 30,683	$ 36,572
Offsetting Derivative Instruments	(12,619)	(34,191)
Financial Collateral Received/Pledged	(200)	19,832
Net Amounts	17,864	22,213
Derivative liabilities:
Amounts Presented on Balance Sheets	57,747	100,613
Offsetting Derivative Instruments	(12,619)	(34,191)
Financial Collateral Received/Pledged	0	0
Net Amounts	45,128	66,422
Energy Services \| Physical commodity contracts
Derivative assets:
Amounts Presented on Balance Sheets	10,233	3,151
Offsetting Derivative Instruments	(404)	(894)
Financial Collateral Received/Pledged	(200)	(700)
Net Amounts	9,629	1,557
Derivative liabilities:
Amounts Presented on Balance Sheets	30,612	37,829
Offsetting Derivative Instruments	(404)	(894)
Financial Collateral Received/Pledged	0	0
Net Amounts	30,208	36,935
Energy Services \| Financial commodity contracts
Derivative assets:
Amounts Presented on Balance Sheets	20,432	33,294
Offsetting Derivative Instruments	(12,198)	(33,294)
Financial Collateral Received/Pledged	0	20,532
Net Amounts	8,234	20,532
Derivative liabilities:
Amounts Presented on Balance Sheets	27,118	62,781
Offsetting Derivative Instruments	(12,198)	(33,294)
Financial Collateral Received/Pledged	0	0
Net Amounts	14,920	29,487
Energy Services \| Foreign currency contracts
Derivative assets:
Amounts Presented on Balance Sheets	18	127
Offsetting Derivative Instruments	(17)	(3)
Financial Collateral Received/Pledged	0	0
Net Amounts	1	124
Derivative liabilities:
Amounts Presented on Balance Sheets	17	3
Offsetting Derivative Instruments	(17)	(3)
Financial Collateral Received/Pledged		0
Net Amounts	0	0
Natural Gas Distribution
Derivative assets:
Amounts Presented on Balance Sheets	337	2,082
Offsetting Derivative Instruments	(85)	(21)
Financial Collateral Received/Pledged	0	0
Net Amounts	252	2,061
Derivative liabilities:
Amounts Presented on Balance Sheets	6,292	29
Offsetting Derivative Instruments	(85)	(21)
Financial Collateral Received/Pledged	0	0
Net Amounts	6,207	8
Natural Gas Distribution \| Physical commodity contracts
Derivative assets:
Amounts Presented on Balance Sheets	252	36
Offsetting Derivative Instruments	0	(8)
Financial Collateral Received/Pledged	0	0
Net Amounts	252	28
Derivative liabilities:
Amounts Presented on Balance Sheets	11	16
Offsetting Derivative Instruments	0	(8)
Financial Collateral Received/Pledged	0	0
Net Amounts	11	8
Natural Gas Distribution \| Financial commodity contracts
Derivative assets:
Amounts Presented on Balance Sheets	85	2,046
Offsetting Derivative Instruments	(85)	(13)
Financial Collateral Received/Pledged	0	0
Net Amounts	0	2,033
Derivative liabilities:
Amounts Presented on Balance Sheets	6,281	13
Offsetting Derivative Instruments	(85)	(13)
Financial Collateral Received/Pledged	0	0
Net Amounts	$ 6,196	$ 0

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