DERIVATIVE INSTRUMENTS - VOLUME (Details) - Bcf	9 Months Ended	12 Months Ended
	Jun. 30, 2023	Sep. 30, 2022
Natural Gas Distribution | Long | Futures
Derivative [Line Items]
Notional amount	26.0	30.5
Natural Gas Distribution | Long | Physical Commodity
Derivative [Line Items]
Notional amount	3.7	6.8
Energy Services | Long | Physical Commodity
Derivative [Line Items]
Notional amount	2.1	2.7
Energy Services | Short | Futures
Derivative [Line Items]
Notional amount	(14.2)	(0.7)