SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - NATURAL GAS IN STORAGE (Details) $ in Thousands	Sep. 30, 2022 USD ($) Bcf	Sep. 30, 2021 USD ($) Bcf
Inventory [Line Items]
Natural Gas in Storage, value | $	$ 273,644	$ 193,606
Natural Gas in Storage, Bcf | Bcf	39,800,000	46,400,000
Natural Gas Distribution
Inventory [Line Items]
Natural Gas in Storage, value | $	$ 191,175	$ 115,824
Natural Gas in Storage, Bcf | Bcf	29,000,000.0	27,600,000
Energy Services
Inventory [Line Items]
Natural Gas in Storage, value | $	$ 82,469	$ 77,782
Natural Gas in Storage, Bcf | Bcf	10,800,000	18,800,000