DERIVATIVES (Volumes of Outstanding Derivative Contracts) (Details)	Jun. 30, 2023 MMBTU MWh	Dec. 31, 2022 MWh MMBTU
Forwards, Futures and Swaps | Natural Gas (MMBtus)
Derivative [Line Items]
Contract Volume	246,078,190	171,212,813
Forwards, Futures and Swaps | Electricity (MWh)
Derivative [Line Items]
Contract Volume | MWh	9,389,471	10,814,728
Options | Natural Gas (MMBtus)
Derivative [Line Items]
Contract Volume	44,745,000	27,785,000
Options | Electricity (MWh)
Derivative [Line Items]
Contract Volume	277,200	215,600
Congestion revenue rights | Electricity (MWh)
Derivative [Line Items]
Contract Volume | MWh	180,123,433	205,743,505