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SEGMENTS OF BUSINESS - Income Loss Before Taxes Reconciliation (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2024 | Dec. 31, 2024 | Dec. 31, 2023
SEGMENTS OF BUSINESS |  |  |
Other Operating Revenue |  | $ 5,419 | $ 5,025
Amortization of Contract Asset |  |  | (26,581)
Depreciation, Depletion and Amortization |  | (65,626) | (67,211)
Asset Impairment | $ (215,100) | (215,136) | 0
Asset Retirement Obligations Accretion |  | (1,628) | (1,804)
Exploration Costs |  | (260) | (904)
Gain (loss) on disposal or abandonment of assets, net |  | 50 | (398)
Interest expense (1) |  | (13,850) | (13,711)
Loss on Extinguishment of Debt |  | (2,790) | (1,491)
Equity Method Investment (Loss) |  | (746) | (552)
Settlement of litigation |  | (2,750) |
Corporate - General and Administrative |  | (11,339) | (10,958)
Corporate - Other Operating and Maintenance Costs |  | (440) | (568)
NET INCOME (LOSS) BEFORE INCOME TAXES |  | (235,542) | 49,258
Electric sales |  |  |
SEGMENTS OF BUSINESS |  |  |
EBITDA Margin |  | 137,283 | 127,812
Coal sales |  |  |
SEGMENTS OF BUSINESS |  |  |
EBITDA Margin |  | (63,729) | 40,599
Operating Segment | Electric Operations |  |  |
SEGMENTS OF BUSINESS |  |  |
EBITDA Margin |  | 72,007 | 58,034
Other Operating Revenue |  | 982 | 414
Amortization of Contract Asset |  |  | (26,581)
Depreciation, Depletion and Amortization |  | (19,290) | (18,739)
Asset Retirement Obligations Accretion |  | (457) | (576)
Interest expense (1) |  | (1,875) | (322)
NET INCOME (LOSS) BEFORE INCOME TAXES |  | 51,367 | 12,230
Operating Segment | Electric Operations | Electric sales |  |  |
SEGMENTS OF BUSINESS |  |  |
EBITDA Margin |  | 72,007 | 58,034
Operating Segment | Coal Operations |  |  |
SEGMENTS OF BUSINESS |  |  |
EBITDA Margin |  | 1,348 | 111,560
Other Operating Revenue |  | 2,756 | 2,936
Depreciation, Depletion and Amortization |  | (46,245) | (48,365)
Asset Impairment |  | (215,136) |
Asset Retirement Obligations Accretion |  | (1,171) | (1,228)
Exploration Costs |  | (260) | (904)
Gain (loss) on disposal or abandonment of assets, net |  | (1,629) | (398)
Interest expense (1) |  | (11,033) | (11,869)
Loss on Extinguishment of Debt |  |  | (1,491)
Settlement of litigation |  | (2,750) |
NET INCOME (LOSS) BEFORE INCOME TAXES |  | (274,120) | 50,241
Operating Segment | Coal Operations | Coal sales |  |  |
SEGMENTS OF BUSINESS |  |  |
EBITDA Margin |  | 1,348 | 111,560
Corporate and Other and Eliminations |  |  |
SEGMENTS OF BUSINESS |  |  |
Other Operating Revenue |  | 1,681 | 1,675
Depreciation, Depletion and Amortization |  | (91) | (107)
Gain (loss) on disposal or abandonment of assets, net |  | 1,679 |
Interest expense (1) |  | (942) | (1,520)
Loss on Extinguishment of Debt |  | (2,790) |
Equity Method Investment (Loss) |  | (746) | (552)
Corporate - General and Administrative |  | (11,339) | (10,958)
Corporate - Other Operating and Maintenance Costs |  | (440) | (568)
NET INCOME (LOSS) BEFORE INCOME TAXES |  | (12,789) | (13,213)
Corporate and Other and Eliminations | Electric sales |  |  |
SEGMENTS OF BUSINESS |  |  |
EBITDA Margin |  | 65,276 | 69,778
Corporate and Other and Eliminations | Coal sales |  |  |
SEGMENTS OF BUSINESS |  |  |
EBITDA Margin |  | $ (65,077) | $ (70,961)

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