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v3.25.1

Segment Information - Schedule of Segment Profit or Loss (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Segment Reporting Information [Line Items] |  |
Operating Revenue | $ 337,353 | $ 347,068
Operating and Maintenance Expenses | 48,881 | 47,977
Depreciation and Amortization | 29,375 | 25,897
Property Taxes | 4,228 | 4,367
Interest Expense | 11,553 | 9,850
Selling, General, and Administrative Expenses | 21,292 | 18,914
Income Tax (Benefit) Expense | 10,085 | 17,808
Net Income | 68,099 | 74,338
Electric |  |
Segment Reporting Information [Line Items] |  |
Operating Revenue | 149,720 | 141,488
Manufacturing |  |
Segment Reporting Information [Line Items] |  |
Operating Revenue | 81,685 | 99,380
Plastics |  |
Segment Reporting Information [Line Items] |  |
Operating Revenue | 105,948 | 106,200
Operating Segments |  |
Segment Reporting Information [Line Items] |  |
Interest Expense | 11,426 | 9,672
Income Tax (Benefit) Expense | 11,557 | 19,202
Net Income | 69,679 | 74,471
Operating Segments | Electric |  |
Segment Reporting Information [Line Items] |  |
Operating Revenue | 149,720 | 141,488
Production Fuel and Purchased Power | 45,191 | 40,215
Operating and Maintenance Expenses | 48,881 | 47,977
Depreciation and Amortization | 22,377 | 19,887
Property Taxes | 4,228 | 4,367
Interest Expense | 10,657 | 8,954
Income Tax (Benefit) Expense | (4,008) | 1,175
Other Segment Items | (2,314) | (3,557)
Net Income | 24,708 | 22,470
Operating Segments | Manufacturing |  |
Segment Reporting Information [Line Items] |  |
Operating Revenue | 81,685 | 99,380
Depreciation and Amortization | 5,424 | 4,912
Interest Expense | 623 | 571
Cost of Goods Sold | 68,516 | 80,615
Selling, General, and Administrative Expenses | 10,743 | 11,352
Income Tax (Benefit) Expense | 272 | 1,582
Other Segment Items | (1) | (1)
Net Income | 1,532 | 5,261
Operating Segments | Plastics |  |
Segment Reporting Information [Line Items] |  |
Operating Revenue | 105,948 | 106,200
Depreciation and Amortization | 1,546 | 1,075
Interest Expense | 146 | 147
Cost of Goods Sold | 40,087 | 37,810
Selling, General, and Administrative Expenses | 6,985 | 5,085
Income Tax (Benefit) Expense | 15,293 | 16,445
Other Segment Items | (2) | (27)
Net Income | $ 43,439 | $ 46,740

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