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v3.25.3

Segment Information - Schedule of Segment Profit or Loss (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenue | $ 325,563 | $ 338,033 | $ 995,959 | $ 1,027,437
Operating and Maintenance Expenses | 41,144 | 43,737 | 136,830 | 136,367
Depreciation and Amortization | 29,554 | 27,051 | 88,376 | 79,579
Property Taxes | 4,333 | 3,705 | 12,788 | 11,691
Interest Expense | 11,790 | 11,173 | 35,063 | 31,225
Selling, General, and Administrative Expenses | 17,792 | 18,829 | 56,434 | 55,896
Income Tax (Benefit) Expense | 12,817 | 18,677 | 36,553 | 57,077
Net Income | 78,292 | 85,479 | 224,119 | 246,812
Electric |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenue | 138,597 | 130,380 | 417,048 | 384,696
Manufacturing |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenue | 76,951 | 79,896 | 237,363 | 275,961
Plastics |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenue | 110,015 | 127,757 | 341,548 | 366,780
Operating Segments |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Interest Expense | 11,670 | 11,084 | 34,791 | 30,843
Income Tax (Benefit) Expense | 15,757 | 19,960 | 42,487 | 61,224
Net Income | 74,719 | 85,183 | 220,179 | 245,586
Operating Segments | Electric |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenue | 138,597 | 130,380 | 417,048 | 384,696
Production Fuel and Purchased Power | 34,937 | 25,726 | 111,917 | 87,516
Operating and Maintenance Expenses | 41,144 | 43,737 | 136,830 | 136,367
Depreciation and Amortization | 22,433 | 20,741 | 67,087 | 61,014
Property Taxes | 4,333 | 3,705 | 12,788 | 11,691
Interest Expense | 10,891 | 10,274 | 32,370 | 28,534
Income Tax (Benefit) Expense | (701) | 948 | (9,178) | 723
Other Segment Items | (1,748) | (3,281) | (5,977) | (10,635)
Net Income | 27,308 | 28,530 | 71,211 | 69,486
Operating Segments | Manufacturing |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenue | 76,951 | 79,896 | 237,363 | 275,961
Depreciation and Amortization | 5,411 | 5,199 | 16,357 | 15,199
Interest Expense | 633 | 664 | 1,882 | 1,865
Cost of Goods Sold | 61,283 | 68,360 | 193,108 | 224,595
Selling, General, and Administrative Expenses | 9,978 | 8,853 | 31,071 | 31,667
Income Tax (Benefit) Expense | 1,141 | (154) | 2,371 | 3,563
Other Segment Items | 0 | (1) | 1 | 0
Net Income | 3,916 | 2,174 | 8,930 | 14,271
Operating Segments | Plastics |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Operating Revenue | 110,015 | 127,757 | 341,548 | 366,780
Depreciation and Amortization | 1,636 | 1,086 | 4,771 | 3,293
Interest Expense | 146 | 146 | 539 | 444
Cost of Goods Sold | 44,139 | 47,056 | 131,155 | 129,867
Selling, General, and Administrative Expenses | 6,919 | 6,956 | 20,526 | 17,777
Income Tax (Benefit) Expense | 15,317 | 19,166 | 49,294 | 56,938
Other Segment Items | (1) | (46) | (4) | (75)
Net Income | $ 43,495 | $ 54,479 | $ 140,038 | $ 161,829

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