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v3.25.0.1

Segment Information - Schedule of Segment Profit or Loss (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | $ 1,330,548 | $ 1,349,166 | $ 1,460,209
Operating and Maintenance Expenses | 190,422 | 191,263 | 181,378
Depreciation and Amortization | 107,121 | 97,954 | 92,597
Property Taxes | 15,662 | 16,614 | 17,742
Interest Expense | 41,815 | 37,677 | 36,016
Selling, General, and Administrative Expenses | 80,065 | 72,663 | 69,718
Income Tax Expense (Benefit) | 65,230 | 69,298 | 73,351
Net Income | 301,662 | 294,191 | 284,184
Electric |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 524,515 | 528,359 | 549,699
Manufacturing |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 342,592 | 402,781 | 397,983
Plastics |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 463,441 | 418,026 | 512,527
Operating Segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Interest Expense | 41,322 | 36,761 | 35,331
Income Tax Expense (Benefit) | 71,995 | 73,104 | 79,074
Net Income | 305,391 | 293,626 | 296,298
Operating Segments | Electric |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 524,515 | 528,359 | 549,699
Production Fuel and Purchased Power | 122,506 | 138,631 | 165,391
Operating and Maintenance Expenses | 190,422 | 191,263 | 181,378
Depreciation and Amortization | 82,136 | 75,330 | 72,050
Property Taxes | 15,662 | 16,614 | 17,742
Interest Expense | 38,216 | 33,864 | 31,950
Income Tax Expense (Benefit) | (1,544) | 1,648 | 5,065
Other Segment Items | (13,846) | (13,415) | (3,851)
Net Income | 90,963 | 84,424 | 79,974
Operating Segments | Manufacturing |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 342,592 | 402,781 | 397,983
Depreciation and Amortization | 20,393 | 18,495 | 16,202
Interest Expense | 2,516 | 2,295 | 2,796
Cost of Goods Sold | 283,390 | 324,245 | 327,228
Selling, General, and Administrative Expenses | 40,110 | 49,396 | 41,690
Income Tax Expense (Benefit) | 2,895 | 5,390 | 5,321
Other Segment Items | 0 | 1 | (2)
Net Income | 13,681 | 21,454 | 20,950
Operating Segments | Plastics |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating Revenue | 463,441 | 418,026 | 512,527
Depreciation and Amortization | 4,494 | 4,027 | 4,205
Interest Expense | 590 | 602 | 585
Cost of Goods Sold | 166,628 | 143,521 | 227,571
Selling, General, and Administrative Expenses | 24,908 | 20,103 | 20,378
Income Tax Expense (Benefit) | 70,644 | 66,066 | 68,688
Other Segment Items | (76) | (14) | (69)
Net Income | $ 200,747 | $ 187,748 | $ 195,374

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