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Cash Flow Information (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Supplemental Cash Flow Information [Abstract] |  |  |
Interest paid, net | $ 78,780 | $ 56,916 | $ 54,925
Income taxes paid, net | 41,765 | 62,181 | 76,689
Property, plant and equipment additions in accounts payable | 25,840 | 22,167 | 12,672
Right-of-use assets obtained in exchange for new operating lease liabilities | 15,811 | 20,777 | 14,967
Equity contribution from Centennial related to the Separation | 0 | 0 | 64,724
Equity contribution to MDU Resources for asset/liability transfers related to the Separation | 0 | 0 | (1,537)
MDU Resources’ stock issued in connection with a business combination | 0 | 0 | 383
Accrual for holdback payment related to a business combination | $ 5,686 | $ 0 | $ 0

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