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Business Segments - Schedule of Other Specified Segment Disclosures (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2026 | Mar. 31, 2025 | Dec. 31, 2025
Segment Reporting Information [Line Items] |  |  |
Accretion of asset retirement obligations | $ 0.9 | $ 0.9 | $ 3.4
Deferred and noncurrent income taxes (benefits) | 9.3 | (1.4) |
Additions to property, plant and equipment | 90.9 | 64.0 |
Operating Segments | Marketing Segment |  |  |
Segment Reporting Information [Line Items] |  |  |
Accretion of asset retirement obligations | 0.9 | 0.9 |
Deferred and noncurrent income taxes (benefits) | 12.7 | (2.0) |
Additions to property, plant and equipment | 86.9 | 60.8 |
Corporate and Other Assets |  |  |
Segment Reporting Information [Line Items] |  |  |
Accretion of asset retirement obligations | 0.0 | 0.0 |
Deferred and noncurrent income taxes (benefits) | (3.4) | 0.6 |
Additions to property, plant and equipment | $ 4.0 | $ 3.2 |

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