Business Segments - Schedule of Other Specified Segment Disclosures (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
Dec. 31, 2025 |
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| Segment Reporting [Line Items] | |||||
| Accretion of asset retirement obligations | $ 0.9 | $ 0.8 | $ 1.8 | $ 1.7 | $ 3.4 |
| Deferred and noncurrent income taxes (benefits) | 6.4 | 1.3 | 15.7 | (0.1) | |
| Additions to property, plant and equipment | 128.3 | 112.6 | 219.2 | 176.6 | |
| Operating Segments | Marketing Segment | |||||
| Segment Reporting [Line Items] | |||||
| Accretion of asset retirement obligations | 0.9 | 0.8 | 1.8 | 1.7 | |
| Deferred and noncurrent income taxes (benefits) | 8.3 | 1.8 | 21.0 | (0.2) | |
| Additions to property, plant and equipment | 122.4 | 108.0 | 209.3 | 168.8 | |
| Corporate and Other Assets | |||||
| Segment Reporting [Line Items] | |||||
| Accretion of asset retirement obligations | 0.0 | 0.0 | 0.0 | 0.0 | |
| Deferred and noncurrent income taxes (benefits) | (1.9) | (0.5) | (5.3) | 0.1 | |
| Additions to property, plant and equipment | $ 5.9 | $ 4.6 | $ 9.9 | $ 7.8 | |
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- Definition Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of deferred income tax expense (benefit) and income tax credits. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of expenditure for addition to long-lived asset included in determination of segment asset by chief operating decision maker (CODM) or otherwise regularly provided to CODM. Long-lived asset excludes financial instrument, long-term customer relationship of financial institution, mortgage and other servicing rights, deferred policy acquisition cost, and deferred tax asset. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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