Asset Retirement Obligations (Changes In Company's Liability For Asset Retirement Obligations) (Details) - USD ($) $ in Millions |
6 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|
Dec. 31, 2024 |
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
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| Beginning Balance | $ 698.6 | |||
| Accretion recorded as a regulatory asset | 38.0 | $ 25.3 | ||
| Additions | 63.3 | 189.9 | ||
| Settlements | (73.0) | (72.5) | ||
| Change in estimated cash flows | 25.4 | 87.5 | ||
| Asset Retirement Obligation | $ 783.2 | 836.9 | 783.2 | $ 553.0 |
| Ending Balance | 698.6 | 781.9 | 698.6 | |
| Assets recorded for asset retirement obligations | $ 88.7 | $ 277.4 | $ 61.1 | |
| Asset Retirement Obligation, Period Increase (Decrease) | $ 48.9 | |||
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- Definition Accretion Recorded As Regulatory Asset Or Liability No definition available.
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- Definition The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of asset retirement obligations incurred during the period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of increase (decrease) in asset retirement obligations. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The increase (decrease) during the reporting period in the carrying amount of asset retirement obligations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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