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Other Commitments And Contingencies (Narrative) (Details) $ in Millions | Mar. 31, 2025 USD ($) Rate | Feb. 03, 2025 USD ($) | Jan. 15, 2025 USD ($) | Dec. 31, 2024 USD ($)
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Other Commitments And Contingencies [Line Items] |  |  |  |
Guaranty Liabilities | $ 465.4 |  |  | $ 1,127.5
Recorded reserves to cover environmental remediation at various sites | $ 90.4 |  |  | 91.8
Wind Power Purchase Agreement, Purchase Percentage | Rate | 100.00% |  |  |
Payments to Acquire Assets, Investing Activities | $ 144.1 | $ 217.6 | $ 336.6 |
Contractual Obligation | $ 61.7 |  |  |
MGP Sites |  |  |  |
Other Commitments And Contingencies [Line Items] |  |  |  |
Number of waste disposal sites identified by program | 51 |  |  |
Liability for Estimated Remediation Costs | $ 83.8 |  |  | $ 86.4
Reasonably possible remediation costs variance from reserve | 16.3 |  |  |
Standby Letters of Credit |  |  |  |
Other Commitments And Contingencies [Line Items] |  |  |  |
Long-term Line of Credit | $ 9.4 |  |  |

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