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Other Commitments And Contingencies (Narrative) (Details) $ in Millions | Jun. 30, 2023 USD ($) Rate | Dec. 31, 2022 USD ($)
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Other Commitments And Contingencies [Line Items] |  |
Guaranty Liabilities | $ 841.6 | $ 841.6
Estimated Maximum Disgorgement Exposure | 7.7 |
Recorded reserves to cover environmental remediation at various sites | $ 84.5 | 86.5
Wind Power Purchase Agreement, Purchase Percentage | Rate | 100.00% |
MGP Sites |  |
Other Commitments And Contingencies [Line Items] |  |
Number of waste disposal sites identified by program | 53 |
Liability for Estimated Remediation Costs | $ 79.5 | $ 81.0
Reasonably possible remediation costs variance from reserve | 15.0 |
Standby Letters of Credit |  |
Other Commitments And Contingencies [Line Items] |  |
Long-term Line of Credit | $ 10.2 |

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