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Commitment, Contingencies And Guarantees (Additional Information) (Details) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2024 | Dec. 31, 2023
Loss Contingencies [Line Items] |  |
Accrued liabilities | $ 291.7 | $ 293.3
Regulatory assets | 432.2 | 480.1
Environmental |  |
Loss Contingencies [Line Items] |  |
Regulatory assets | 10.6 | $ 2.9
Manufactured Gas Plant |  |
Loss Contingencies [Line Items] |  |
Insurance Settlements Receivable, Noncurrent | 1.5 |
Site remediation cost | 7.4 |
Accrued liabilities | 11.5 |
Regulatory assets | $ 10.6 |

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