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Operations and Significant Accounting Policies - Other Current Liabilities (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Organization, Consolidation and Presentation of Financial Statements [Abstract] |  |
Customer Deposits | $ 7.8 | $ 7.4
PSAs | 5.9 | 6.0
Provision for Interim Rate Refund | 23.0 | 0.0
Manufactured Gas Plant | 0.1 | 0.8
Other | 81.1 | 77.7
Total Other Current Liabilities | $ 117.9 | $ 91.9

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