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Financing - Schedule of Short-term Debt and Narrative (Details) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Dec. 31, 2023
Short-Term Debt [Line Items] |  |  |
Amount outstanding | $ 17.5 |  | $ 0.0
Revolving Credit Facility | Commercial Paper |  |  |
Short-Term Debt [Line Items] |  |  |
Amount outstanding | 17.5 |  | 0.0
Letters of Credit | 3.5 |  | 3.7
Available capacity | $ 729.0 |  | $ 746.3
Weighted average interest rates | 4.93% |  |
Maximum amount outstanding (based on daily outstanding balances) | $ 25.8 | $ 548.7 |
Average amount outstanding (based on daily outstanding balances) | $ 0.6 | $ 109.2 |
Weighted average interest rates | 5.15% | 4.91% |

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