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Short-Term and Long-Term Debt - Schedule of Short-Term and Long-Term Debt (Details) - USD ($) $ in Millions | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Principal |  |
Short-Term Debt | $ 17.2 | $ 111.5
Long-Term Debt | 1,780.1 | 1,687.9
Total Debt | 1,797.3 | 1,799.4
Unamortized Debt Issuance Costs |  |
Short-Term Debt | 0.0 | (0.1)
Long-Term Debt | (7.7) | (8.0)
Total Debt | (7.7) | (8.1)
Total |  |
Short-Term Debt | 17.2 | 111.4
Long-Term Debt | 1,772.4 | 1,679.9
Total Debt | $ 1,789.6 | $ 1,791.3

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