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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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