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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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