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Financing - Schedule of Short-term Debt and Narrative (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Short-Term Debt [Line Items]
Amount outstanding	$ 126.0		$ 133.8
Revolving Credit Facility | Commercial Paper
Short-Term Debt [Line Items]
Amount outstanding	126.0		133.8
Letters of credit	3.1		3.5
Available capacity	$ 620.9		$ 612.7
Weighted average interest rates	4.26%		4.74%
Maximum amount outstanding (based on daily outstanding balances)	$ 263.6	$ 25.8
Average amount outstanding (based on daily outstanding balances)	$ 115.9	$ 0.6
Weighted average interest rates	4.55%	5.15%

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Available borrowing capacity.

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- Definition

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