Acquisitions Cash Paid for Acquisitions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Oct. 03, 2022
Cash Paid for Acquisitions [Abstract]
Cost of investment: current-year acquisitions	$ 0.0	$ 5.8	$ 235.4
Cost of investment: prior-year acquisitions	9.0	16.6	9.3
Less: net cash acquired	0.0	3.2	3.2
Total cost of investment	9.0	19.2	241.5
Operating payments	0.3	2.7	9.6
Total cash paid for acquisitions	9.3	21.9	251.1
Acquisitions, net of cash acquired		2.6
Payments for previous acquisition, financing cash flows	9.0	12.9	$ 9.3
Acquired finite-lived intangible assets related to acquisitions	$ 0.0	$ 8.5
Business Acquisition, Percentage of Voting Interests Acquired				83.90%