Goodwill and Other Intangible Assets - Schedule of Goodwill and Other Intangible Assets Rollforward (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Goodwill
Goodwill, beginning balance	$ 439.2	$ 168.8
Acquisitions of businesses	690.8	270.4
Measurement period adjustments	23.1	0.0
Attribution of acquisition date fair value estimates between goodwill and other intangible assets	(235.6)	0.0
Impairments	(9.1)
Dispositions	(294.3)	0.0
Goodwill, ending balance	614.1	439.2	$ 168.8
Other Intangible Assets
Other intangible assets (excluding goodwill), beginning balance	281.1	201.8
Acquisition of businesses	0.0	101.0
Acquisitions of intangible assets	0.0	0.3
Measurement period adjustments	0.0	0.0
Attribution of acquisition date fair value estimates between goodwill and other intangible assets	235.6	0.0
Amortization	(28.4)	(22.0)	(7.2)
Impairments	(0.5)
Dispositions of businesses	(81.7)	0.0
Other intangible assets (excluding goodwill), ending balance	406.1	281.1	201.8
Total Goodwill and Other Intangible Assets
Total goodwill and other intangible assets, beginning balance	720.3	370.6
Acquisition of businesses	690.8	371.4
Acquisition of intangible assets	0.0	0.3
Measurement period adjustments	23.1	0.0
Attribution of acquisition date fair value estimates between goodwill and other intangible assets (1)	0.0	0.0
Amortization	(28.4)	(22.0)	(7.2)
Goodwill and intangible asset impairment	(9.6)
Disposition of businesses	(376.0)	0.0
Total goodwill and other intangible assets, ending balance	$ 1,020.2	$ 720.3	$ 370.6