Goodwill and Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Changes in Goodwill
Goodwill, January 1	$ 18,641.4	$ 10,677.4
Goodwill, Acquisitions*	118.1	2.4
Goodwill, Noncontrolling interests in acquired businesses	17.0	2.5
Goodwill, Contingent purchase price obligations of acquired businesses	13.5	2.4
Goodwill, Dispositions	(7.8)	(20.6)
Goodwill, Foreign currency translation	(48.3)	117.4
Goodwill, March 31	18,733.9	10,781.5
Goodwill, impairment losses	0.0	0.0
Goodwill, accumulated impairment losses	0.0
Intangible assets:
Intangible assets, Gross Carrying Value	5,959.4		$ 6,004.2
Intangible assets, Accumulated Amortization	(1,014.2)		(903.2)
Intangible assets, Net Carrying Value	4,945.2		5,101.0
Amortization of intangible assets	117.4	25.8
Acquired intangible assets and internally developed strategic platform assets
Intangible assets:
Intangible assets, Gross Carrying Value	5,655.6		5,728.6
Intangible assets, Accumulated Amortization	(768.9)		(660.2)
Intangible assets, Net Carrying Value	4,886.7		5,068.4
Amortization of intangible assets	110.9	21.8
Trade Names
Intangible assets:
Intangible assets, Gross Carrying Value	926.0		929.9
Intangible assets, Accumulated Amortization	(96.4)		(76.5)
Intangible assets, Net Carrying Value	829.6		853.4
Customer Relationships
Intangible assets:
Intangible assets, Gross Carrying Value	4,374.0		4,389.5
Intangible assets, Accumulated Amortization	(578.2)		(504.1)
Intangible assets, Net Carrying Value	3,795.8		3,885.4
Technology and Other
Intangible assets:
Intangible assets, Gross Carrying Value	355.6		409.2
Intangible assets, Accumulated Amortization	(94.3)		(79.6)
Intangible assets, Net Carrying Value	261.3		329.6
Other purchased and internally developed software
Intangible assets:
Intangible assets, Gross Carrying Value	303.8		275.6
Intangible assets, Accumulated Amortization	(245.3)		(243.0)
Intangible assets, Net Carrying Value	58.5		$ 32.6
Amortization of intangible assets	$ 6.5	$ 4.0