Goodwill and Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Changes in Goodwill
Goodwill, January 1			$ 10,082.3	$ 9,734.3
Goodwill, Acquisitions			657.5	3.2
Goodwill, Noncontrolling interests in acquired businesses			10.7	0.0
Goodwill, Contingent purchase price obligations of acquired businesses			0.0	3.3
Goodwill, Dispositions			(5.9)	(118.6)
Goodwill, Foreign currency translation			(98.1)	81.2
Goodwill, June 30	$ 10,646.5	$ 9,703.4	10,646.5	9,703.4
Goodwill, impairment losses			0.0	0.0
Goodwill, accumulated impairment losses	0.0		0.0
Intangible assets:
Intangible assets, Gross Carrying Value	1,380.0		1,380.0		$ 1,230.5
Intangible assets, Accumulated Amortization	(857.3)		(857.3)		(863.6)
Intangible assets, Net Carrying Value	522.7		522.7		366.9
Amortization of intangible assets	26.3	19.3	52.1	38.6
Acquired intangible assets and internally developed strategic platform assets
Intangible assets:
Intangible assets, Gross Carrying Value	1,088.6		1,088.6		902.6
Intangible assets, Accumulated Amortization	(598.5)		(598.5)		(572.9)
Intangible assets, Net Carrying Value	490.1		490.1		329.7
Amortization of intangible assets	21.5	14.7	43.0	29.5
Other purchased and internally developed software
Intangible assets:
Intangible assets, Gross Carrying Value	291.4		291.4		327.9
Intangible assets, Accumulated Amortization	(258.8)		(258.8)		(290.7)
Intangible assets, Net Carrying Value	32.6		32.6		$ 37.2
Amortization of intangible assets	$ 4.8	$ 4.6	$ 9.1	$ 9.1