Fair Value (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Carrying Amount
Assets:
Cash and cash equivalents	$ 3,406.5		$ 4,339.4
Marketable equity securities	0.9		0.9
Non-marketable equity securities	30.6		36.8
Cross currency swaps - net investment hedge	0.0		9.3
Liabilities:
Short-term debt	24.1		21.3
Foreign currency derivatives	0.0		0.1
Cross currency swaps - net investment hedge	8.8		0.0
Contingent purchase price obligations	204.8		220.1
Long-Term Debt	6,275.2		6,035.3
Fair Value
Assets:
Cash and cash equivalents	3,406.5		4,339.4
Marketable equity securities	0.9		0.9
Non-marketable equity securities	30.6		36.8
Cross currency swaps - net investment hedge	0.0		9.3
Liabilities:
Short-term debt	24.1		21.3
Foreign currency derivatives	0.0		0.1
Cross currency swaps - net investment hedge	8.8		0.0
Contingent purchase price obligations	204.8		220.1
Long-Term Debt	6,036.3		5,664.9
Contingent purchase price obligations
Changes in Contingent Purchase Price Obligations [Roll Forward]
January 1	220.1	$ 229.5
Acquisitions	27.6	28.5
Revaluation and interest	4.5	1.9
Payments	(47.9)	(23.6)
Foreign currency translation	0.5	0.1
September 30	204.8	$ 236.4
Fair Value, Recurring [Member]
Assets:
Cash and cash equivalents	3,406.5		4,339.4
Marketable equity securities	0.9		0.9
Cross currency swaps - net investment hedge			9.3
Liabilities:
Foreign currency derivatives			0.1
Cross currency swaps - net investment hedge	8.8
Contingent purchase price obligations	204.8		220.1
Fair Value, Recurring [Member] | Level 1
Assets:
Cash and cash equivalents	3,406.5		4,339.4
Marketable equity securities	0.9		0.9
Fair Value, Recurring [Member] | Level 2
Assets:
Cross currency swaps - net investment hedge			9.3
Liabilities:
Foreign currency derivatives			0.1
Cross currency swaps - net investment hedge	8.8
Fair Value, Recurring [Member] | Level 3
Liabilities:
Contingent purchase price obligations	$ 204.8		$ 220.1