Fair Value (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Assets:
Short-term investments	$ 0.0	$ 60.7
Liabilities:
Contingent purchase price obligations	229.5	115.0
Carrying Amount
Assets:
Cash and cash equivalents	4,432.0	4,281.8
Short-term investments	0.0	60.7
Marketable equity securities	0.9	0.9
Non-marketable equity securities	6.7	5.6
Liabilities:
Short-term debt	10.9	16.9
Foreign currency derivatives	0.0	0.1
Cross currency swaps - net investment hedge	6.6
Contingent purchase price obligations	229.5	115.0
Long-term debt	5,639.6	5,577.2
Fair Value
Assets:
Cash and cash equivalents	4,432.0	4,281.8
Short-term investments	0.0	60.7
Marketable equity securities	0.9	0.9
Non-marketable equity securities	6.7	5.6
Liabilities:
Short-term debt	10.9	16.9
Foreign currency derivatives	0.0	0.1
Cross currency swaps - net investment hedge	6.6	16.5
Contingent purchase price obligations	229.5	115.0
Long-term debt	5,237.8	4,993.4
Contingent purchase price obligations
Changes in Contingent Purchase Price Obligations [Roll Forward]
January 1	115.0	167.1
Acquisitions	217.4	13.3
Revaluation and interest	(36.1)	(26.0)
Payments	(67.7)	(32.7)
Foreign currency translation	0.9	(6.7)
December 31	229.5	115.0
Fair Value, Recurring [Member]
Assets:
Cash and cash equivalents	4,432.0	4,281.8
Short-term investments		60.7
Marketable equity securities	0.9	0.9
Liabilities:
Foreign currency derivatives		0.1
Cross currency swaps - net investment hedge	6.6	16.5
Contingent purchase price obligations	229.5	115.0
Fair Value, Recurring [Member] | Level 1
Assets:
Cash and cash equivalents	4,432.0	4,281.8
Marketable equity securities	0.9	0.9
Fair Value, Recurring [Member] | Level 2
Assets:
Short-term investments		60.7
Liabilities:
Foreign currency derivatives		0.1
Cross currency swaps - net investment hedge	6.6	16.5
Fair Value, Recurring [Member] | Level 3
Liabilities:
Contingent purchase price obligations	$ 229.5	$ 115.0