Fair Value Measurements (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Assets:
Marketable debt securities		$ 2,179.2
Derivative contracts	$ 3.4
Samsung Bioepis
Liabilities:
Equity, ownership interest	49.90%				49.90%
Fair Value, Measurements Recurring
Assets:
Cash equivalents	$ 1,920.4	2,847.6
Marketable equity securities	413.6	791.1
Derivative contracts	27.8	63.0
Plan assets for deferred compensation	39.0	32.8
Total	2,826.5	7,117.9
Liabilities:
Derivative contracts	37.5	26.0
Contingent consideration obligations			$ 195.4	$ 197.5		$ 209.1
Total	37.5	26.0
Fair Value, Measurements Recurring | Samsung Bioepis
Assets:
Other current assets, receivable	422.3	798.8
Other assets, receivable		405.4
Fair Value, Measurements Recurring | Corporate debt securities
Assets:
Marketable debt securities		1,231.6
Fair Value, Measurements Recurring | Government securities
Assets:
Marketable debt securities		810.3
Fair Value, Measurements Recurring | Mortgage and other asset backed securities
Assets:
Marketable debt securities		137.3
Quoted Prices in Active Markets (Level 1) | Fair Value, Measurements Recurring
Assets:
Cash equivalents	0.0	0.0
Marketable equity securities	413.6	791.1
Derivative contracts	0.0	0.0
Plan assets for deferred compensation	0.0	0.0
Derivative contracts	0.0
Total	413.6	791.1
Liabilities:
Derivative contracts	0.0	0.0
Total	0.0	0.0
Quoted Prices in Active Markets (Level 1) | Fair Value, Measurements Recurring | Samsung Bioepis
Assets:
Other current assets, receivable	0.0	0.0
Other assets, receivable		0.0
Quoted Prices in Active Markets (Level 1) | Fair Value, Measurements Recurring | Corporate debt securities
Assets:
Marketable debt securities		0.0
Quoted Prices in Active Markets (Level 1) | Fair Value, Measurements Recurring | Government securities
Assets:
Marketable debt securities		0.0
Quoted Prices in Active Markets (Level 1) | Fair Value, Measurements Recurring | Mortgage and other asset backed securities
Assets:
Marketable debt securities		0.0
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements Recurring
Assets:
Cash equivalents	1,920.4	2,847.6
Marketable equity securities	0.0	0.0
Derivative contracts	27.8	63.0
Plan assets for deferred compensation	39.0	32.8
Derivative contracts	3.4
Total	1,990.6	5,122.6
Liabilities:
Derivative contracts	37.5	26.0
Total	37.5	26.0
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements Recurring | Samsung Bioepis
Assets:
Other current assets, receivable	0.0	0.0
Other assets, receivable		0.0
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements Recurring | Corporate debt securities
Assets:
Marketable debt securities		1,231.6
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements Recurring | Government securities
Assets:
Marketable debt securities		810.3
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements Recurring | Mortgage and other asset backed securities
Assets:
Marketable debt securities		137.3
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements Recurring
Assets:
Cash equivalents	0.0	0.0
Marketable equity securities	0.0	0.0
Derivative contracts	0.0	0.0
Plan assets for deferred compensation	0.0	0.0
Derivative contracts	0.0
Total	422.3	1,204.2
Liabilities:
Derivative contracts	0.0	0.0
Total	0.0	0.0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements Recurring | Samsung Bioepis
Assets:
Other current assets, receivable	$ 422.3	798.8
Other assets, receivable		405.4
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements Recurring | Corporate debt securities
Assets:
Marketable debt securities		0.0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements Recurring | Government securities
Assets:
Marketable debt securities		0.0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements Recurring | Mortgage and other asset backed securities
Assets:
Marketable debt securities		$ 0.0