Fair Value Measurements (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Assets:
Marketable debt securities	$ 4,668.5	$ 2,179.2
Derivative contracts	$ 1.3
Samsung Bioepis
Liabilities:
Equity, ownership interest	49.90%			49.90%
Fair Value, Measurements Recurring
Assets:
Cash equivalents	$ 2,262.4	2,847.6
Marketable equity securities	717.0	791.1
Derivative contracts	20.5	63.0
Plan assets for deferred compensation	40.8	32.8
Total	8,125.7	7,117.9
Liabilities:
Derivative contracts	29.1	26.0
Contingent consideration obligations			$ 197.5	$ 202.0	$ 209.1
Total	29.1	26.0
Fair Value, Measurements Recurring | Samsung Bioepis
Assets:
Other current assets, receivable	415.2	798.8
Other assets, receivable		405.4
Fair Value, Measurements Recurring | Corporate debt securities
Assets:
Marketable debt securities	1,831.0	1,231.6
Fair Value, Measurements Recurring | Government securities
Assets:
Marketable debt securities	2,650.3	810.3
Fair Value, Measurements Recurring | Mortgage and other asset backed securities
Assets:
Marketable debt securities	187.2	137.3
Quoted Prices in Active Markets (Level 1) | Fair Value, Measurements Recurring
Assets:
Cash equivalents	0.0	0.0
Marketable equity securities	717.0	791.1
Derivative contracts	0.0	0.0
Plan assets for deferred compensation	0.0	0.0
Derivative contracts	0.0
Total	717.0	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	0.0
Quoted Prices in Active Markets (Level 1) | Fair Value, Measurements Recurring | Government securities
Assets:
Marketable debt securities	0.0	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	0.0
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements Recurring
Assets:
Cash equivalents	2,262.4	2,847.6
Marketable equity securities	0.0	0.0
Derivative contracts	20.5	63.0
Plan assets for deferred compensation	40.8	32.8
Derivative contracts	1.3
Total	6,993.5	5,122.6
Liabilities:
Derivative contracts	29.1	26.0
Total	29.1	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	1,831.0	1,231.6
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements Recurring | Government securities
Assets:
Marketable debt securities	2,650.3	810.3
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements Recurring | Mortgage and other asset backed securities
Assets:
Marketable debt securities	187.2	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	415.2	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	415.2	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	0.0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements Recurring | Government securities
Assets:
Marketable debt securities	0.0	0.0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements Recurring | Mortgage and other asset backed securities
Assets:
Marketable debt securities	$ 0.0	$ 0.0