Fair Value Measurements (Details) - USD ($) $ in Millions	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Assets:
Marketable debt securities	$ 3,254.2		$ 2,433.1
Samsung Bioepis
Liabilities:
Equity, ownership interest	49.90%
Fair Value, Measurements Recurring
Assets:
Cash equivalents	$ 2,144.9		1,632.2
Marketable equity securities	785.6		1,048.5
Derivative contracts	180.0		80.9
Plan assets for deferred compensation	31.9		33.4
Total	7,591.5		5,228.1
Liabilities:
Derivative contracts	23.3		10.8
Contingent consideration obligations	197.5	$ 202.0	209.1	$ 226.3	$ 226.0	$ 259.8
Total	220.8		219.9
Fair Value, Measurements Recurring | Samsung Bioepis
Assets:
Other current assets, receivable	788.1
Other assets, receivable	406.8
Fair Value, Measurements Recurring | Corporate debt securities
Assets:
Marketable debt securities	1,890.3		1,108.2
Fair Value, Measurements Recurring | Government securities
Assets:
Marketable debt securities	1,156.9		1,192.7
Fair Value, Measurements Recurring | Mortgage and other asset backed securities
Assets:
Marketable debt securities	207.0		132.2
Quoted Prices in Active Markets (Level 1) | Fair Value, Measurements Recurring
Assets:
Cash equivalents	0.0		0.0
Marketable equity securities	668.7		181.7
Derivative contracts	0.0		0.0
Plan assets for deferred compensation	0.0		0.0
Total	668.7		181.7
Liabilities:
Derivative contracts	0.0		0.0
Contingent consideration obligations	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
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	2,144.9		1,632.2
Marketable equity securities	116.9		866.8
Derivative contracts	180.0		80.9
Plan assets for deferred compensation	31.9		33.4
Total	5,727.9		5,046.4
Liabilities:
Derivative contracts	23.3		10.8
Contingent consideration obligations	0.0		0.0
Total	23.3		10.8
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements Recurring | Samsung Bioepis
Assets:
Other current assets, receivable	0.0
Other assets, receivable	0.0
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements Recurring | Corporate debt securities
Assets:
Marketable debt securities	1,890.3		1,108.2
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements Recurring | Government securities
Assets:
Marketable debt securities	1,156.9		1,192.7
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements Recurring | Mortgage and other asset backed securities
Assets:
Marketable debt securities	207.0		132.2
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
Total	1,194.9		0.0
Liabilities:
Derivative contracts	0.0		0.0
Contingent consideration obligations	197.5		209.1
Total	197.5		209.1
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements Recurring | Samsung Bioepis
Assets:
Other current assets, receivable	788.1
Other assets, receivable	406.8
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