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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 |  |  |

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