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Fair Value Measurements - Summary of Assets and Liabilities Recorded at Fair Value (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | --- | ---
Assets: |  |  |
Marketable debt securities | $ 2,179.2 | $ 2,433.1 |
Fair value, measurements, recurring |  |  |
Assets: |  |  |
Cash equivalents | 2,847.6 | 1,632.2 |
Marketable equity securities | 791.1 | 1,048.5 |
Derivative contracts | 63.0 | 80.9 |
Plan assets for deferred compensation | 32.8 | 33.4 |
Total | 7,117.9 | 5,228.1 |
Liabilities: |  |  |
Derivative contracts | 26.0 | 10.8 |
Contingent consideration obligations | 0.0 | 209.1 | $ 259.8
Total | 26.0 | 219.9 |
Fair value, measurements, recurring | Samsung Bioepis |  |  |
Assets: |  |  |
Receivable from Samsung BioLogics | 798.8 |  |
Receivable from Samsung BioLogics | 405.4 |  |
Fair value, measurements, recurring | Corporate debt securities |  |  |
Assets: |  |  |
Marketable debt securities | 1,231.6 | 1,108.2 |
Fair value, measurements, recurring | Government securities |  |  |
Assets: |  |  |
Marketable debt securities | 810.3 | 1,192.7 |
Fair value, measurements, recurring | Mortgage and other asset backed securities |  |  |
Assets: |  |  |
Marketable debt securities | 137.3 | 132.2 |
Quoted Prices in Active Markets (Level 1) | Fair value, measurements, recurring |  |  |
Assets: |  |  |
Cash equivalents | 0.0 | 0.0 |
Marketable equity securities | 791.1 | 181.7 |
Derivative contracts | 0.0 | 0.0 |
Plan assets for deferred compensation | 0.0 | 0.0 |
Total | 791.1 | 181.7 |
Liabilities: |  |  |
Derivative contracts | 0.0 | 0.0 |
Contingent consideration obligations |  | 0.0 |
Total | 0.0 | 0.0 |
Quoted Prices in Active Markets (Level 1) | Fair value, measurements, recurring | Samsung Bioepis |  |  |
Assets: |  |  |
Receivable from Samsung BioLogics | 0.0 |  |
Receivable from Samsung BioLogics | 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 | 2,847.6 | 1,632.2 |
Marketable equity securities | 0.0 | 866.8 |
Derivative contracts | 63.0 | 80.9 |
Plan assets for deferred compensation | 32.8 | 33.4 |
Total | 5,122.6 | 5,046.4 |
Liabilities: |  |  |
Derivative contracts | 26.0 | 10.8 |
Contingent consideration obligations |  | 0.0 |
Total | 26.0 | 10.8 |
Significant Other Observable Inputs (Level 2) | Fair value, measurements, recurring | Samsung Bioepis |  |  |
Assets: |  |  |
Receivable from Samsung BioLogics | 0.0 |  |
Receivable from Samsung BioLogics | 0.0 |  |
Significant Other Observable Inputs (Level 2) | Fair value, measurements, recurring | Corporate debt securities |  |  |
Assets: |  |  |
Marketable debt securities | 1,231.6 | 1,108.2 |
Significant Other Observable Inputs (Level 2) | Fair value, measurements, recurring | Government securities |  |  |
Assets: |  |  |
Marketable debt securities | 810.3 | 1,192.7 |
Significant Other Observable Inputs (Level 2) | Fair value, measurements, recurring | Mortgage and other asset backed securities |  |  |
Assets: |  |  |
Marketable debt securities | 137.3 | 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 | 1,204.2 | 0.0 |
Liabilities: |  |  |
Derivative contracts | 0.0 | 0.0 |
Contingent consideration obligations | 0.0 | 209.1 |
Total | 0.0 | 209.1 |
Significant Unobservable Inputs (Level 3) | Fair value, measurements, recurring | Samsung Bioepis |  |  |
Assets: |  |  |
Receivable from Samsung BioLogics | 798.8 |  |
Receivable from Samsung BioLogics | 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 |

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