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Fair Value Measurement - Level 3 Fair Value Measurements (Details) - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 | Dec. 31, 2020
Level 3 Fair Value Measurements [Roll Forward] |  |
Balance, beginning of period | $ 3.6 | $ 3.3
Increase in fair value recorded in earnings | 0.9 | 1.2
Payments | (1.0) | (0.9)
Balance, end of period | $ 3.5 | $ 3.6
Sales Projections | Minimum |  |
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items] |  |
Business combination, contingent consideration, measurement input | 10.00% |
Sales Projections | Maximum |  |
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items] |  |
Business combination, contingent consideration, measurement input | 50.00% |
Sales Projections | Weighted Average |  |
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items] |  |
Business combination, contingent consideration, measurement input | 40.00% |
Probabilities of Successful FDA Approval | Minimum |  |
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items] |  |
Business combination, contingent consideration, measurement input | 19.00% |
Probabilities of Successful FDA Approval | Maximum |  |
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items] |  |
Business combination, contingent consideration, measurement input | 100.00% |
Probabilities of Successful Execution of Agreement | Minimum |  |
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items] |  |
Business combination, contingent consideration, measurement input | 25.00% |
Probabilities of Successful Execution of Agreement | Maximum |  |
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items] |  |
Business combination, contingent consideration, measurement input | 100.00% |
Measurement Input, Discount Rate |  |
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items] |  |
Business combination, contingent consideration, measurement input | 19.00% |

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- Definition Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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