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Fair Value Measurements (Details Textual) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |
Asset impairment charges | $ 0 |  | $ 0 |  |
Contingent consideration obligations | 202,500,000 |  | 202,500,000 |  | $ 197,700,000
Contingent consideration impairment | (10,000,000.0) | $ 20,000,000.0 | (5,500,000) | $ 8,500,000 |
Future payment | $ 0 | $ 0 | $ 0 | $ 0 |
2.900% Senior Notes due 2020 |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |
Senior notes interest rate | 2.90% |  | 2.90% |  |
3.625% Senior Notes due 2022 |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |
Senior notes interest rate | 3.625% |  | 3.625% |  |
4.050% Senior Notes due 2025 |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |
Senior notes interest rate | 4.05% |  | 4.05% |  |
5.200% Senior Notes due 2045 |  |  |  |  |
Business Acquisition, Contingent Consideration [Line Items] |  |  |  |  |
Senior notes interest rate | 5.20% |  | 5.20% |  |

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