Fair Value Measurements (Details Textual) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Business Acquisition, Contingent Consideration [Line Items]
Asset impairment charges	$ 0	$ 0
Contingent consideration obligations	173,200,000	173,200,000	$ 197,700,000
Reduction in contingent consideration	$ 61,200,000	$ 61,200,000
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%

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of increase (decrease) in the value of right to a contingent consideration asset.

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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

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Contractual interest rate for funds borrowed, under the debt agreement.

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