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Fair Value Measurements (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
Fair Value Measurements (Details Textual) - USD ($)	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%