Income Taxes Effective tax rate (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Income Tax Disclosure [Abstract]
Effective Income Tax Rate	5.00%	19.00%	10.00%	14.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%	21.00%
Share-based Payment Arrangement, Expense, Tax Benefit	$ 100,000	$ 300,000	$ 3,600,000	$ 7,700,000
Discretetaxbenefitcontingentconsiderationrevaluation	$ 700,000	$ 11,400,000	$ 1,100,000
GILTIchangeinestimatetaxexpense				2,200,000
IPrepatriationtaxbenefit				3,800,000
Returntoprovisionadjustments				$ 3,800,000