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Income Taxes (Details 2)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation between the U.S. federal statutory tax rate and effective tax rate
Statutory rate	21.00%	35.00%	35.00%
State taxes	0.60%	0.80%	0.90%
Taxes on foreign earnings	(1.90%)	(11.10%)	(9.60%)
Credits and net operating loss utilization	(0.90%)	(0.80%)	(1.40%)
Purchased intangible assets	1.20%	1.40%	1.20%
Manufacturing deduction	0.00%	(1.90%)	(1.90%)
2017 Tax Act	2.10%	22.90%	0.00%
GILTI	1.60%	0.00%	0.00%
Impairment of ZINBRYTA related tax assets	0.00%	0.90%	0.00%
Permanent items	0.30%	0.70%	0.50%
Other	0.20%	0.00%	0.40%
Effective tax rate	24.20%	47.90%	25.10%

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