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Income Taxes (Details 2)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation between the U.S. federal statutory tax rate and effective tax rate
Statutory rate	35.00%	35.00%	35.00%
State taxes	0.80%	0.90%	0.50%
Taxes on foreign earnings	(11.10%)	(9.60%)	(10.00%)
Credits and net operating loss utilization	(0.80%)	(1.40%)	(1.30%)
Purchased intangible assets	1.40%	1.20%	1.00%
Manufacturing deduction	(1.90%)	(1.90%)	(1.80%)
2017 Tax Act	22.90%	0.00%	0.00%
Impairment of ZINBRYTA related tax assets	0.90%	0.00%	0.00%
Permanent items	0.70%	0.50%	0.70%
Other	0.00%	0.40%	0.30%
Effective tax rate	47.90%	25.10%	24.40%

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