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Income Taxes (Details)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Reconciliation between the U.S. federal statutory tax rate and effective tax rate
Statutory rate	21.00%	21.00%
State taxes	0.40%	0.90%
Taxes on foreign earnings	(4.60%)	(2.00%)
Credits and net operating loss utilization	(0.80%)	(0.80%)
Purchased intangible assets	0.30%	0.60%
Denmark assets held for sale	4.30%	0.00%
Effective Tax Rate Reconciliation, GILTI tax	1.90%	1.30%
Permanent items	0.40%	0.40%
Other	(0.20%)	0.20%
Effective tax rate	22.70%	21.60%

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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