Amount of research credits potentially disallowed on income tax return for the applicable tax year..

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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A credit or adjustment for government or taxing authority authorized decrease in taxes owed as a result of meeting certain tax policy conditions.

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Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Income Taxes [Abstract]
Unrecognized tax benefits	$ 3,400		$ 3,400
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	$ 500		$ 500
Effective tax rate	26.00%	26.20%	23.40%	24.90%
Deferred income taxes	$ 11,257		$ 11,257		$ 9,253
Unremitted earnings of foreign subsidiaries	10,100		10,100
Unrecognized deferred tax liability on unremitted earnings of foreign subsidiaries	500		500
Internal Revenue Service (IRS) \| Tax Years 2011, 2012 and 2013
Income Taxes [Abstract]
Disallowed research tax credits being litigated	$ 5,700		5,700
Internal Revenue Service (IRS) \| Tax Years 2011 to Date
Income Taxes [Abstract]
Income Tax Credits and Adjustments			$ 11,500