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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		9 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Income Taxes [Abstract]
Unrecognized tax benefits	$ 4,500		$ 4,500
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	$ 600		$ 600
Effective tax rate	29.70%	25.30%	25.90%	25.00%
Deferred income taxes	$ 11,093		$ 11,093		$ 9,253
Unremitted earnings of foreign subsidiaries	10,400		10,400
Unrecognized deferred tax liability on unremitted earnings of foreign subsidiaries	600		600
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			$ 14,900