Income Taxes - Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Income Tax Provision at the Federal Statutory Tax Rate	$ 17,458	$ 21,229	$ 29,403
Unremitted Earnings	7,857	0	0
Transition tax	(3,118)	18,388	0
Revaluation of deferred tax assets and liabilities	0	4,470	0
Global Intangible Low Taxed Income	1,211	0	0
Foreign Derived Intangible Income	(1,034)	0	0
Non-deductible acquisition expenses	1,019	4,779	696
Share-based compensation	259	(1,419)	0
Differences in Tax Rates on Foreign Earnings and Remittances	1,081	(2,663)	(2,862)
Foreign Dividends	0	0	2,939
Excess Foreign Tax Credit Utilization	0	(2,761)	(5,493)
Research and Development Activities Credit Utilization	(230)	(235)	(238)
Uncertain Tax Positions	(79)	(651)	(833)
U.S. Domestic Production Activities Deduction	0	(1,155)	(875)
State Income Tax Provisions, Net	196	569	357
Non-deductible Entertainment and Business Meals Expense	415	248	238
Miscellaneous Items, Net	15	854	(106)
Income Tax Expense (Benefit), Total	$ 25,050	$ 41,653	$ 23,226