Income Taxes Components of Deferred Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Components of Deferred Tax Assets
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Allowance for Doubtful Accounts	$ 310	$ 1,000
Deferred Tax Assets, Inventory	1,900	5,230
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Other	7,220	20,350
Deferred Tax Assets, Operating Loss and Credit Carryforwards	6,990	7,290
Deferred Tax Assets, Gross	16,420	33,870
Deferred Tax Assets, Valuation Allowance	(5,520)	(6,400)
Deferred Tax Assets, Net of Valuation Allowance	10,900	27,470
Components of Deferred Tax Liabilities
Deferred Tax Liabilities, Property, Plant and Equipment	(8,770)	(16,380)
Deferred Tax Liabilities, Goodwill and Intangible Assets	(4,940)	(5,350)
Deferred Tax Liabilities, Investment in Foreign Affiliates, Including Withholding Tax	(1,050)	(740)
Deferred Tax Liabilities, Other	(620)	(1,550)
Deferred Tax Liabilities, Gross	(15,380)	(24,020)
Deferred Tax Liabilities, Net	$ (4,480)
Deferred Tax Assets, Net		$ 3,450