Other Income (Expense) - (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Other Income And Expenses [Abstract]
Income From Third Party License Fees	$ 144	$ 141	$ 583	$ 612
Foreign Exchange (Losses) Gains, Net	(285)	545	(1,007)	580
Gain (loss) on Fixed Asset Disposals, Net	81	22	680	50
Non-Income Tax Refunds and Other Related Credits	127	130	668	748
Pension and Post Retirement Benefit Costs Non-service Components	(568)	(537)	(1,713)	(3,539)
Other Nonoperating Income	115	47	374	288
Other Nonoperating Expense	(137)	(99)	(216)	(166)
Total Other (Expense) Income, Net	$ (523)	$ 249	$ (631)	$ (1,427)
Property Plant And Equipment Additional Disclosures			Gain on fixed asset disposals, net, during the nine months ended September 30, 2018 includes a $0.6 million gain on the sale of a held-for-sale asset.
Foreign Currency Transactions Description			In addition, foreign exchange (losses) gains, net, during the three and nine months ended September 30, 2018 include both a foreign currency transaction loss of approximately $0.5 million related to hyper-inflationary accounting for the Company’s Argentina subsidiary effective July 1, 2018 and a foreign currency transaction gain of approximately $0.4 million related to the liquidation of an inactive legal entity.

Other income related to non-service pension cost components

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The amount of cash received during the period as refunds for the overpayment of non-income taxes and other related proceeds.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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Amount of expense related to nonoperating activities, classified as other.

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Additional information disclosed pertaining to property, plant and equipment.

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