Additional Financial Statement Information (Other) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Foreign exchange loss	$ (1,638)	$ (279)	$ (724)
Interest income	622	506	167
Pension expense	(643)	(1,682)	(863)
Other	958	(41)	1,337
Other nonoperating income (expense)	$ (701)	$ (1,496)	$ (83)

Amount of net periodic benefit cost (credit) for defined benefit plan.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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