Discontinued Operations (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Gain on sale of discontinued operation	$ 12,800	$ 12,807
PCB business [Member]
Gross proceeds from sale of discontinued operations	32,000
Acquisition expense deducted from gross proceeds from sale of discontinued operations	$ 2,000

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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