Inventories (Schedule Of Inventories) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Inventory [Line Items]
Raw materials	$ 13,652	$ 13,328
Work-in process	3,270	3,137
Finished products and components	2,212	2,516
Total	19,134	18,981
Domestic [Member]
Inventory [Line Items]
Raw materials	10,926	10,657
Work-in process	2,403	2,484
Finished products and components	1,284	1,583
Total	14,613	14,724
Foreign [Member]
Inventory [Line Items]
Raw materials	2,726	2,671
Work-in process	867	653
Finished products and components	928	933
Total	$ 4,521	$ 4,257

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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