Inventories (Schedule Of Inventories) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Inventory [Line Items]
Raw materials	$ 13,894	$ 13,328
Work-in process	3,471	3,137
Finished products and components	518	1,698
Total	17,883	18,163
Domestic [Member]
Inventory [Line Items]
Raw materials	11,579	10,657
Work-in process	3,103	2,484
Finished products and components	405	1,583
Total	15,087	14,724
Foreign [Member]
Inventory [Line Items]
Raw materials	2,315	2,671
Work-in process	368	653
Finished products and components	113	115
Total	$ 2,796	$ 3,439

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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