Inventories (Schedule Of Inventories) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Inventory [Line Items]
Raw materials	$ 12,861	$ 13,328
Work-in process	951	3,137
Finished products and components	2,565	1,698
Total	16,377	18,163
Domestic [Member]
Inventory [Line Items]
Raw materials	10,379	10,657
Work-in process	736	2,484
Finished products and components	2,375	1,583
Total	13,490	14,724
Foreign [Member]
Inventory [Line Items]
Raw materials	2,482	2,671
Work-in process	215	653
Finished products and components	190	115
Total	$ 2,887	$ 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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