Inventories (Schedule Of Inventories) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Inventory [Line Items]
Raw materials	$ 13,924	$ 12,861
Work-in process	3,842	951
Finished products and components	1,349	2,565
Total	19,115	16,377
Domestic [Member]
Inventory [Line Items]
Raw materials	11,341	10,379
Work-in process	3,501	736
Finished products and components	1,160	2,375
Total	16,002	13,490
Foreign [Member]
Inventory [Line Items]
Raw materials	2,583	2,482
Work-in process	341	215
Finished products and components	189	190
Total	$ 3,113	$ 2,887

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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