Other Financial Statement Data (Schedule Of Inventories) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Balance Sheet Related Disclosures [Abstract]
Raw materials and purchased parts	$ 12,766	$ 11,903
Work in process	3,038	2,459
Finished goods	3,328	4,208
Demonstration inventories, net	1,530	1,701
Total inventories	$ 20,662	$ 20,271

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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