Other Financial Statement Data (Schedule Of Inventories) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]
Raw materials and purchased parts	$ 10,556	$ 9,845
Work in process	2,055	1,837
Finished goods	3,055	2,373
Demonstration inventories, net	1,384	1,525
Total inventories	$ 17,050	$ 15,580

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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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