Other Financial Statement Data (Schedule Of Inventories) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Balance Sheet Related Disclosures [Abstract]
Raw materials and purchased parts	$ 15,174	$ 11,903
Work in process	1,732	2,459
Finished goods	2,323	4,208
Demonstration inventories, net	1,448	1,701
Total inventories	$ 20,677	$ 20,271

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