Note 3 - Balance Sheet Components - Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Property and equipment, gross	$ 72,039	$ 70,218
Less: accumulated depreciation and amortization	(31,030)	(29,420)
Total	41,009	40,798
Computer Equipment [Member]
Property and equipment, gross	10,893	10,880
Software and Software Development Costs [Member]
Property and equipment, gross	4,685	4,690
Furniture and Fixtures [Member]
Property and equipment, gross	2,419	2,395
Leasehold Improvements [Member]
Property and equipment, gross	6,087	6,095
Laboratory and Test Equipment [Member]
Property and equipment, gross	4,974	4,933
Test Equipment [Member]
Property and equipment, gross	23,604	22,980
Construction in Progress [Member]
Property and equipment, gross	$ 19,377	$ 18,245

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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