Note 3 - Balance Sheet Components - Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Property and equipment, gross	$ 60,692	$ 59,800
Less: accumulated depreciation	(24,756)	(24,119)
Total	35,936	35,681
Computer Equipment [Member]
Property and equipment, gross	10,645	10,536
Software and Software Development Costs [Member]
Property and equipment, gross	4,106	4,112
Furniture and Fixtures [Member]
Property and equipment, gross	4,853	4,688
Leasehold Improvements [Member]
Property and equipment, gross	5,020	5,474
Test Equipment [Member]
Property and equipment, gross	15,110	14,697
Construction in Progress [Member]
Property and equipment, gross	$ 20,958	$ 20,293

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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