Note 4 - Balance Sheet Components - Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Property and equipment, gross	$ 61,920	$ 59,800
Less: accumulated depreciation and amortization	(26,074)	(24,119)
Total	35,846	35,681
Computer Equipment [Member]
Property and equipment, gross	10,660	10,536
Software and Software Development Costs [Member]
Property and equipment, gross	4,214	4,112
Furniture and Fixtures [Member]
Property and equipment, gross	4,836	4,688
Leasehold Improvements [Member]
Property and equipment, gross	5,996	5,474
Test Equipment [Member]
Property and equipment, gross	21,952	14,697
Construction in Progress [Member]
Property and equipment, gross	$ 14,262	$ 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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