Note 3 - Balance Sheet Components - Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Property and equipment, gross	$ 50,460	$ 46,056
Less: accumulated depreciation	(22,365)	(20,670)
Total	28,095	25,386
Computer Equipment [Member]
Property and equipment, gross	10,568	10,729
Software and Software Development Costs [Member]
Property and equipment, gross	4,120	3,348
Furniture and Fixtures [Member]
Property and equipment, gross	4,119	3,676
Leasehold Improvements [Member]
Property and equipment, gross	2,002	1,980
Test Equipment [Member]
Property and equipment, gross	14,659	13,796
Construction in Progress [Member]
Property and equipment, gross	$ 14,992	$ 12,527

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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