Note 5 - Property and Equipment, Net - Property and Equipment Components (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Property and equipment, gross	$ 164,524	$ 161,073
Less accumulated depreciation	(95,820)	(90,333)
Total property and equipment	68,704	70,740
Equipment [Member]
Property and equipment, gross	124,774	121,716
Office, Software, and Computer Equipment [Member]
Property and equipment, gross	30,578	30,190
Furniture and Fixtures [Member]
Property and equipment, gross	1,572	1,558
Leasehold Improvements [Member]
Property and equipment, gross	$ 7,600	$ 7,609

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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