Note 6 - Property and Equipment - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Property and equipment, gross	$ 69,004	$ 65,252
Less accumulated depreciation and amortization	(23,835)	(22,037)
Property and equipment, net	45,169	43,215
Land and Land Improvements [Member]
Property and equipment, gross	14,524	14,318
Building and Building Improvements [Member]
Property and equipment, gross	36,379	34,721
Machinery and Equipment [Member]
Property and equipment, gross	9,577	9,151
Office Equipment [Member]
Property and equipment, gross	6,455	6,301
Vehicles [Member]
Property and equipment, gross	472	467
Construction in Progress [Member]
Property and equipment, gross	$ 1,597	$ 294

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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