Note 3 - Property and Equipment - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property and equipment, gross	$ 61,968	$ 62,097
Accumulated depreciation	(42,933)	(41,780)
Property and equipment, net	19,035	20,317
Vehicles [Member]
Property and equipment, gross	57,090	57,224
Property, Plant and Equipment, Other Types [Member]
Property and equipment, gross	1,324	1,319
Building and Building Improvements [Member]
Property and equipment, gross	3,176	3,176
Land [Member]
Property and equipment, gross	$ 378	$ 378

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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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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