Note 4 - Property and Equipment - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Property and equipment, gross	$ 62,523	$ 62,097
Accumulated depreciation	(44,350)	(41,780)
Property and equipment, net	18,173	20,317
Vehicles [Member]
Property and equipment, gross	57,030	57,224
Property, Plant and Equipment, Other Types [Member]
Property and equipment, gross	1,924	1,319
Building and Building Improvements [Member]
Property and equipment, gross	3,191	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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