Note 3 - Revenue Recognition (Details Textual) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Revenue from Contract with Customer, Excluding Assessed Tax	$ 159,806	$ 166,100	$ 187,561	$ 102,601	$ 152,945	$ 127,636	$ 157,530	$ 103,342	$ 616,068	$ 541,453	$ 480,154
Contract with Customer, Asset, after Allowance for Credit Loss, Total	$ 0				$ 0				0	0
Fleet Upfit Sales [Member]
Revenue from Contract with Customer, Excluding Assessed Tax									$ 136	$ 373	$ 542