Note 9 - Leases (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Impairment of Long-Lived Assets to be Disposed of	$ 0	$ 26,569
Revenue Equipment Rentals and Purchased Transportation	331,685	222,705
Property, Plant, and Equipment, Net [Member]
Operating Lease, Right-of-Use Asset	35,700	37,400
Finance Lease, Right-of-Use Asset, after Accumulated Amortization, Total	$ 23,200	29,400
Leased Office Facility [Member]
Impairment of Long-Lived Assets to be Disposed of		2,200
Revenue Equipment Rentals and Purchased Transportation		$ 800