Note 5 - Property and Equipment (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Depreciation, Total	$ 49,800	$ 60,400
Gain (Loss) on Disposition of Property Plant Equipment, Total	3,799	7,706
Finance Lease, Right-of-Use Asset, before Accumulated Amortization	45,500	50,200
Finance Lease, Right-of-Use Asset, Accumulated Amortization	22,300	20,800
Finance Lease, Right-of-Use Asset, Amortization	$ 3,620	$ 4,080
Revenue Equipment [Member] | Minimum [Member]
Capital Leases of Lessee, Term of Contract (Month)	48 months	48 months
Revenue Equipment [Member] | Maximum [Member]
Capital Leases of Lessee, Term of Contract (Month)	84 months	84 months
Net in Depreciation and Amortization Expense [Member]
Gain (Loss) on Disposition of Property Plant Equipment, Total		$ 7,700