Note 2 - Details of Consolidated Balance Sheet Accounts - Prepaid Expenses and Other (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Insurance premiums	$ 4,608	$ 4,054
Contract assets	2,106	2,746
Other	3,971	3,734
Prepaid Expense and Other Assets, Current	27,512	27,320
Parts And Tires Inventory [Member]
Prepaid expenses	6,286	5,427
License Fees Member [Member]
Prepaid expenses	5,557	6,029
Tires In Service [Member]
Prepaid expenses	$ 4,984	$ 5,330

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