Note 10 - Commitments and Contingencies (Details Textual)	Sep. 30, 2022 USD ($)
Lessee, Operating Lease, Liability, to be Paid, Total	$ 459,000
Capital Addition Purchase Commitments [Member] | Revenue Equipment [Member]
Purchase Obligation, to be Paid, Remainder of Fiscal Year	19,800,000
Purchase Obligation, to be Paid, Year One	47,300,000
Purchase Obligation, to be Paid, Year Two	13,000,000.0
Capital Addition Purchase Commitments [Member] | Building Construction [Member]
Purchase Obligation, to be Paid, Remainder of Fiscal Year	$ 6,000,000.0