Note F - Segment Information - Segment Revenue Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Revenue, before fuel surcharges	$ 182,592	$ 221,724
Freight Transportation Service [Member]
Revenue, before fuel surcharges	$ 160,969	$ 193,454
Freight Transportation Service [Member] \| Revenue Benchmark [Member] \| Product Concentration Risk [Member]
Revenue, before fuel surcharges, percentage	100.00%	100.00%
Truckload Services [Member] \| Freight Transportation Service [Member]
Revenue, before fuel surcharges	$ 102,200	$ 125,198
Truckload Services [Member] \| Freight Transportation Service [Member] \| Revenue Benchmark [Member] \| Product Concentration Risk [Member]
Revenue, before fuel surcharges, percentage	63.50%	64.70%
Brokerage and Logistics Services [Member] \| Freight Transportation Service [Member]
Revenue, before fuel surcharges	$ 58,769	$ 68,256
Brokerage and Logistics Services [Member] \| Freight Transportation Service [Member] \| Revenue Benchmark [Member] \| Product Concentration Risk [Member]
Revenue, before fuel surcharges, percentage	36.50%	35.30%

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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+ Details