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Note 6 - Restructuring and Cost Savings Initiatives - Other Restructuring Gains and Charges (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019
Gain on sale of Hutchins, TX terminal		$ 4,946	$ 1,386
Total	$ (22)
Highway Services and Dedicated [Member] \| Gain on Disposition of Property and Equipment, Net [Member]
Gain on sale of Hutchins, TX terminal	5,712
Abandonment	1,048
Highway Services and Dedicated [Member] \| Revenue Equipment Rentals and Purchased Transportation [Member]
Abandonment	825
Highway Services and Dedicated [Member] \| General Supplies and Expenses [Member]
Contract exit costs and restructuring related costs and professional fees	695
Highway Services, Dedicated, and Managed Freight [Member] \| Salaries Wages And Related Expenses [Member]
Employee separation costs (1)	1,791
Dedicated and Managed Freight [Member] \| Depreciation and Amortization [Member]
Change in useful life/abandonment of intangible assets	$ 1,331