Note 1 - Summary of Significant Accounting Policies (Details Textual) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended								12 Months Ended			42 Months Ended
	Jul. 08, 2020 USD ($)	Apr. 30, 2018 USD ($)	Dec. 31, 2020 USD ($) $ / shares	Sep. 30, 2020 USD ($) $ / shares	Jun. 30, 2020 USD ($) $ / shares	Mar. 31, 2020 USD ($) $ / shares	Dec. 31, 2019 USD ($) $ / shares	Sep. 30, 2019 USD ($) $ / shares	Jun. 30, 2019 USD ($) $ / shares	Mar. 31, 2019 USD ($) $ / shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Mar. 31, 2018 USD ($)	Apr. 01, 2024 USD ($)	Mar. 21, 2021 USD ($)	Apr. 01, 2020 USD ($)
Number of Reportable Segments											4
Insurance Policy Primary Occurence Limit			$ 9,000								$ 9,000
Insurance Policy Excess Coverage			1,000								1,000
Insurance Policy, Fixed Premium Expense																	$ 500
Proceeds from Divestiture of Businesses											108,375	$ 0	$ 0
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax, Total											(40,431)	(0)	(0)
Contract with Customer, Liability, Revenue Recognized											1,200	800	1,300
Accounts Receivable, after Allowance for Credit Loss, Total			91,300				$ 81,200				91,300	81,200	97,500
Depreciation, Depletion and Amortization, Nonproduction, Total											65,472	80,502	75,843
Net Income (Loss) Attributable to Parent, Total			$ (25,663)	$ 7,501	$ (22,343)	$ (2,213)	$ 1,162	$ (3,189)	$ 6,071	$ 4,433	$ (42,718)	$ 8,477	$ 42,503
Earnings Per Share, Diluted, Total (in dollars per share) | $ / shares			$ (1.50)	$ 0.43	$ (1.31)	$ (0.12)	$ 0.06	$ (0.17)	$ 0.33	$ 0.24	$ (2.46)	$ 0.45	$ 2.30
Impairment of Long-Lived Assets Held-for-use											$ 26,569	$ 0	$ 0
Finite-Lived Intangible Asset, Useful Life (Year)											105 months	128 months
Insurance Policy, Reinstatement Charges											$ 1,000
Workers Compensation Self Insurance Per Claim											1,300
Cargo Losses Purchased Coverage per Claim											300
Employee Annual Insuarnce Deductible Per Claim											$ 400
Physical Damage Coverage											100.00%
Drivers Advances And Other Receivables Net Of Allowance			$ 13,624				$ 8,507				$ 13,624	$ 8,507
Liability for Claims and Claims Adjustment Expense, Single Loss Limit		$ 9,000
Liability for Claims and Claims Adjustment Expense, Aggregate Limit per Policy Year		18,000
Liability for Claims and Claims Adjustment Expense, Aggregate Three Year Limit		30,000
Auto Policy Release Premium Refund		$ 14,000												$ 7,300
Interest Costs Capitalized											$ 100	$ 100
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures, Total (in shares) | shares											195,000	200,000	129,000
Employee Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares) | shares											70,000
Share-based Payment Arrangement, Option [Member]
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture, Total (in shares) | shares											70,000	0	0
Receivables from Insurers [Member]
Drivers Advances And Other Receivables Net Of Allowance			0				300				$ 0	$ 300
Insurance Settlements Receivable, Current			7,400				0				7,400	0
Insurance Settlements Receivable, Noncurrent			$ 24,400				2,100				$ 24,400	$ 2,100
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)											3 years
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)											15 years
Tractors [Member]
Property, Plant and Equipment, Useful Life (Year)											5 years
Tractors [Member] | Minimum [Member]
Property, Plant and Equipment, Salvage Value, Percentage			10.00%								10.00%
Tractors [Member] | Maximum [Member]
Property, Plant and Equipment, Salvage Value, Percentage			35.00%								35.00%
Refrigerated Trailers [Member]
Property, Plant and Equipment, Useful Life (Year)											7 years
Dry Van Trailers [Member]
Property, Plant and Equipment, Useful Life (Year)											10 years
Dry Van Trailers [Member] | Minimum [Member]
Property, Plant and Equipment, Salvage Value, Percentage			28.00%								28.00%
Dry Van Trailers [Member] | Maximum [Member]
Property, Plant and Equipment, Salvage Value, Percentage			21.00%								21.00%
Revenue Equipment [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)											3 years
Capital Leases of Lessee, Term of Contract (Month)											48 months
Revenue Equipment [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)											10 years
Capital Leases of Lessee, Term of Contract (Month)											84 months
Intangible Assets, Amortization Period [Member]
Depreciation, Depletion and Amortization, Nonproduction, Total											$ 3,200
Net Income (Loss) Attributable to Parent, Total											$ (2,500)
Earnings Per Share, Diluted, Total (in dollars per share) | $ / shares											$ (0.14)
Customer Concentration Risk [Member] | Revenue Benchmark [Member]
Number of Major Customers											10	10	10
Concentration Risk, Percentage											48.00%	45.00%	49.00%
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | One Customer [Member]
Number of Major Customers											1	1	1
Transport Financial Services [Member] | Discontinued Operations, Held-for-sale [Member]
Disposal Group, Including Discontinued Operation, Accounts, Notes and Loans Receivable, Net	$ 103,300		$ 0				86,620				$ 0	$ 86,620
Disposal Group, Including Discontinued Operation, Consideration	122,300			$ 108,400
Proceeds from Divestiture of Businesses	108,400
Disposal Group, Including Discontinued Operation, Consideration, Equity Interest Acquired	13,900
Disposal Group, Including Discontinued Operation, Earnout Opportuntiy, Maximum	9,900
Disposal Group Including Discontinued Operation, Dispute over Nature of Assets	66,000
Disposal Group, Including Discontinued Operation, Consideration Returned upon Settlement			28,100				28,100				28,100	28,100	$ 17,300
Disposal Group Including Discontinued Operation, Assets Advances Against Future Payments For Services Not Yet Performed	62,000
Disposal Group Including Discontinued Operation, Indemnity, Loss Amount	$ 30,000
Disposal Group Including Discontinued Operation, Indemnity, Percentage of Next 30 Million Loss	50.00%
Disposal Group Including Discontinued Operation, Total Indemnification	$ 45,000
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax, Total	$ 3,700
Disposal Group, Including Discontinued Operation, Contingent Liabilities			44,151				$ 0				44,151	$ 0
Transport Financial Services [Member] | Discontinued Operations, Held-for-sale [Member] | Minimum [Member]
Disposal Group Including Discontinued Operation, Total Indemnification			44,200								44,200
Transport Financial Services [Member] | Discontinued Operations, Held-for-sale [Member] | Maximum [Member]
Disposal Group Including Discontinued Operation, Total Indemnification			$ 45,000								$ 45,000
Forecast [Member]
Insurance Policy Primary Occurence Limit															$ 7,000	$ 9,000
Insurance Policy Excess Coverage															$ 3,000	$ 1,000
Transport Enterprise Leasing LLC [Member]
Equity Method Investment, Ownership Percentage			49.00%								49.00%