Note 7 - Debt (Details Textual) - USD ($)					3 Months Ended		6 Months Ended
	Jul. 08, 2021	Feb. 11, 2021	Sep. 23, 2020	Apr. 10, 2020	Sep. 30, 2020	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	Aug. 10, 2017
Repayments of Long-term Debt, Total							$ 72,000	$ 49,000
Long-term Debt, Total							$ 17,059,000		$ 22,480,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)							$ 3.57		$ 3.73
Interest Expense [Member]
Amortization of Debt Issuance Costs						$ 24,000		58,000
Other Assets [Member]
Unamortized Debt Issuance Expense							$ 0		$ 0
Warrant Issued in Connection with Amended 2017 Credit Agreement [Member]
Warrants and Rights Outstanding, Term (Year)			5 years
Class of Warrant or Right, Number of Securities Called by Each Warrant or Right (in shares)			1,000,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)			$ 3.75
Warrants and Rights Outstanding			$ 1,400,000
Conversion from 2017 Credit Agreement Loan Concession to Common Stock [Member]
Debt Conversion, Converted Instrument, Shares Issued (in shares)			533,334
Shares Issued, Price Per Share (in dollars per share)			$ 2.0775
Debt Conversion, Converted Instrument, Amount			$ 1,100,000
Revolving Credit Facility [Member]
Debt Instrument, Interest Rate, Stated Percentage							8.25%		8.25%
Debt Instrument, Interest Rate, Calculated Monthly and Paid in Arrears							5.25%		5.25%
Debt Instrument, Interest Rate, Accrued on Principal Balance							3.00%		3.00%
Long-term Debt, Total							$ 14,980,000		$ 19,078,000
The 2017 Credit Agreement [Member] | East West Bank [Member]
Debt Instrument, Interest Rate, Stated Percentage			8.25%
Debt Instrument, Interest Rate, Calculated Monthly and Paid in Arrears			5.25%
Debt Instrument, Interest Rate, Accrued on Principal Balance			3.00%
Debt Instrument, Covenant, Minimum Liquidity									$ 1,500,000
Debt Instrument, Covenant, Percentage of Projected Gross Revenue Achieved							70.00%
Debt Instrument, Covenant, Maximum Capital Expenditures							$ 1,200,000
Gains (Losses) on Restructuring of Debt					$ 11,900,000
The 2017 Credit Agreement [Member] | East West Bank [Member] | Equipment Term Loan [Member]
Debt Instrument, Face Amount			$ 17,000,000.0
Repayments of Long-term Debt, Total		$ 3,000,000.0
Long-term Debt, Total							$ 14,000,000.0
Debt, Weighted Average Interest Rate							8.25%
Long-term Debt, Gross							$ 15,000,000.0
Interest Payable							1,000,000.0
The 2017 Credit Agreement [Member] | East West Bank [Member] | Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity, Percent of Eligible Receivables										85.00%
Line of Credit Facility, Maximum Borrowing Capacity, Percentage of Trucks and Equipment										85.00%
Line of Credit Facility, Decrease, Forgiveness			16,000,000.0
Line of Credit Facility, Maximum Borrowing Capacity			$ 1,000,000.0
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage			0.50%
Line of Credit Facility, Remaining Borrowing Capacity							$ 1,000,000.0
Paycheck Protection Program CARES Act [Member]
Debt Instrument, Interest Rate, Stated Percentage							1.00%		1.00%
Long-term Debt, Total							$ 1,940,000		$ 1,940,000
Proceeds from Issuance of Long-term Debt, Total							$ 0	$ 1,940,000
Paycheck Protection Program CARES Act [Member] | East West Bank [Member]
Proceeds from Issuance of Long-term Debt, Total				$ 1,939,900
Debt Instrument, Decrease, Forgiveness	$ 1,900,000
Debt Instrument, Decrease, Forgiveness of Accrued Interest	$ 24,000