Note 9 - Commitments and Contingencies (Details Textual)				3 Months Ended		6 Months Ended
	Jun. 01, 2022 USD ($)	May 24, 2022	May 09, 2022	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	May 12, 2022 ft²	Dec. 31, 2021 USD ($)
Loss Contingencies [Line Items]
Operating Lease, Right-of-Use Asset				$ 363,000		$ 363,000			$ 109,000
Operating Lease, Liability, Current				98,000		98,000			112,000
Operating Lease, Liability, Noncurrent				266,000		266,000			0
Imputed interest				66,000		66,000
Insurance Financing Arrangement [Member]
Loss Contingencies [Line Items]
Line of Credit Facility, Interest Rate During Period		6.92%	3.82%
Line of Credit Facility, Expiration Period		10 months	9 months
Remaining balance under insurance financing arrangements				$ 600,000		$ 600,000			$ 100,000
Base Rate [Member]
Loss Contingencies [Line Items]
Base Rent Rate Percentage	50.00%
Corporate Office [Member]
Loss Contingencies [Line Items]
Area of real estate property (Square Foot) | ft²								2,747
Lessee, operating lease, term of contract (Month)								39 months
Lessee, operating lease, renewal term (Month)								36 months
Lease monthly payment	$ 10,850
Operating lease, contractual monthly lease payments, yearly escalation rate	3.00%
Payments for (Proceeds from) Tenant Allowance	$ 28,000
Operating Lease, Right-of-Use Asset	355,000
Operating Lease, Liability, Current	83,000
Operating Lease, Liability, Noncurrent	$ 272,000
Lessee, Operating Lease, Discount Rate	10.75%
Lessee, Operating Lease, Remaining Lease Term				3 years 2 months 12 days		3 years 2 months 12 days
Operating Lease, Expense				$ 59,000	$ 49,000	$ 108,000	$ 98,000
Imputed interest				66,000		66,000
Total remaining future minimum lease payments				$ 430,000		$ 430,000