Note 9 - Leases (Details Textual) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2021 |
Dec. 31, 2020 |
|
| Operating Lease, Weighted Average Remaining Lease Term (Year) | 7 months 6 days | |
| Operating Lease, Weighted Average Discount Rate, Percent | 7.00% | |
| Variable Lease, Payment | $ 29 | |
| Short-term Lease, Cost | 0 | $ 0 |
| Improved Office and Warehouse in Tempe, Arizona [Member] | ||
| Operating Lease, Right-of-Use Asset, Amortization Expense | 88 | 122 |
| Operating Lease, Expense | $ 95 | $ 137 |