Note 9 - Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) |
12 Months Ended | |
|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Gross UTB balance at beginning of fiscal year | $ 162,000 | $ 230,000 |
| Reductions for tax positions of prior years | (12,000) | (68,000) |
| Gross UTB balance at end of fiscal year | $ 150,000 | $ 162,000 |