Note 11 - Income Taxes - Change in Gross Balance of Unrecognized Tax Benefit (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2017 |
Mar. 31, 2016 |
Mar. 31, 2015 |
|
| Beginning balance | $ 221,000 | ||
| Increases related to current period tax positions | 110,000 | 221,000 | |
| Ending balance | $ 331,000 | $ 221,000 | |