Note 4 - Net Income Per Share (Details Textual) - shares |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2015 |
Sep. 30, 2014 |
Sep. 30, 2015 |
Sep. 30, 2014 |
|
| Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | 4,000 | 4,000 | 4,000 | 4,000 |