Note 5 - Fair Value of Marketable Securities (Details) - USD ($) |
Jun. 30, 2015 |
|---|---|
| Fair Market Value | $ 87,991,589 |
| Marketable securities, debt maturities due within one year, fair value | 17,559,217 |
| Marketable securities, debt maturities due after one year through three years, fair value | 47,260,141 |
| Marketable securities, debt maturities due after three years through five years, fair value | $ 23,172,231 |