Note 3 - Short Term Investments Available for Sale - Investment Securities Gross Unrealized Losses and Fair Value by Investment Category (Details) |
Dec. 31, 2015
USD ($)
|
|---|---|
| Available for sale (all unrealized holding gains and losses are less than 12 months at date of measurement) | |
| Total | $ 10,799,890 |
| Total | (3,858) |
| Certificates of Deposit [Member] | |
| Available for sale (all unrealized holding gains and losses are less than 12 months at date of measurement) | |
| Short-term investments with unrealized gains | 240,024 |
| Short-term investments with unrealized gains | 24 |
| Short-term investments with unrealized losses | 4,558,786 |
| Short-term investments with unrealized losses | (1,214) |
| Corporate Bond Securities [Member] | |
| Available for sale (all unrealized holding gains and losses are less than 12 months at date of measurement) | |
| Short-term investments with unrealized losses | 6,001,080 |
| Short-term investments with unrealized losses | $ (2,668) |