Note 12 - Common Stock Options (Details Textual) - shares |
12 Months Ended | 156 Months Ended | |||||
|---|---|---|---|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2004 |
Dec. 31, 2000 |
Dec. 31, 1997 |
Dec. 31, 2016 |
|
| Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 450,000 | ||||||
| Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term | 91 days | 91 days | 91 days | ||||
| Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period | 1 year | ||||||
| Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | 0 | 0 | 0 | 40,049 | 54,000 | 450,000 | 0 |
| Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period | 0 | 0 | 0 | ||||
| Maximum [Member] | |||||||
| Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term | 10 years | ||||||