Note 9 - Subsequent Event - Dividend (Details Textual) - Subsequent Event [Member] - USD ($) |
Apr. 25, 2018 |
Apr. 11, 2018 |
|---|---|---|
| Common Stock, Dividends, Per Share, Declared | $ 1.25 | |
| Expense Related to Payment of Dividends on Unvested Restricted Stock | $ 94,000 |