Note 12 - Subsequent Events (Details Textual) - $ / shares |
3 Months Ended | ||
|---|---|---|---|
Jul. 22, 2020 |
Jun. 30, 2020 |
Jun. 30, 2019 |
|
| Common Stock, Dividends, Per Share, Declared (in dollars per share) | $ 1 | $ 1 | |
| Subsequent Event [Member] | |||
| Common Stock, Dividends, Per Share, Declared (in dollars per share) | $ 1 | ||
| Subsequent Event [Member] | Common Stock [Member] | |||
| Dividends Payable, Date to be Paid | Aug. 31, 2019 | ||
| Dividends Payable, Date of Record | Aug. 03, 2019 | ||