Note 8 - Stockholders' Equity - Dividend Activity (Details) - USD ($) $ / shares in Units, $ in Thousands  | 
9 Months Ended | |
|---|---|---|
Sep. 30, 2020  | 
Sep. 30, 2019  | 
|
| Dividends per share (in dollars per share) | $ 0.60 | |
| Dividends | $ 6,855 | $ 2,736 | 
| Dividends Declared February 10, 2020 [Member] | ||
| Dividends per share (in dollars per share) | $ 0.20 | |
| Dividends | $ 2,285 | |
| Dividends Declared May 4, 2020 [Member] | ||
| Dividends per share (in dollars per share) | $ 0.20 | |
| Dividends | $ 2,285 | |
| Dividends Declared August 3, 2020 [Member] | ||
| Dividends per share (in dollars per share) | $ 0.20 | |
| Dividends | $ 2,285 | |
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- Definition Aggregate dividends paid during the period for each share of common stock outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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| X | ||||||||||
- Definition Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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| X | ||||||||||
- Details 
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- Details 
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- Details 
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