Note 9 - Subsequent Events (Details Textual) - Subsequent Event [Member] - USD ($) $ / shares in Units, $ in Millions	Jan. 19, 2021	Jan. 26, 2021
Dividends Payable, Date Declared	Jan. 19, 2021
Dividends Payable, Amount Per Share (in dollars per share)	$ 0.28
Dividends Payable, Date of Record	Feb. 01, 2021
Dividends Payable, Date to be Paid	Feb. 12, 2021
Dividends Payable		$ 5.7

Date the declared dividend will be paid, in CCYY-MM-DD format.

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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