Note 7 - Stockholders' Equity and Stock Incentive Plans - Dividends (Details)	6 Months Ended
Jun. 30, 2022 $ / shares
Dividend Declared February 03, 2022 [Member]
Dividends, record date	Mar. 15, 2022
Dividends, payment date	Apr. 15, 2022
Dividends, amount per share (in dollars per share)	$ 0.15
Dividend Declared June 01, 2022 [Member]
Dividends, record date	Jun. 30, 2022
Dividends, payment date	Jul. 15, 2022
Dividends, amount per share (in dollars per share)	$ 0.15

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4304-108586

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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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- Definition

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

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