Note 8 - Shareholders' Equity - Summary of Nonvested Option Activity (Details) - $ / shares shares in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Nonvested at January 1, 2021 (in shares)	373
Nonvested at January 1, 2021 (in dollars per share)	$ 9.39
Granted (in shares)	193	184	250
Granted (in dollars per share)	$ 7.50
Vested (in shares)	(185)
Vested (in dollars per share)	$ 9.61
Forfeited (in shares)	(34)
Forfeited (in dollars per share)	$ 8.42
Nonvested at December 31, 2021 (in shares)	347	373
Nonvested at December 31, 2021 (in dollars per share)	$ 8.31

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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-Publisher FASB
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-SubTopic 10
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Gross number of share options (or share units) granted during the period.

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