Note 15 - Subsequent Events (Details Textual) - Managing Director, China Operations [Member] - Subsequent Event [Member] - Stock Option Plan 2016 [Member]	Nov. 09, 2021 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in shares) \| shares	171,429
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price (in dollars per share) \| $ / shares	$ 1.93

Number of share options (or share units) exercised during the current period.

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