Note 14 - Stockholders' Equity - Summary of Outstanding Options (Details) - USD ($)	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Quantity, outstanding (in shares)	45,468	76,064
Quantity, vested (in shares)	45,468
Weighted-average exercise price, outstanding (in dollars per share)	$ 14.28	$ 27.35
Weighted-average exercise price, vested (in dollars per share)	$ 14.28
Weighted average remaining contractual term, outstanding (Year)	2 years 9 months 3 days
Weighted average remaining contractual term , vested (Year)	2 years 9 months 3 days
Intrinsic value, outstanding	$ 0

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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