Note 11 - Stock Options and Restricted Stock - Summary of Stock Option Activity (Details) - $ / shares	6 Months Ended	12 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Outstanding (in shares)	11,569
Outstanding, weighted average exercise price (in dollars per share)	$ 5.87
Outstanding, weighted average remaining contractual life (Year)	11 months 1 day	6 months 10 days
Forfeited or Expired (in shares)	8,635
Forfeited or Expired, weighted average exercise price (in dollars per share)	$ 5.98
Outstanding (in shares)	2,934	11,569
Outstanding, weighted average exercise price (in dollars per share)	$ 5.55	$ 5.87
Vested (in shares)	2,934
Vested, weighted average exercise price (in dollars per share)	$ 5.55
Vested, weighted average remaining contractual life (Year)	11 months 1 day
Exercisable (in shares)	2,934
Exercisable, weighted average exercise price (in dollars per share)	$ 5.55
Exercisable, weighted average remaining contractual life (Year)	11 months 1 day

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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-Section 50
-Paragraph 2
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-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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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 options outstanding that can 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 price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, 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 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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