Note 13 - Stock Based Compensation - Summary of Stock Option Activity (Details) - $ / shares	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Outstanding, shares (in shares)	42,283
Outstanding, weighted-average exercise price (in dollars per share)	$ 6.20
Outstanding, weighted-average remaining contractual term (Year)		9 months 18 days
Cancelled/Forfeited, shares (in shares)	(36,071)
Cancelled/Forfeited, weighted-average exercise price (in dollars per share)	$ 5.54
Expired, shares (in shares)	(6,212)
Expired, weighted-average exercise price (in dollars per share)	$ 10.01

Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(4)
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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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

+ References

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