Note 3 - Stock-based Compensation (Details Textual) - USD ($)	6 Months Ended	13 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)	0
Restricted Stock [Member]
Share-based Payment Arrangement, Expense	$ 54,000	$ 0
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expense	169,000	$ 183,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 111,000		$ 111,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	9 months 25 days
Incentive Plan 2020 [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	0	0	8,912
The2004 Plan Member
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)	0	0
Incentive Plan 2020 [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)	1,800,000		1,800,000

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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The number of grants made 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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