Note 7 - Equity - Summary of Option Awards (Detail) - $ / shares	3 Months Ended	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares Underlying Options	70,000
MedAmerica [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares Underlying Options	70,000	70,000	70,000	70,000
Weighted Average Exercise Price Per Share	$ 7.71	$ 7.71	$ 7.71	$ 7.71
Weighted Average Remaining Contractual Life	1 year 6 months 3 days	2 years 6 months 3 days	1 year 9 months 3 days	2 years 9 months 3 days

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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

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-Publisher FASB
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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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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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