11. Stock-based Compensation (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Share-based compensation expense	$ 136	$ 300
2020 Long-Term Incentive Plan [Member]
Shares reserved for issuance	1,267,675
Shares available for future grants	1,254,906
Restricted Stock [Member] \| Dr. Cauwenbergh [Member]
Share-based compensation expense		$ 106
Issuance of restricted stock, shares		4,419
Restricted Stock Units R S U [Member]
Share-based compensation expense	$ 85	$ 125
Unrecognized compensation expense - other than options	$ 151
Unrecognized compensation expense weighted average period	2 years 4 months 6 days
Other than options, nonvested	9,699	14,945
Options [Member]
Weighted average grant date fair value per share of options granted		$ 16.50
Share-based compensation expense	$ 51	$ 69
Unrecognized compensation expense - options	$ 58
Unrecognized compensation expense weighted average period	1 year 5 months 20 days
Options outstanding	2,570	2,659
Options [Member] \| 2020 Long-Term Incentive Plan [Member]
Options outstanding	2,570

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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