4. Stock Incentive Plan (Details) - $ / shares |
3 Months Ended | 12 Months Ended | ||||||
---|---|---|---|---|---|---|---|---|
Mar. 31, 2021 |
Mar. 31, 2020 |
Dec. 31, 2020 |
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Share-based Payment Arrangement [Abstract] | ||||||||
Stock options outstanding, beginning | 1,258,577 | 1,087,463 | 1,087,463 | |||||
Stock options, granted | 196,476 | [1] | 163,357 | 174,357 | ||||
Stock options, forfeited | (3,344) | [2] | (3,243) | |||||
Stock options, exercised | (2,913) | |||||||
Stock options outstanding, ending | 1,448,796 | 1,258,577 | ||||||
Weighted average exercise price outstanding, beginning | $ 4.47 | $ 2.94 | $ 2.94 | |||||
Weighted average exercise price, granted | 6.93 | [1] | 14.08 | |||||
Weighted average exercise price, forfeited | 17.25 | [2] | 8.47 | |||||
Weighted average exercise price, exercised | 6.00 | |||||||
Weighted average exercise price outstanding, ending | $ 4.77 | $ 4.47 | ||||||
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