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v3.20.4

Share-Based Compensation - Intrinsic Value (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Share-based compensation |  |
Intrinsic value of options vested | $ 393,952 | $ 436,000
Intrinsic value of options exercised | $ 843,893 | $ 11,100

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- Definition Share Based Compensation Arrangement by Share Based Payment Award, Options, Vested in Period, Total Intrinsic Value + References No definition available. + Details
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- References No definition available. + Details
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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