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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands | 9 Months Ended
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Sep. 30, 2021 | Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Aggregate intrinsic value, options exercised | $ 13 | $ 43
Options granted, weighted average grant date fair value (in usd per share) | $ 5.39 | $ 6.93
Restricted Stock Units (RSUs) |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Unrecognized compensation cost of stock based awards | $ 8,600 |
Unrecognized compensation cost of stock based awards, recognition period | 2 years 3 months 18 days |
2019 Equity Incentive Plan |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Shares reserved for issuance | 725,000 |

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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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