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Stock Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Jun. 13, 2018 | Dec. 31, 2019 | Dec. 31, 2018
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] |  |  |
Stock options granted |  | 450,900 | 612,050
Number of common stock available for future grant |  | 1,014,126 |
Number of shares of common stock issued to certain board members in lieu of cash compensation |  | 24,235 | 6,790
Shares remaining outstanding |  | 1,577,541 |
Stock-based compensation expense |  | $ 3,204 | $ 2,606
Employee Stock Option |  |  |
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] |  |  |
Expected term of stock options |  | 5 years 11 months 23 days | 6 years 14 days
Unrecognized employee stock based compensation expense |  | $ 5,300 |
Unrecognized employee stock based compensation expense, period for recognition |  | 2 years 4 months 28 days |
2018 Employee Stock Purchase Plan |  |  |
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] |  |  |
Number of common stock available for future grant |  | 218,692 |
Number of common stock authorized for issuance |  | 239,545 |
Number of common stock stock issued |  | 20,853 |
Stock-based compensation expense |  | $ 100 | $ 30
2018 Omnibus Incentive Plan |  |  |
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] |  |  |
Number of common stock available for future grant | 1,500,000 |  |
2018 Employee Stock Purchase Plan |  |  |
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] |  |  |
Maximum employee subscription rate | 15.00% |  |
2018 Employee Stock Purchase Plan | Maximum |  |  |
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] |  |  |
Percentage of fair market value of common stock | 85.00% |  |

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- Definition 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. + 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 (i) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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