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Cash Flow Statement - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2020 | Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Interest paid |  |  | $ 9 | $ 9
Income taxes paid |  |  | 51 | 27
Issuance of treasury stock | $ 87 | $ 49 |  |
Capital expenditures |  |  | 37 | 10
Employee Stock Purchase Plan [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Issuance of treasury stock |  |  | $ 87 | $ 49

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