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Cash Flow Statement - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Interest paid |  |  | $ 7 | $ 3
Income taxes paid |  |  | 14 | 976
Issuance of treasury stock | $ 49 | $ 79 |  |
Capital expenditures |  |  | 87 | 68
Employee Stock Purchase Plan [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Issuance of treasury stock |  |  | $ 49 | $ 79

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