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Quarterly Financial Data (Unaudited) - Summary of Company's Unaudited Quarterly Results (Detail) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2020 | Mar. 31, 2019 | Mar. 31, 2018
Quarterly Financial Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net sales | $ 23,082 | $ 25,286 | $ 21,643 | $ 20,593 | $ 23,641 | $ 17,198 | $ 21,441 | $ 29,551 | $ 90,604 | $ 91,831 | $ 77,534
Gross profit | 4,442 | 4,044 | 4,948 | 4,714 | 4,798 | 3,742 | 6,227 | 7,142 | 18,148 | 21,909 | 16,975
Net income (loss) | $ 576 | $ 9 | $ 1,205 | $ 82 | $ (4,553) | $ 95 | $ 1,827 | $ 2,323 | $ 1,872 | $ (308) | $ (9,844)
Per share: |  |  |  |  |  |  |  |  |  |  |
Basic | $ 0.06 |  | $ 0.12 | $ 0.01 | $ (0.46) | $ 0.01 | $ 0.19 | $ 0.24 | $ 0.19 | $ (0.03) | $ (1.01)
Diluted | 0.06 |  | 0.12 | 0.01 | (0.46) | 0.01 | 0.19 | 0.24 | 0.19 | (0.03) | $ (1.01)
Minimum [Member] |  |  |  |  |  |  |  |  |  |  |
Per share: |  |  |  |  |  |  |  |  |  |  |
Market price range of common stock | 11.07 | $ 19.03 | 17.70 | 18.96 | 19.00 | 19.48 | 22.55 | 20.75 | 11.07 | 19.00 |
Maximum [Member] |  |  |  |  |  |  |  |  |  |  |
Per share: |  |  |  |  |  |  |  |  |  |  |
Market price range of common stock | $ 21.90 | $ 23.77 | $ 23.25 | $ 22.84 | $ 24.90 | $ 28.73 | $ 28.98 | $ 27.51 | $ 23.77 | $ 28.98 |

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