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Acquisitions - Summary of Unaudited Proforma Results of Operation (Detail) - Avast PLC Family Safety Mobile Software Business [Member] - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Business Acquisition [Line Items] |  |  |  |
Revenues | $ 17,146 | $ 22,085 | $ 36,532 | $ 44,559
Net income (loss) | $ (5,396) | $ 409 | $ (10,092) | $ 1,485
Earnings (loss) per share: |  |  |  |
Basic | $ (0.10) | $ 0.01 | $ (0.21) | $ 0.04
Diluted | $ (0.10) | $ 0.01 | $ (0.21) | $ 0.04

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