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	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Business Acquisition [Line Items]
Revenues	$ 16,443	$ 21,781	$ 52,975	$ 66,340
Net (loss) income	$ (5,493)	$ (684)	$ (13,648)	$ 551
(Loss) earnings per share:
Basic	$ (0.10)	$ (0.01)	$ (0.26)	$ 0.01
Diluted	$ (0.10)	$ (0.01)	$ (0.26)	$ 0.01

Pro forma basic earnings per share or earnings per unit, which is commonly presented in initial public offerings based on the terms of the offering.

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