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

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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