Subsequent Events - Additional Information (Detail) - Avast PLC Family Safety Mobile Business [Member] - Subsequent Event [Member] $ in Millions	Apr. 16, 2021 USD ($) shares
Subsequent Event [Line Items]
Aggregate purchase price	$ 66.0
Escrow amount	5.0
Cash payments to acquire business, excluding working capital adjustments and other closing adjustments	$ 51.1
Common Stock [Member]
Subsequent Event [Line Items]
Issuance of common stock in connection with acquisition \| shares	1,460,131
Issuance of common stock value in connection with acquisition	$ 8.4

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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