Financial Statement Details - Interest and Investment (Loss) Income, Net (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Investment Income, Net [Abstract]
Unrealized (losses) gains from equity securities	$ (4,615)	$ 1,577	$ (321)
Interest income	836	1,725	2,764
Investment (amortization expense) accretion income, net	(488)	(858)	3
Net realized gains (losses) on investments	167	(9)	(4)
Interest and investment (loss) income, net	$ (4,100)	$ 2,435	$ 2,442

Amount of unrealized gain (loss) on investment in debt and equity securities.

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Amount of realized and unrealized gain (loss) on investment.

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The amount of interest income and other income recognized during the period. Included in this element is interest derived from investments in debt securities, cash and cash equivalents, and other investments which reflect the time value of money or transactions in which the payments are for the use or forbearance of money and other income from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business).

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Amount of accretion (amortization) of purchase discount (premium) on nonoperating securities.

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Amount of realized gain (loss) on investment.

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