Cash and Cash Equivalents (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Cash
Fair Value Measurements [Line Items]
Amortized Cost	$ 96,649	$ 196,106
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	96,649	196,106
Money market securities
Fair Value Measurements [Line Items]
Amortized Cost	51,794	101,581
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	51,794	101,581
Total cash equivalents
Fair Value Measurements [Line Items]
Amortized Cost	51,794	101,581
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	51,794	101,581
Total cash and cash equivalents
Fair Value Measurements [Line Items]
Amortized Cost	148,443	297,687
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	$ 148,443	$ 297,687

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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