Cash, Cash Equivalents, Restricted Cash and Marketable Securities - Maturities of Marketable Securities Available-for-Sale (Detail) $ in Thousands	Sep. 30, 2021 USD ($)
Amortized Cost
Mature in one year or less	$ 167,762
Mature after one year through two years	0
Total amortized cost	167,762
Estimated Fair Value
Mature in one year or less	167,804
Mature after one year through two years	0
Total estimated fair value	$ 167,804

Amortized cost of 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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