Cash, Cash Equivalents, Restricted Cash and Marketable Securities - Maturities of Marketable Securities Available-for-Sale (Detail) $ in Thousands	Jun. 30, 2021 USD ($)
Amortized Cost
Mature in one year or less	$ 214,386
Mature after one year through two years	1,750
Total amortized cost	216,136
Estimated Fair Value
Mature in one year or less	214,446
Mature after one year through two years	1,750
Total estimated fair value	$ 216,196

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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