Fair Value Measurement - Summary of Contractual Maturities of Available for Sale Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	$ 28,063	$ 138,534
Available for sale securities, contractual maturities between 1 to 5 years	86,109	81,754
Available for sale securities, contractual maturities between 5 to 10 years	239,667	56,462
Available for sale securities, contractual maturities after 10 years	34,731	36,793
Available for sale securities, contractual maturities, Total	388,570	313,543
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	24,506	49,308
Available for sale securities, contractual maturities between 1 to 5 years	67,063	61,315
Available for sale securities, contractual maturities between 5 to 10 years	142,029	34,172
Available for sale securities, contractual maturities, Total	233,598	144,795
Money Market Funds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	1,545	82,066
Available for sale securities, contractual maturities, Total	1,545	82,066
U.S. Government Agency Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	1,002	1,013
Available for sale securities, contractual maturities between 1 to 5 years	18,413	18,668
Available for sale securities, contractual maturities between 5 to 10 years	25,384	20,670
Available for sale securities, contractual maturities, Total	44,799	40,351
Asset Backed Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year		2
Available for sale securities, contractual maturities between 1 to 5 years	209	267
Available for sale securities, contractual maturities between 5 to 10 years	2,201
Available for sale securities, contractual maturities after 10 years	34,731	36,793
Available for sale securities, contractual maturities, Total	37,141	37,062
U.S. Treasuries [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	1,010	1,367
Available for sale securities, contractual maturities between 1 to 5 years	424	1,504
Available for sale securities, contractual maturities between 5 to 10 years	70,053	1,620
Available for sale securities, contractual maturities, Total	$ 71,487	4,491
Supranational Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year		4,778
Available for sale securities, contractual maturities, Total		$ 4,778

Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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