Fair Value Measurement - Summary of Contractual Maturities of Available for Sale Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	$ 66,218	$ 94,570
Available for sale securities, contractual maturities between 1 to 5 years	89,866	133,235
Available for sale securities, contractual maturities between 5 to 10 years	53,230	53,600
Available for sale securities, contractual maturities after 10 years	46,670	13,988
Available for sale securities, contractual maturities, Total	255,984	295,393
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	16,277	7,238
Available for sale securities, contractual maturities between 1 to 5 years	81,828	120,887
Available for sale securities, contractual maturities between 5 to 10 years	25,001	25,936
Available for sale securities, contractual maturities after 10 years	14,129
Available for sale securities, contractual maturities, Total	137,235	154,061
Money Market Funds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	36,530	64,572
Available for sale securities, contractual maturities, Total	36,530	64,572
U.S. Government Agency Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year		2,128
Available for sale securities, contractual maturities between 1 to 5 years	6,505	6,425
Available for sale securities, contractual maturities between 5 to 10 years	28,229	27,664
Available for sale securities, contractual maturities, Total	34,734	36,217
Asset Backed Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities between 1 to 5 years	303	319
Available for sale securities, contractual maturities after 10 years	32,541	13,988
Available for sale securities, contractual maturities, Total	32,844	14,307
U.S. Treasuries [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	8,569	20,632
Available for sale securities, contractual maturities between 1 to 5 years	1,230	804
Available for sale securities, contractual maturities, Total	9,799	21,436
Supranational Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities, contractual maturities less than 1 year	4,842
Available for sale securities, contractual maturities between 1 to 5 years		4,800
Available for sale securities, contractual maturities, Total	$ 4,842	$ 4,800

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 latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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