Cash, Cash Equivalents and Investments - Amortized Cost to Fair Value (Detail) $ in Thousands	Dec. 31, 2022 USD ($)
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 699,693
Gross Unrealized Gains	743
Gross Unrealized Losses	(27,560)
Fair Value, Total	672,876
Treasury Bills [Member]
Debt Securities, Available-for-sale [Line Items]
Fair Value, Total	55,546
Treasury Bills [Member] \| Long-term investments [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	44,333
Gross Unrealized Gains	79
Gross Unrealized Losses	(198)
Fair Value, Total	44,214
Treasury Bills [Member] \| Short-term Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	11,602
Gross Unrealized Gains	0
Gross Unrealized Losses	(270)
Fair Value, Total	11,332
Asset-Backed Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fair Value, Total	60,429
Asset-Backed Securities [Member] \| Long-term investments [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	35,144
Gross Unrealized Gains	103
Gross Unrealized Losses	(1,708)
Fair Value, Total	33,539
Asset-Backed Securities [Member] \| Short-term Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	27,607
Gross Unrealized Gains	0
Gross Unrealized Losses	(717)
Fair Value, Total	26,890
Corporate Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Fair Value, Total	538,495
Corporate Bonds [Member] \| Long-term investments [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	394,576
Gross Unrealized Gains	561
Gross Unrealized Losses	(20,697)
Fair Value, Total	374,440
Corporate Bonds [Member] \| Short-term Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	167,558
Gross Unrealized Gains	0
Gross Unrealized Losses	(3,503)
Fair Value, Total	164,055
Sovereign Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Fair Value, Total	1,924
Sovereign Bonds [Member] \| Long-term investments [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,095
Gross Unrealized Gains	0
Gross Unrealized Losses	(171)
Fair Value, Total	1,924
Municipal Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Fair Value, Total	624
Municipal Bonds [Member] \| Short-term Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	635
Gross Unrealized Gains	0
Gross Unrealized Losses	(11)
Fair Value, Total	624
Agency Bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Fair Value, Total	15,858
Agency Bonds [Member] \| Short-term Investments [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	16,143
Gross Unrealized Gains	0
Gross Unrealized Losses	(285)
Fair Value, Total	$ 15,858

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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