Marketable Securities - Summary of Available -for-sale Marketable Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Marketable Securities [Line Items]
Amortized Cost	$ 782,351	$ 785,473
Gross Unrealized Gains	111	522
Gross Unrealized Losses	(1,057)	(656)
Estimated Fair Value	781,405	785,339
U.S. Treasury and Other Government - Backed Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	401,660	382,260
Gross Unrealized Gains	40	302
Gross Unrealized Losses	(589)	(254)
Estimated Fair Value	401,111	382,308
Financial Institution Debt Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	214,001	246,270
Gross Unrealized Gains	56	92
Gross Unrealized Losses	(292)	(243)
Estimated Fair Value	213,765	246,119
Corporate Debt Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	112,194	97,490
Gross Unrealized Gains	12	53
Gross Unrealized Losses	(129)	(135)
Estimated Fair Value	112,077	97,408
Other Asset Backed Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	54,496	59,453
Gross Unrealized Gains	3	75
Gross Unrealized Losses	(47)	(24)
Estimated Fair Value	$ 54,452	$ 59,504

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).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
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Amount, before tax, of unrealized loss 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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
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-Name Accounting Standards Codification
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