Marketable Securities - Summary of Available -for-sale Marketable Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Marketable Securities [Line Items]
Amortized Cost	$ 785,473	$ 742,215
Gross Unrealized Gains	522	62
Gross Unrealized Losses	(656)	(3,823)
Estimated Fair Value	785,339	738,454
U S Treasury And Other Government Backed Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	382,260	244,562
Gross Unrealized Gains	302	62
Gross Unrealized Losses	(254)	(1,938)
Estimated Fair Value	382,308	242,686
Financial Institution Debt Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	246,270	380,891
Gross Unrealized Gains	92	0
Gross Unrealized Losses	(243)	(1,030)
Estimated Fair Value	246,119	379,861
Corporate Debt Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	97,490	102,059
Gross Unrealized Gains	53	0
Gross Unrealized Losses	(135)	(509)
Estimated Fair Value	97,408	101,550
Other Asset Backed Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	59,453	14,703
Gross Unrealized Gains	75	0
Gross Unrealized Losses	(24)	(346)
Estimated Fair Value	$ 59,504	$ 14,357

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
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-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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