Marketable Securities - Summary of Available -for-sale Marketable Securities (Detail) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Marketable Securities [Line Items]
Amortized Cost	$ 865,203	$ 742,215
Gross Unrealized Gains	789	62
Gross Unrealized Losses	(1,562)	(3,823)
Estimated Fair Value	864,430	738,454
U.S. Treasury and Other Government Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	261,410	244,562
Gross Unrealized Gains	587	62
Gross Unrealized Losses	(460)	(1,938)
Estimated Fair Value	261,537	242,686
Financial Institution Debt Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	460,173	380,891
Gross Unrealized Gains	69	0
Gross Unrealized Losses	(740)	(1,030)
Estimated Fair Value	459,502	379,861
Corporate Debt Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	107,111	102,059
Gross Unrealized Gains	52	0
Gross Unrealized Losses	(140)	(509)
Estimated Fair Value	107,023	101,550
Other Asset Backed Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	36,509	14,703
Gross Unrealized Gains	81	0
Gross Unrealized Losses	(222)	(346)
Estimated Fair Value	$ 36,368	$ 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).

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