Marketable Securities - Summary of Available -for-sale Marketable Securities (Detail) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Marketable Securities [Line Items]
Amortized Cost	$ 826,633	$ 742,215
Gross Unrealized Gains	47	62
Gross Unrealized Losses	(2,167)	(3,823)
Estimated Fair Value	824,513	738,454
U.S. Treasury and Other Government - Backed Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	330,875	244,562
Gross Unrealized Gains	3	62
Gross Unrealized Losses	(935)	(1,938)
Estimated Fair Value	329,943	242,686
Financial Institution Debt Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	319,226	380,891
Gross Unrealized Gains	40	0
Gross Unrealized Losses	(688)	(1,030)
Estimated Fair Value	318,578	379,861
Corporate Debt Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	115,344	102,059
Gross Unrealized Gains	4	0
Gross Unrealized Losses	(306)	(509)
Estimated Fair Value	115,042	101,550
Other Asset Backed Securities [Member]
Marketable Securities [Line Items]
Amortized Cost	61,188	14,703
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(238)	(346)
Estimated Fair Value	$ 60,950	$ 14,357