Marketable Securities - Summary of Company Marketable Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost / Cost	$ 505,846	$ 183,623
Unrealized Gains	64	555
Unrealized Losses	(1,773)	(55)
Fair Value	504,137	184,123
U.S. Government and Agency Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost / Cost	60,118	12,782
Unrealized Gains		22
Unrealized Losses	(229)
Fair Value	59,889	12,804
Certificates of Deposit [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost / Cost	2,936	1,956
Unrealized Gains	2	34
Unrealized Losses	(11)
Fair Value	2,927	1,990
Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost / Cost	442,792	165,850
Unrealized Gains	62	497
Unrealized Losses	(1,533)	(55)
Fair Value	$ 441,321	166,292
Municipal Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost / Cost		3,035
Unrealized Gains		2
Fair Value		$ 3,037

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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