Available-for-Sale Marketable Securities in Unrealized Position (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	$ 48,631
Less than 12 Months, Unrealized Loss	(250)
12 Months or Greater, Fair Value	2,017
12 Months or Greater, Unrealized Loss	(5)
Total, Fair Value	50,648
Total, Unrealized Loss	(255)
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	27,909	$ 5,105
Less than 12 Months, Unrealized Loss	(153)	(3)
12 Months or Greater, Fair Value	998
12 Months or Greater, Unrealized Loss	(3)
Total, Fair Value	28,907	5,105
Total, Unrealized Loss	(156)	$ (3)
United States government agency securities
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	18,367
Less than 12 Months, Unrealized Loss	(75)
12 Months or Greater, Fair Value	1,019
12 Months or Greater, Unrealized Loss	(2)
Total, Fair Value	19,386
Total, Unrealized Loss	(77)
Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Less than 12 Months, Fair Value	2,355
Less than 12 Months, Unrealized Loss	(22)
12 Months or Greater, Fair Value	0
12 Months or Greater, Unrealized Loss	0
Total, Fair Value	2,355
Total, Unrealized Loss	$ (22)