Investments - Debt Securities Available-For-Sale (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Unrealized Losses, Less than 12 Months	$ (21)	$ (9)
Fair Value, Less than 12 Months	42,056	26,650
Unrealized Losses	(21)	(9)
Fair Value	42,056	26,650
Corporate Debt Securities [Member]
Unrealized Losses, Less than 12 Months	(7)	(6)
Fair Value, Less than 12 Months	8,123	16,655
Unrealized Losses	(7)	(6)
Fair Value	8,123	16,655
Commercial Paper [Member]
Unrealized Losses, Less than 12 Months	(6)	(3)
Fair Value, Less than 12 Months	11,984	9,995
Unrealized Losses	(6)	(3)
Fair Value	11,984	$ 9,995
U.S. government and agency securities [Member]
Unrealized Losses, Less than 12 Months	(8)
Fair Value, Less than 12 Months	21,949
Unrealized Losses	(8)
Fair Value	$ 21,949