Fair Value Measurements - Assets and Liabilities Carried at Fair Value Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable Securities	$ 81,897	$ 32,965
Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	144,516	205,065
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(188)	0
Fair Value	144,328	205,065
Cash Equivalents	62,431	172,100
Marketable Securities	81,897	32,965
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value		155,551
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	62,431	155,551
Cash Equivalents	62,431	155,551
Marketable Securities	0	0
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets (Level 1) [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	62,431	155,551
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	62,431	155,551
Cash Equivalents	62,431	155,551
Marketable Securities	0	0
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	82,085	49,514
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(188)	0
Fair Value	81,897	49,514
Cash Equivalents	0	16,549
Marketable Securities	81,897	32,965
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	28,781	49,514
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	28,781	49,514
Cash Equivalents	0	16,549
Marketable Securities	28,781	$ 32,965
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member] | U.S. Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying Value	53,304
Gross Unrealized Gains	0
Gross Unrealized Losses	(188)
Fair Value	53,116
Cash Equivalents	0
Marketable Securities	$ 53,116