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Fair Value Measurements - Schedule of Available-for-sale Investments (Detail) - USD ($)
$ in Thousands
Jun. 30, 2021
Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]    
Gross Amortized Cost $ 41,880 $ 14,730
Gross Unrealized Gains 1 7
Gross Unrealized Losses (12)  
Market Value 41,869 14,737
Short-term Investments [Member] | Commercial Paper [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Gross Amortized Cost 22,583 5,491
Gross Unrealized Gains 1 3
Gross Unrealized Losses (2)  
Market Value 22,582 5,494
Short-term Investments [Member] | Municipal Bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Gross Amortized Cost 1,000  
Gross Unrealized Losses (3)  
Market Value 997  
Short-term Investments [Member] | Asset-backed Securities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Gross Amortized Cost 1,001 2,218
Gross Unrealized Gains   1
Market Value 1,001 2,219
Short-term Investments [Member] | Corporate Debt Securities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Gross Amortized Cost 17,296 7,021
Gross Unrealized Gains   3
Gross Unrealized Losses (7)  
Market Value $ 17,289 $ 7,024