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Fair Value Measurements and Fair Value of Financial Instruments - Additional Information (Detail)
Jun. 30, 2020
USD ($)
Debt Securities, Available-for-sale [Line Items]  
Marketable securities $ 55,700,000
Other than temporary impaired investments $ 0
Minimum  
Debt Securities, Available-for-sale [Line Items]  
Marketable securities term 1 year
Maximum  
Debt Securities, Available-for-sale [Line Items]  
Marketable securities term 2 years