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Cash and Investments in Marketable Securities - Additional Information (Detail) - USD ($)
$ in Millions
6 Months Ended 12 Months Ended
Jun. 30, 2021
Dec. 31, 2020
Cash and Investments in Marketable Securities [Line Items]    
Maximum maturity term for debt securities investment 2 years  
Weighted average maturity term for debt securities investment (or less) 1 year  
Debt securities, available-for-sale, accumulated gross unrealized gain, before tax   $ 1.1
Debt securities, available-for-sale accumulated gross unrealized loss, before tax   $ 0.2
Minimum    
Cash and Investments in Marketable Securities [Line Items]    
Long term investment maturity period 1 year 1 year
Maximum    
Cash and Investments in Marketable Securities [Line Items]    
Long term investment maturity period 2 years 2 years