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Related Party Transactions - Additional Information (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Consulting Services [Member] | Related Party One [Member]      
Related Party Transaction [Line Items]      
Rent and other expenses paid $ 0.1 $ 0.2 $ 0.2