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Severance and Retention - Additional Information (Detail)
$ in Thousands
12 Months Ended
Dec. 31, 2020
USD ($)
Employee
Dec. 31, 2019
USD ($)
Employee
Restructuring and Related Activities [Abstract]    
Severance and retention expense | $ $ 2,503 $ 1,403
Number of employees associated with reduction in workforce | Employee 39 33