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Stock-Based Compensation - Summary of Grant Date Fair Value of Restricted Stock Unit Awards Vested (Detail) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Restricted Stock Units [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Grant-date fair value $ 251 $ 510