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Stockholders' Equity - Additional Information - Deferred Stock Units (Detail) - Deferred Stock Units [Member] - USD ($)
12 Months Ended
Dec. 31, 2019
Sep. 01, 2019
Schedule Of Stockholders Equity [Line Items]    
Number of stock unit received   1
Deferred stock units 14,451  
Director [Member]    
Schedule Of Stockholders Equity [Line Items]    
Director compensation expense related to grants $ 34,649