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Stock-Based Compensation - Summary of Activity Relating to Restricted Stock Units (Detail) - Restricted Stock Units [Member] - shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Outstanding, Shares at beginning balance 82,700  
Granted, Shares 393,539 32,500
Vested, Shares (82,128)  
Forfeited, Shares (60,868)  
Outstanding, Shares at ending balance 333,243