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Share-Based Compensation - Additional Information (Detail) - shares
3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Share-based compensation arrangement by share-based payment award, equity Instruments other than options, grants in period 0 0
Employee Stock Purchase Plan    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Stock issued during period, shares, employee stock purchase plans 0 0