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Stock-Based Compensation - Performance-based Equity Awards - Additional Information (Detail) - shares
3 Months Ended
Mar. 31, 2017
Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Unvested performance units 274,500 296,500
Performance Based Equity Awards [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Unvested units forfeitures 22,000