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Shares Repurchased - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Oct. 29, 2014
Equity, Class of Treasury Stock [Line Items]        
Repurchased common stock, value $ 24,116,000 $ 6,531,000 $ 1,613,000  
Three-Year Share Repurchase Program [Member]        
Equity, Class of Treasury Stock [Line Items]        
Common stock purchase authorized amount       $ 100,000,000
Repurchased common stock, shares 1,190      
Repurchased common stock, value $ 24,116,000      
Repurchased shares, remaining for future purchases $ 75,884,000      
Three-Year Share Repurchase Program [Member] | Tax Withholding Obligations [Member]        
Equity, Class of Treasury Stock [Line Items]        
Repurchased common stock, shares   416 137  
Repurchased common stock, value   $ 6,531,000 $ 1,613,000