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Stockholders' Equity - Additional Information (Detail) - USD ($)
 12 Months Ended
Nov. 05, 2015
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Jun. 02, 2016
Stockholders Equity [Line Items]          
Value of shares that have been repurchased and retired during the period   $ 21,489,000 $ 26,532,000    
Payment for share repurchase   $ 21,489,000 $ 26,532,000 $ 4,367,000  
2016 Stock Repurchase Program          
Stockholders Equity [Line Items]          
Board of Directors authorized stock repurchase program         $ 100,000,000
Number of shares that have been repurchased and retired during the period   452,300      
Average price per share   $ 41.06      
Value of shares that have been repurchased and retired during the period   $ 18,600,000      
Available amount under repurchase program   81,400,000      
Payment for share repurchase   $ 18,600,000      
2015 Stock Repurchase Program          
Stockholders Equity [Line Items]          
Board of Directors authorized stock repurchase program $ 50,000,000        
Number of shares that have been repurchased and retired during the period   85,100 764,545    
Average price per share   $ 34.16 $ 34.68    
Value of shares that have been repurchased and retired during the period   $ 2,900,000 $ 26,532,000    
Payment for share repurchase   $ 2,900,000 $ 26,532,000    
Stock repurchase program, period 6 months        
Stock repurchase program expiration date   May 05, 2016