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Shareholders' Equity - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
 6 Months Ended
Sep. 06, 2017
Jul. 31, 2017
Aug. 22, 2017
Feb. 23, 2015
Equity, Class of Treasury Stock [Line Items]        
Common shares authorized for repurchase, shares       20,000,000
Remaining common shares authorized for repurchase, shares   985,354    
Stock repurchased and retired during period, total cost   $ 91,653    
Employee Stock        
Equity, Class of Treasury Stock [Line Items]        
Stock repurchased and retired during period, common shares   43,423    
Stock repurchased and retired during period, total cost   $ 1,142    
Subsequent Event        
Equity, Class of Treasury Stock [Line Items]        
Common shares authorized for repurchase, shares     20,000,000  
Stock repurchased and retired during period, common shares 1,500,000      
Stock repurchased and retired during period, total cost $ 30,841      
Average cost per share $ 20.56      
February 23, 2015 Authorization | Subsequent Event        
Equity, Class of Treasury Stock [Line Items]        
Stock repurchased and retired during period, common shares 985,354      
August 22, 2017 Authorization | Subsequent Event        
Equity, Class of Treasury Stock [Line Items]        
Stock repurchased and retired during period, common shares 514,646