XML 56 R45.htm IDEA: XBRL DOCUMENT v3.19.2
Shareholders' Equity - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended
Jun. 10, 2019
Apr. 30, 2019
Apr. 30, 2018
Jun. 04, 2019
Aug. 22, 2017
Equity, Class of Treasury Stock [Line Items]          
Common shares authorized for repurchase, shares         20,000,000
Remaining common shares authorized for repurchase, shares   11,971,326      
Stock repurchased and retired during period, total cost   $ (76,625) $ (5,047)    
Employee Stock          
Equity, Class of Treasury Stock [Line Items]          
Stock repurchased and retired during period, common shares   176,081 138,310    
Stock repurchased and retired during period, total cost   $ 5,383 $ 5,047    
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 5,637,369        
Stock repurchased and retired during period, total cost $ 146,180        
Average cost per share, including commissions $ 25.93