XML 55 R42.htm IDEA: XBRL DOCUMENT v3.5.0.2
Stock-Based Compensation - Additional Information (Detail)
3 Months Ended
Aug. 31, 2016
USD ($)
$ / shares
shares
Non-Qualified Stock Options  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Non-qualified stock options, granted | shares 111,000
Non-qualified stock option, per share price | $ / shares $ 42.30
Non-qualified stock option, fair value, per share price | $ / shares $ 11.60
Pre-tax stock-based compensation | $ $ 1,146,000
Pre-tax stock-based compensation, period of recognition 3 years
Service-Based Restricted Common Shares  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Pre-tax stock-based compensation, period of recognition 3 years
Performance share awards granted | shares 115,625
Restricted common shares, fair value per share | $ / shares $ 42.30
Pre-tax stock-based compensation | $ $ 4,353,000
Performance Shares  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Pre-tax stock-based compensation, period of recognition 3 years
Performance share awards granted | shares 68,500
Pre-tax stock-based compensation | $ $ 2,809,000