Quarterly report pursuant to Section 13 or 15(d)

Employee Benefit Plan - Additional Information (Detail)

v3.3.1.900
Employee Benefit Plan - Additional Information (Detail) - Employee Savings Plan - USD ($)
3 Months Ended 6 Months Ended
Nov. 30, 2015
Nov. 30, 2014
Nov. 30, 2015
Nov. 30, 2014
Defined Contribution Plan Disclosure [Line Items]        
Qualified non-elective contribution 3.00%      
Qualified non-elective contribution expense $ 5,700 $ 4,600 $ 5,700 $ 4,900