Employee Benefit Plan - Additional Information (Detail) - Employee Savings Plan - USD ($)	3 Months Ended		6 Months Ended
	Nov. 30, 2016	Nov. 30, 2015	Nov. 30, 2016	Nov. 30, 2015
Defined Contribution Plan Disclosure [Line Items]
Qualified non-elective contribution			3.00%
Qualified non-elective contribution expense	$ 9,800	$ 5,700	$ 18,600	$ 5,700