Leases - Components of Operating Lease Costs (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	May 31, 2020	May 31, 2020
Leases [Abstract]
Operating lease expense	$ 4,388	$ 11,238
Short-term lease expense	1,707	6,437
Total	$ 6,095	$ 17,675