Leases - Operating Lease Cost and Additional Lease Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Aug. 31, 2021	Aug. 31, 2020	May 31, 2021
Leases [Abstract]
Operating lease costs	$ 18,200	$ 17,100
Other information related to operating leases
Cash paid for amounts included in the measurement of operating lease liabilities	11,913	12,254
Operating lease right-of-use assets obtained in exchange for new and renewed operating lease liabilities	$ 2,792	$ 9,317
Weighted-average remaining lease term - operating leases	5 years 2 months 19 days		5 years 3 months 29 days
Weighted-average discount rate - operating leases	2.29%		2.32%