Goodwill, Service Contracts and Other Assets - Information Regarding Service Contracts and Other Assets (Details) - USD ($) $ in Thousands	Aug. 31, 2020	May 31, 2020
Information regarding service contracts and other assets
Service contracts, net	$ 441,641	$ 451,529
Other assets, carrying amount	505,944	474,041
Other assets, accumulated amortization	234,365	213,283
Other assets, net	271,579	260,758
Capitalized contract costs
Information regarding service contracts and other assets
Other assets, carrying amount	399,204	375,912
Other assets, accumulated amortization	169,248	148,853
Other assets, net	229,956	227,059
Other assets current	77,500	76,200
Noncompete and consulting agreements
Information regarding service contracts and other assets
Other assets, carrying amount	44,174	43,890
Other assets, accumulated amortization	41,621	41,317
Other assets, net	2,553	2,573
Other
Information regarding service contracts and other assets
Other assets, carrying amount	62,566	54,239
Other assets, accumulated amortization	23,496	23,113
Other assets, net	39,070	31,126
Service Contracts
Information regarding service contracts and other assets
Service contracts, carrying amount	948,118	941,383
Service contracts, accumulated amortization	506,477	489,854
Service contracts, net	$ 441,641	$ 451,529