Goodwill, Service Contracts and Other Assets - Information Regarding Service Contracts and Other Assets (Details) - USD ($) $ in Thousands	Aug. 31, 2019	May 31, 2019
Information regarding service contracts and other assets
Service contracts, net	$ 482,977	$ 494,595
Other assets, carrying amount	395,032	369,630
Other assets, accumulated amortization	149,967	129,315
Other assets, net	245,065	240,315
Capitalized contract costs
Information regarding service contracts and other assets
Other assets, carrying amount	301,854	277,016
Other assets, accumulated amortization	89,840	71,062
Other assets, net	212,014	205,954
Other assets current	71,300	69,600
Noncompete and consulting agreements
Information regarding service contracts and other assets
Other assets, carrying amount	42,494	42,308
Other assets, accumulated amortization	40,740	40,524
Other assets, net	1,754	1,784
Other
Information regarding service contracts and other assets
Other assets, carrying amount	50,684	50,306
Other assets, accumulated amortization	19,387	17,729
Other assets, net	31,297	32,577
Service Contracts
Information regarding service contracts and other assets
Service contracts, carrying amount	931,682	928,635
Service contracts, accumulated amortization	448,705	434,040
Service contracts, net	$ 482,977	$ 494,595