Goodwill, Service Contracts and Other Assets - Estimated Future Amortization Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Nov. 30, 2020	Nov. 30, 2019	Nov. 30, 2020	Nov. 30, 2019
Goodwill, Service Contracts And Other Assets [Abstract]
Amortization expense for service contracts and other assets	$ 35,400	$ 35,300	$ 70,500	$ 69,900
2021 (remaining six months)	69,901		69,901
2022	130,427		130,427
2023	111,191		111,191
2024	99,082		99,082
2025	86,188		86,188
Thereafter	250,294		250,294
Total future amortization expense	$ 747,083		$ 747,083