Goodwill, Service Contracts and Other Assets - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 28, 2019	Feb. 28, 2018	Feb. 28, 2019	Feb. 28, 2018
Goodwill, Service Contracts and Other Assets [Abstract]
Amortization expense for service contracts and other assets	$ 33.7	$ 15.7	$ 99.9	$ 45.5
Estimated amortization expense, year one	134.3		134.3
Estimated amortization expense, year two	128.3		128.3
Estimated amortization expense, year three	113.2		113.2
Estimated amortization expense, year four	101.1		101.1
Estimated amortization expense, year five	82.9		82.9
Estimated amortization expense, thereafter	$ 329.4		$ 329.4