Revenue Recognition - Changes in deferred revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 28, 2026	Feb. 28, 2025	Feb. 28, 2026	Feb. 28, 2025
Changes in deferred revenue
Deferred revenue at beginning of period	$ (45.8)	$ (29.6)	$ (46.7)	$ (21.9)
Revenue deferred	(205.5)	(101.8)	(373.2)	(271.8)
Revenue recognized	168.1	81.8	344.4	243.5
Other	(4.5)	(1.6)	(12.2)	(1.0)
Deferred revenue at end of period	$ (87.7)	$ (51.2)	$ (87.7)	$ (51.2)