Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 28, 2026	Feb. 28, 2025	Feb. 28, 2026	Feb. 28, 2025
Accumulated Other Comprehensive Loss
Balance, beginning	$ 1,561.2	$ 1,181.6	$ 1,211.6	$ 1,189.8
Balance, ending	1,643.4	1,182.6	1,643.4	1,182.6
Currency Translation Adjustments
Accumulated Other Comprehensive Loss
Balance, beginning	(3.2)	(7.3)	(2.4)	(5.5)
Other comprehensive income (loss)	1.7	(1.5)	0.9	(3.3)
Balance, ending	(1.5)	(8.8)	(1.5)	(8.8)
Pension Plans
Accumulated Other Comprehensive Loss
Balance, beginning	(3.2)	(3.3)	(3.2)	(3.3)
Balance, ending	(3.2)	(3.3)	(3.2)	(3.3)
Total
Accumulated Other Comprehensive Loss
Balance, beginning	(6.4)	(10.6)	(5.6)	(8.8)
Other comprehensive income (loss)	1.7	(1.5)	0.9	(3.3)
Balance, ending	$ (4.7)	$ (12.1)	$ (4.7)	$ (12.1)