Revenue Recognition - Contract Assets, Liabilities and Performance Obligations (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended		12 Months Ended
	Feb. 28, 2025	Aug. 31, 2024	May 31, 2024	Feb. 29, 2024	Feb. 28, 2025	Feb. 29, 2024	May 31, 2024
Contract assets and liabilities
Contract assets - current	$ 153.3		$ 123.2		$ 153.3		$ 123.2
Contract assets - non-current	31.2		24.6		31.2		24.6
Contract liabilities:
Deferred revenue - current	(41.5)		(14.7)		(41.5)		(14.7)
Deferred revenue on long-term contracts	(9.7)		(7.2)		(9.7)		(7.2)
Net contract assets	133.3		125.9		133.3		125.9
Change in contract assets - current					30.1
Change in contract assets - non-current					6.6
Change in deferred revenue - current					(26.8)
Change in deferred revenue on long-term contracts					(2.5)
Change in net contract assets					7.4
Change in contract assets and revenue					37.8	$ (0.5)
Accounts receivable, net	312.5		287.2		312.5		287.2
Impairment charges					63.0
Changes in deferred revenue
Deferred revenue at beginning of period	(29.6)	$ (21.9)	(22.3)	$ (26.4)	(21.9)	(32.4)	(32.4)
Revenue deferred	(101.8)			(86.4)	(271.8)	(222.6)
Revenue recognized	81.8			85.6	243.5	228.0
Other	(1.6)			4.9	(1.0)	4.7
Deferred revenue at end of period	(51.2)		(21.9)	$ (22.3)	(51.2)	$ (22.3)	(21.9)
Remaining Performance Obligations
Remaining performance obligation	$ 590.0				$ 590.0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-03-01
Remaining Performance Obligations
Remaining performance obligation (as a percent)	75.00%				75.00%
Expected timing of satisfaction of remaining performance obligation	12 months				12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-03-01
Remaining Performance Obligations
Remaining performance obligation (as a percent)	20.00%				20.00%
Expected timing of satisfaction of remaining performance obligation	12 months				12 months
Termination settlement proposal
Contract liabilities:
Contract assets with customer	$ 13.5				$ 13.5
Termination amount for equipment and other costs	1.0
Air Line Customers | Termination Of Power By The Hour Program
Contract liabilities:
Termination charge			4.8
Change in contract assets and revenue							7.8
Change in contract revenue							7.8
Repair reserves			2.5				2.5
Obligation to purchase the rotable assets							5.5
Asset purchase obligation of purchase price			$ 20.9				$ 20.9
Accounts receivable, net	14.9				14.9
Contract assets with customer	10.0				10.0
Air Line Customers | Termination Of Power By The Hour Program | Past Due
Contract liabilities:
Accounts receivable, net	$ 7.8				$ 7.8
U.S. Government Customer | Next Generation Pallet Contract
Contract liabilities:
Contract assets with customer		9.5
Equipment and inventory expensed		$ 12.7