Pensions (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended		12 Months Ended
		Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Mar. 31, 2026
Net Periodic Benefit Cost [Abstract]
Net periodic benefit cost	[1]	$ 1.1	$ 0.9	$ 2.3	$ 1.7
Pension [Member]
Net Periodic Benefit Cost [Abstract]
Service cost		0.1	0.0	0.1	0.1
Interest cost		2.2	2.4	4.5	4.8
Expected return on plan assets		(2.1)	(2.6)	(4.3)	(5.2)
Amortization of unrecognized net loss		1.1	1.2	2.3	2.3
Net periodic benefit cost		1.3	$ 1.0	2.6	$ 2.0
Pension [Member] | U.S Plans [Member]
Employer Contributions [Abstract]
Cash contributions by employer				6.5
Pension [Member] | U.S Plans [Member] | Minimum [Member]
Termination of U.S. Pension Plans [Abstract]
Expected employer contribution during fiscal 2026		10.0		10.0
Pension [Member] | U.S Plans [Member] | Maximum [Member]
Termination of U.S. Pension Plans [Abstract]
Expected employer contribution during fiscal 2026		$ 25.0		$ 25.0
Pension [Member] | U.S Plans [Member] | Plan [Member] | Minimum [Member]
Termination of U.S. Pension Plans [Abstract]
Non-cash pension settlement charges						$ (120.0)
Pension [Member] | U.S Plans [Member] | Plan [Member] | Maximum [Member]
Termination of U.S. Pension Plans [Abstract]
Non-cash pension settlement charges						$ (130.0)

[1] Net periodic benefit cost for the Company’s pension and postretirement plans is exclusive of service cost.