Leases - Additional Cash Flow Information Related to Leases (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 41.9	$ 46.2
Operating cash flows from finance leases	0.9	0.8
Financing cash flows from finance leases	7.5	7.6
Right-of-use assets obtained in exchange for new operating leases	21.6	11.6
Right-of-use assets obtained in exchange for new finance leases	$ 17.9	$ 11.5