PROPERTY, PLANT AND EQUIPMENT - Schedule of Property, Plant and Equipment (Details) - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023
Property, Plant and Equipment [Line Items]
Finance leases	$ 141.4	$ 136.9
Property, plant and equipment	734.7	704.7
Accumulated depreciation	(468.1)	(429.6)
Property, plant and equipment, net	266.6	275.1
Land, buildings and improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	88.2	83.4
Machinery, tooling and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	337.4	330.1
Computer software
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	142.6	136.2
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 25.1	$ 18.1