PROPERTY, PLANT AND EQUIPMENT - Schedule of Property Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Sep. 30, 2025
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	$ 706,678	$ 697,206
Accumulated depreciation	(413,583)	(403,678)
Total	293,095	293,528
Land, building and building improvements
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	161,634	160,233
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	506,678	498,656
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	38,366	38,317
Construction in Progress
Property, Plant and Equipment [Line Items]
Machinery and equipment	$ 23,236	$ 33,239