PROPERTY, PLANT AND EQUIPMENT - Summary of Property Plant and Equipment (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Sep. 30, 2021
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	$ 749,521	$ 715,597
Accumulated depreciation and amortization	(449,677)	(425,375)
Total	299,844	290,222
Land, building and building improvements
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	154,187	155,574
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	550,899	520,110
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	$ 44,435	$ 39,913