BUSINESS SEGMENTS - Segment EBITDA (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 116,351	$ 108,560
Segment adjusted EBITDA	130,258	122,336
Gain on sale of building	547	10,852
Income before taxes	60,142	68,020
Operating Segments
Segment Reporting Information [Line Items]
Depreciation and amortization	(14,690)	(16,973)
Operating Segments | Home and Building Products
Segment Reporting Information [Line Items]
Adjusted EBITDA	124,719	124,145
Depreciation and amortization	(3,633)	(3,846)
Operating Segments | Consumer and Professional Products
Segment Reporting Information [Line Items]
Adjusted EBITDA	5,539	(1,809)
Depreciation and amortization	(11,057)	(13,127)
Segment Reconciling Items
Segment Reporting Information [Line Items]
Unallocated amounts, excluding depreciation	(13,907)	(13,776)
Net interest expense	(24,875)	(24,544)
Depreciation and amortization	(14,823)	(17,113)
Restructuring charges	(12,400)	0
Gain on sale of building	547	10,852
Strategic review - retention and other	(4,658)	(8,232)
Proxy expenses	$ 0	$ (1,503)