REPORTABLE SEGMENTS - Segment EBITDA (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 118,525	$ 134,231	$ 249,717	$ 250,582
Segment adjusted EBITDA	133,160	149,045	278,394	279,303
Gain on sale of real estate	183	11	8,157	558
Strategic review - retention and other	(1,199)	(2,676)	(2,850)	(7,334)
Income before taxes	78,637	88,573	176,057	148,715
Operating Segments
Segment Reporting Information [Line Items]
Depreciation and amortization	(15,512)	(14,943)	(31,005)	(29,633)
Operating Segments \| Home and Building Products
Segment Reporting Information [Line Items]
Adjusted EBITDA	109,434	128,924	236,476	253,643
Depreciation and amortization	(4,334)	(3,772)	(8,609)	(7,405)
Operating Segments \| Consumer and Professional Products
Segment Reporting Information [Line Items]
Adjusted EBITDA	23,726	20,121	41,918	25,660
Depreciation and amortization	(11,178)	(11,171)	(22,396)	(22,228)
Segment Reconciling Items
Segment Reporting Information [Line Items]
Unallocated amounts, excluding depreciation	(14,635)	(14,814)	(28,677)	(28,721)
Net interest expense	(23,222)	(25,512)	(47,703)	(50,387)
Depreciation and amortization	(15,650)	(15,080)	(31,264)	(29,903)
Restructuring charges	0	(2,401)	0	(14,801)
Gain on sale of real estate	183	11	8,157	558
Strategic review - retention and other	$ (1,199)	$ (2,676)	$ (2,850)	$ (7,334)

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