BUSINESS SEGMENTS - Segment EBITDA (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Segment Reporting Information [Line Items]
Adjusted EBITDA	$ 125,494	$ 138,613	$ 376,076	$ 384,049
Segment adjusted EBITDA	140,779	152,595	420,082	426,437
Loss from debt extinguishment	(1,700)	0	(1,700)	0
Gain (loss) on sale of buildings	(725)	0	(167)	10,852
Strategic review - retention and other	(1,870)	(5,812)	(9,204)	(20,234)
Proxy expenses		(568)		(2,685)
Intangible asset impairment	0	0	0	(100,000)
Special dividend ESOP charges		9,042		9,042
Income before taxes	61,009	78,453	209,724	56,314
Operating Segments
Segment Reporting Information [Line Items]
Depreciation and amortization	(15,108)	(15,529)	(44,741)	(49,616)
Operating Segments | Home and Building Products
Segment Reporting Information [Line Items]
Adjusted EBITDA	118,516	134,330	372,159	390,346
Depreciation and amortization	(3,883)	(3,868)	(11,288)	(11,525)
Operating Segments | Consumer and Professional Products
Segment Reporting Information [Line Items]
Adjusted EBITDA	22,263	18,265	47,923	36,091
Depreciation and amortization	(11,225)	(11,661)	(33,453)	(38,091)
Segment Reconciling Items
Segment Reporting Information [Line Items]
Unallocated amounts, excluding depreciation	(15,285)	(13,982)	(44,006)	(42,388)
Net interest expense	(26,255)	(25,207)	(76,642)	(74,394)
Depreciation and amortization	(15,247)	(15,669)	(45,150)	(50,036)
Loss from debt extinguishment	(1,700)	0	(1,700)	0
Restructuring charges	(18,688)	(3,862)	(33,489)	(82,196)
Gain (loss) on sale of buildings	(725)	0	(167)	10,852
Strategic review - retention and other	(1,870)	(5,812)	(9,204)	(20,234)
Proxy expenses	0	(568)	0	(2,685)
Intangible asset impairment	0	0	0	(100,000)
Special dividend ESOP charges	$ 0	$ 9,042	$ 0	$ (9,042)