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GOODWILL AND INTANGIBLE ASSETS - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 26, 2026	Jun. 27, 2025	Jun. 26, 2026	Jun. 27, 2025	Apr. 30, 2026	Mar. 27, 2026	Feb. 10, 2025
Goodwill [Line Items]
Held-for-sale, goodwill							$ 756
Goodwill, divestiture			$ 1,488
Intangible asset amortization	$ 3,608	$ 10,108	16,201	$ 31,972
Disposal Group, Held-for-Sale, Not Discontinued Operations \| HDPE Business
Goodwill [Line Items]
Held-for-sale, goodwill						$ 6,500
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Vergo G&C
Goodwill [Line Items]
Held-for-sale, goodwill					$ 1,506
Goodwill, divestiture			1,488
Electrical
Goodwill [Line Items]
Accumulated impairment loss	12,145		12,145
Goodwill, divestiture			1,488
Safety & Infrastructure
Goodwill [Line Items]
Accumulated impairment loss	$ 61,885		61,885
Goodwill, divestiture			$ 0