BUSINESS SEGMENTS - Schedule of Depreciation and Amortization, Capital Expenditures (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Capital expenditures
Capital expenditures			$ 9,266	$ 5,638
Operating Segments
Depreciation and amortization
Depreciation and amortization	$ 5,441	$ 5,372	10,736	10,897
Capital expenditures
Capital expenditures	4,125	2,681	9,266	5,639
Aluminum Extrusions \| Operating Segments
Depreciation and amortization
Depreciation and amortization	4,199	4,093	8,244	8,319
Capital expenditures
Capital expenditures	3,660	2,386	8,349	4,757
High Performance Films \| Operating Segments
Depreciation and amortization
Depreciation and amortization	1,197	1,230	2,400	2,480
Capital expenditures
Capital expenditures	379	295	831	882
Subtotal
Depreciation and amortization
Depreciation and amortization	5,396	5,323	10,644	10,799
Subtotal \| Operating Segments
Depreciation and amortization
Depreciation and amortization	5,396	5,323	10,644	10,799
General corporate \| Operating Segments
Depreciation and amortization
Depreciation and amortization	45	49	92	98
Capital expenditures
Capital expenditures	$ 86	$ 0	$ 86	$ 0