Business Segments (Schedule Of Depreciation And Amortization, Capital Expenditures) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Capital Expenditures	$ 14,347	$ 26,446	$ 36,875
Amortization of identifiable intangibles	2,313	2,865	2,444
Capital Expenditure, Discontinued Operations	2,489	4,323	8,151
Operating Segments
Segment Reporting Information [Line Items]
Depreciation and Amortization	25,537	27,683	26,402
Capital Expenditures	14,347	26,446	36,875
PE Films \| Operating Segments
Segment Reporting Information [Line Items]
Depreciation and Amortization	5,200	6,522	6,280
Capital Expenditures	1,761	1,772	3,289
Aluminum Extrusions \| Operating Segments
Segment Reporting Information [Line Items]
Depreciation and Amortization	17,722	17,927	17,414
Capital Expenditures	10,097	20,339	23,664
Subtotal
Segment Reporting Information [Line Items]
Depreciation and Amortization	22,922	24,449	23,694
Subtotal \| Operating Segments
Segment Reporting Information [Line Items]
Depreciation and Amortization	22,922	24,449	23,694
Capital Expenditures	11,858	22,111	26,953
General corporate \| Operating Segments
Segment Reporting Information [Line Items]
Depreciation and Amortization	302	369	264
Capital Expenditures	$ 0	$ 12	$ 1,771

Amount of capital expenditure attributable to discontinued operations.

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Amount of deprecation and amortization expense attributable to property, plant and equipment and intangible assets of discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
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Amount of expense charged against earnings to allocate the cost of tangible and intangible assets over their remaining economic lives, classified as other.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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