Goodwill And Other Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Goodwill [Line Items]
Goodwill impairment charge	$ 0	$ 13,696	$ 0
Goodwill, Impairment Loss, Net of Tax		10,500
Goodwill	70,608	67,708	81,404
Loss on sale of divested businesses	0	52,326	0
Flexible Packaging Films [Member]
Goodwill [Line Items]
Amortization	(392)	(397)
PE Films [Member]
Goodwill [Line Items]
Amortization	0	(120)
Goodwill impairment charge	0	0
Goodwill	57,338	57,338	57,338
Aluminum Extrusions
Goodwill [Line Items]
Amortization	(2,259)	(2,500)
Goodwill impairment charge	0	13,696	0
Goodwill	13,270	10,370	24,066
Loss on sale of divested businesses		(10,000)
Impairment of Intangible Assets, Finite-lived	0	0	$ 10,040
Adjustment to accumulated amortization of customer relationship intangible	(900)
Reclassification from customer relationship intangibles to goodwill	(2,900)
Reclassification from customer relationship intangibles to goodwill	2,900
Adjustment to accumulated amortization of customer relationship intangible	(900)
Customer Relationships [Member] \| Flexible Packaging Films [Member]
Goodwill [Line Items]
Amortization	(82)	(84)
Customer Relationships [Member] \| PE Films [Member]
Goodwill [Line Items]
Amortization	0	0
Customer Relationships [Member] \| Aluminum Extrusions
Goodwill [Line Items]
Amortization	(2,239)	(2,480)
Proprietary Technology [Member] \| Flexible Packaging Films [Member]
Goodwill [Line Items]
Amortization	(53)	(53)
Proprietary Technology [Member] \| PE Films [Member]
Goodwill [Line Items]
Amortization	0	(120)
Proprietary Technology [Member] \| Aluminum Extrusions
Goodwill [Line Items]
Amortization	(20)	(20)
Trade Names [Member] \| Flexible Packaging Films [Member]
Goodwill [Line Items]
Amortization	(257)	(260)
Trade Names [Member] \| PE Films [Member]
Goodwill [Line Items]
Amortization	0	0
Trade Names [Member] \| Aluminum Extrusions
Goodwill [Line Items]
Amortization	$ 0	$ 0

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The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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