Segment Reporting (Schedule Of Identifiable Assets By Segment) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Subtotal	$ 543,700	$ 569,458
General corporate	84,427	111,788
Cash, cash equivalents, and restricted cash at beginning of period	35,059	31,422	$ 36,302	$ 34,397
Total assets	663,186	712,668
PE Films
Total assets	224,987	230,415
Flexible Packaging Films [Member] [Domain]
Total assets	65,869	74,016
Aluminum Extrusions [Member]
Total assets	$ 252,844	$ 265,027

Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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