Segment Reporting (Schedule Of Identifiable Assets By Segment) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Subtotal	$ 532,943	$ 569,458
General corporate	85,934	111,788
Cash, cash equivalents, and restricted cash at beginning of period	39,930	31,422	$ 39,769	$ 34,397
Total assets	658,807	712,668
PE Films
Total assets	226,027	230,415
Flexible Packaging Films [Member] [Domain]
Total assets	66,011	74,016
Aluminum Extrusions [Member]
Total assets	$ 240,905	$ 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
-Topic 230
-SubTopic 10
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