Segment Reporting (Schedule Of Segment Reporting Information By Segment) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Segment Reporting Information [Line Items]
Assets	$ 635,763		$ 623,260
Total net sales	200,332	$ 226,846
Add back freight	7,001	7,325
Sales as shown in the Consolidated Statements of Income	207,333	234,171
Total Segment Income (Loss)	18,624	22,961
Interest income	37	89
Interest expense	1,085	885
Gain on investment accounted for under fair value method	800	0
Stock option-based compensation costs	(37)	300
Corporate expenses, net	7,916	7,216
Income from continuing operations before income taxes	10,497	14,649
Income taxes from continuing operations	3,216	4,779
Net income	7,281	9,870
kaleo
Segment Reporting Information [Line Items]
Assets	138,044		120,452
Gain on investment accounted for under fair value method	800	0
Income taxes from continuing operations	8	4
Net income	(6,139)	(11,868)
PE Films
Segment Reporting Information [Line Items]
Assets	276,940		270,236
Total net sales	88,481	106,357
Operating profit from ongoing operations	10,235	16,832
Plant shutdowns, asset impairments, restructurings and other	(1,135)	0
Flexible Packaging Films [Member] [Domain]
Segment Reporting Information [Line Items]
Assets	155,000		146,253
Total net sales	26,377	26,844
Operating profit from ongoing operations	2,032	785
Plant shutdowns, asset impairments, restructurings and other	0	67
Aluminum Extrusions
Segment Reporting Information [Line Items]
Assets	135,726		$ 136,935
Total net sales	85,474	93,645
Operating profit from ongoing operations	7,499	5,292
Plant shutdowns, asset impairments, restructurings and other	$ (7)	$ (15)