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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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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-Topic 230
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Goodwill And Other Intangible Assets Goodwill and Other Intangible Assets (Rollforward Schedule of Identifiable Intangibles) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Feb. 15, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	$ 36,295
PE Films [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	730	$ 845		$ 959
Amortization	(115)	(114)
Flexible Packaging Films [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	2,811	3,528		24,033
Amortization	(436)	(2,954)
Finite Lived Intangible Assets, Foreign Currency Translation Gain (Loss)	(281)	(51)
Impairment of Intangible Assets, Finite-lived		(17,500)
Aluminum Extrusions [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	32,754	36,179	$ 30,700	8,609
Amortization	(3,425)	(3,130)
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	22,785	25,444
Customer Relationships [Member] \| PE Films [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	0	0		0
Amortization	0	0
Customer Relationships [Member] \| Flexible Packaging Films [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	661	831		12,084
Amortization	(82)	(1,793)
Finite Lived Intangible Assets, Foreign Currency Translation Gain (Loss)	(88)	(16)
Impairment of Intangible Assets, Finite-lived	(9,444)	(9,444)
Customer Relationships [Member] \| Aluminum Extrusions [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	22,124	24,613	24,000	2,760
Amortization	(2,489)	(2,147)
Proprietary Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	1,093	1,700
Proprietary Technology [Member] \| PE Films [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	730	845		959
Amortization	(115)	(114)
Proprietary Technology [Member] \| Flexible Packaging Films [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	288	360		5,574
Amortization	(55)	(1,161)
Finite Lived Intangible Assets, Foreign Currency Translation Gain (Loss)	(17)	(2)
Impairment of Intangible Assets, Finite-lived	(4,051)	(4,051)
Proprietary Technology [Member] \| Aluminum Extrusions [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	75	495	0	1,049
Amortization	(420)	(554)
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	12,417	13,408
Trade Names [Member] \| PE Films [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	0	0		0
Amortization	0	0
Finite Lived Intangible Assets, Foreign Currency Translation Gain (Loss)	(176)	(33)
Impairment of Intangible Assets, Finite-lived	(4,005)	(4,005)
Trade Names [Member] \| Flexible Packaging Films [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	1,862	2,337		6,375
Amortization	(299)
Trade Names [Member] \| Aluminum Extrusions [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	10,555	11,071	$ 6,700	$ 4,800
Amortization	$ (516)	$ (429)