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Financial Instruments Financial Instruments (Summary of Location and Fair Value of Currency Forward Derivative Financial Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Net asset (liability)	$ (1,254)	$ (487)
Cost of Goods and Services Sold	649,690	558,967	$ 641,140
Aluminum Futures Contracts [Member]
Derivatives, Fair Value [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	6,215	74	(2,359)
Aluminum Futures Contracts [Member] \| Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Net asset (liability)	1,966
Aluminum Futures Contracts [Member] \| Designated as Hedging Instrument [Member] \| Prepaid Expenses and Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	2,085
Derivative Liability, Fair Value, Gross Liability	119
Aluminum Futures Contracts [Member] \| Designated as Hedging Instrument [Member] \| Accrued Expenses [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset		1,560
Derivative Liability, Fair Value, Gross Liability		22
Flexible Packaging Films [Member] [Domain]
Derivatives, Fair Value [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	0	0	0
Flexible Packaging Films [Member] [Domain] \| Selling, General and Administrative Expenses [Member]
Derivatives, Fair Value [Line Items]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	(2,415)	(4,437)	(856)
Flexible Packaging Films [Member] [Domain] \| Designated as Hedging Instrument [Member] \| Accrued Expenses [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	853
Derivative Liability, Fair Value, Gross Liability	(1,255)	(466)
Foreign Currency Forward Contracts \| Selling, General and Administrative Expenses [Member] \| Reclassification out of Accumulated Other Comprehensive Income [Member] \| Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Derivatives, Fair Value [Line Items]
Cost of Goods and Services Sold	$ (337)	$ (6,069)	$ (904)