Financial Instruments (Narrative) (Details) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014 USD ($) lb	Dec. 31, 2013 lb	Dec. 31, 2014 Aluminum Futures Contracts USD ($)	Dec. 31, 2013 Aluminum Futures Contracts USD ($)	Dec. 31, 2013 Film Products EUR (€)
Derivative [Line Items]
Notional amount			$ 8.6	$ 8.0	€ 2.1
Weight of aluminum that hedged future purchase of aluminum to meet fixed-price forward sales contract obligations, lbs	7,800,000	8,400,000
Amounts of unrealized after-tax gains on derivative instruments	$ 0.2

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

+ Details

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- Definition

Nominal mass used to calculate payments on a derivative instrument.

+ References

No definition available.

+ Details

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