The calculated weighted-average amortization period (in months) of a major class of finite-lived intangible assets acquired during the current period either individually or as part of a group of assets (in either an asset acquisition or business combination). A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of a company.

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The amount of acquisition cost of a business combination allocated to an identifiable intangible asset that will be amortized.

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Acquisitions (Details 2) (Alcan Packaging Food Americas, USD $)	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Mar. 02, 2010
Acquired finite-lived intangible assets
Estimated amortization expense	$ 5,300,000	$ 7,400,000
Fair value			130,300,000
Customer relationships
Acquired finite-lived intangible assets
Useful life (in years)	20
Fair value			87,300,000
Technology based
Acquired finite-lived intangible assets
Useful life (in years)	15
Fair value			39,700,000
Order backlog
Acquired finite-lived intangible assets
Useful life (in months)	1
Fair value			$ 3,300,000