Summary of Significant Accounting Policies Concentration (Details)	12 Months Ended
Dec. 31, 2014
Supplier Concentration Risk [Member]
Concentration Risk [Line Items]
Vendors Accounting for More Than Ten Percent of Aluminum Purchases	2

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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