Derivative Financial Instruments (Schedule of Notional Amounts of Outstanding Derivative Positions) (Details) - Futures	9 Months Ended
Sep. 30, 2017 T
Aluminum \| Long
Derivative [Line Items]
Commodity contract (in MT/Lbs)	1,275
Aluminum \| Short
Derivative [Line Items]
Commodity contract (in MT/Lbs)	2,250
Copper \| Long
Derivative [Line Items]
Commodity contract (in MT/Lbs)	4,251
Copper \| Short
Derivative [Line Items]
Commodity contract (in MT/Lbs)	21,727

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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