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Derivatives (Outstanding Commodity Futures Contracts) (Details) - lb lb in Millions | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Copper [Member] | Not Designated as Hedging Instrument [Member] |  |
Derivative [Line Items] |  |
Notional Amounts | 1.8 | 2.4
Copper [Member] | Cash Flow Hedging [Member] |  |
Derivative [Line Items] |  |
Notional Amounts | 20.6 | 30.4
Aluminum [Member] | Not Designated as Hedging Instrument [Member] |  |
Derivative [Line Items] |  |
Notional Amounts | 1.8 | 2.6

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- Definition Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract. + References 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 + Details
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- Details
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- Details
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