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Derivatives (Outstanding Contracts Designated as Cash Flow Hedges) (Details) - Designated as Hedging Instrument [Member] lb in Millions, $ in Millions, $ in Millions | Mar. 31, 2018 CAD ($) lb | Mar. 31, 2018 MXN ($) lb | Dec. 31, 2017 CAD ($) lb | Dec. 31, 2017 MXN ($) lb
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Commodity Contract - Copper [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, nonmonetary notional amount (in lbs) | lb | 20.2 | 20.2 | 20.6 | 20.6
Commodity Contract - Aluminum [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, nonmonetary notional amount (in lbs) | lb | 16.6 | 16.6 | 0.0 | 0.0
Foreign Exchange Forward [Member] | Mexican Peso [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, notional amount | $ |  | $ 152.2 |  | $ 207.3
Foreign Exchange Forward [Member] | Canadian Dollar [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative, notional amount | $ | $ 51.0 |  | $ 68.6 |

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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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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + 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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- Definition 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. + References No definition available. + Details
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- Details
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