Derivatives (Outstanding Contracts Designated as Cash Flow Hedges) (Details) - Designated as Hedging Instrument [Member] lb in Millions, MXN in Millions	Mar. 31, 2016 MXN lb	Dec. 31, 2015 MXN lb
Commodity Futures Contracts [Member] \| Copper [Member]
Derivative [Line Items]
Derivative, nonmonetary notional amount (in lbs) \| lb	32.4	34.7
Foreign Exchange Forward [Member] \| Mexican Peso [Member]
Derivative [Line Items]
Derivative, notional amount \| MXN	MXN 151.6	MXN 201.4

- 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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Namespace Prefix:	invest_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- 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

Name:	invest_DerivativeNotionalAmount
Namespace Prefix:	invest_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- 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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- Details

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- Details

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- Details

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- Details

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