Commitments and Contingencies (Details 4) (Mexico, USD $) In Millions, unless otherwise specified	Sep. 30, 2012
Minimum
Income Tax Examination
Aggregate potential tax assessments range	$ 90
Income tax examination range of possible losses per year	6
Maximum
Income Tax Examination
Aggregate potential tax assessments range	95
Income tax examination range of possible losses per year	$ 26

The estimated range of reasonably possible losses resulting from an adverse position taken by a taxing authority.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 14

-Paragraph 3

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (d)(3)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

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Data Type:	xbrli:monetaryItemType
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