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Segmented Information - Share of E-Car Partnership (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Segment Reporting Information [Line Items] |  |  |
Total sales | $ 30,837 | $ 28,748 | $ 23,465
E-Car [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Total sales | 91 | 92 | 20
Total adjusted EBIT loss | $ 130 | $ 91 | $ 89

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- Definition Adjusted income loss before interest and income taxes. + References No definition available. + Details
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- Definition Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Article 5 + Details
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