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Segmented Information - Additional Information (Detail) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2012 Center Operations Markets Employee Country | Aug. 31, 2012
Segment Reporting Information [Line Items] |  |
Number of manufacturing operations | 313 |
Number of product development, engineering and sales centres | 88 |
Number of countries in which entity operates | 29 |
Number of employees | 119,000 |
Number of primary markets | 2 |
Interest acquired in E-Car partnership |  | 27.00%
E-Car [Member] |  |
Segment Reporting Information [Line Items] |  |
Interest acquired in E-Car partnership |  | 27.00%
Percentage of non-controlling interest in an equity accounted investment | 73.00% |

X
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