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Summary Of Significant Accounting Policies - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified | 3 Months Ended | 9 Months Ended | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | ---
Sep. 28, 2014 | Sep. 29, 2013 | Sep. 28, 2014 | Sep. 29, 2013 | Dec. 31, 2013 Termination Of A - 12 Program [Member] | Sep. 28, 2014 Axle Business [Member]
Loss Contingencies [Line Items] |  |  |  |  |  |
Asset Impairment Charges |  |  |  |  |  | $ 106
Loss Contingency, Settlement Agreement, Consideration |  |  |  |  | 198 |
Length of fiscal quarters, weeks |  |  | 0 years 0 months 91 days |  |  |
Net increase in operating earnings from the quarterly impact of revisions in contract | $ 13 | $ 105 | $ 103 | $ 296 |  |
Net increase in operating earnings per share from the quarterly impact of revisions in contract | $ 0.02 | $ 0.19 | $ (0.20) | $ 0.54 |  |

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