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Acquisitions and Divestitures - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended |  | 12 Months Ended | 1 Months Ended | 12 Months Ended
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Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2012 Russia [Member] Facility | Dec. 31, 2011 TransDigm Group Inc [Member] Employees | Dec. 31, 2010 TransDigm Group Inc [Member] | Dec. 31, 2011 TransDigm Group Inc [Member] California [Member] Location | Dec. 31, 2011 TransDigm Group Inc [Member] United Kingdom [Member] Location | Jul. 31, 2010 Traco [Member] Employees | Dec. 31, 2011 Traco [Member] | Dec. 31, 2010 Traco [Member] | Dec. 31, 2010 Transportation Products Europe [Member] Employees | Dec. 31, 2010 Transportation Products Europe [Member] Divestiture [Member] Location | Dec. 31, 2012 Three Hundred Fifty One Megawatt Tapoco Hydroelectric Project [Member] acre ElectricStation mi | Dec. 31, 2012 Three Hundred Fifty One Megawatt Tapoco Hydroelectric Project [Member] Primary Metals Segment [Member] | Dec. 31, 2012 Three Hundred Fifty One Megawatt Tapoco Hydroelectric Project [Member] Corporate [Member]
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from divestiture of businesses |  |  |  |  |  |  |  |  |  |  | $ 14 |  | $ 597 |  |
Gain (loss) on sale of business |  |  |  |  |  |  |  |  |  |  |  |  | 320 | 426 | (106)
Gain (loss) on sale of business, after tax |  |  |  |  |  |  |  |  |  |  |  |  | 173 | 275 | (102)
Number of hydroelectric generating stations and dams |  |  |  |  |  |  |  |  |  |  |  |  | 4 |  |
Length of transmission line |  |  |  |  |  |  |  |  |  |  |  |  | 86 |  |
Acres of land associated with divestitures |  |  |  |  |  |  |  |  |  |  |  |  | 14,500 |  |
Allocation of goodwill |  |  |  |  |  |  |  |  |  |  |  |  | (94) |  |
Business acquisition cost |  | 240 |  |  |  |  |  |  |  | 77 |  |  |  |  |
Cash acquired and post-closing adjustments resulted in net purchase price |  | 239 |  |  |  |  |  |  |  |  |  |  |  |  |
Number of employees |  |  |  | 400 |  |  |  | 650 |  |  | 360 |  |  |  |
Number of business locations |  |  |  |  |  | 1 | 2 |  |  |  |  | 2 |  |  |
Sales generated in last annual period prior to divestiture |  |  |  |  | 61 |  |  |  |  |  | 78 |  |  |  |
Amount of goodwill recorded | 154 |  |  |  |  |  |  |  |  | 28 |  |  |  |  |
Amount of reduction in the initial goodwill amount | 1 |  |  |  |  |  |  |  | 4 |  |  |  |  |  |
Amount of goodwill is estimated to be deductible for income tax purposes | 60 |  |  |  |  |  |  |  | 24 |  |  |  |  |  |
Sales generated prior year before acquisition |  |  |  |  |  |  |  |  |  | 100 |  |  |  |  |
Additional amount to settle working capital |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |
Gain from divestiture |  |  |  |  |  |  |  |  |  |  | 5 |  |  |  |
Gain from divestiture, pretax |  |  |  |  |  |  |  |  |  |  | 5 |  |  |  |
Additional contingent consideration payable | $ 50 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of facilities acquired |  |  | 2 |  |  |  |  |  |  |  |  |  |  |  |

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