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Acquisitions and Divestitures - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified | 0 Months Ended | 3 Months Ended | 9 Months Ended |  | 0 Months Ended | 1 Months Ended |
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Jun. 25, 2014 | Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013 | Jun. 25, 2014 | Jun. 25, 2014 Firth Rixson [Member] | Aug. 31, 2014 Firth Rixson [Member] | Jun. 25, 2014 Firth Rixson [Member]
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Business acquisition purchase price |  |  |  |  |  |  | $ 2,850 |  |
Cash paid for business acquisition |  |  |  |  |  |  | 2,350 |  |
Value of common stock issued |  |  |  |  |  |  | 500 |  |
Business acquisition potential earn-out |  |  |  |  |  |  |  |  | 150
Common stock issued as part of acquisition | 36,523,010 |  |  |  |  |  | 36,523,010 |  |
Business acquisition common stock issued, price per share |  |  |  |  |  | $ 13.69 |  |  | $ 13.69
Business acquisition, unsecured bridge term loan |  |  |  |  |  |  |  |  | 2,500
Interest expenses |  | 126 | 108 | 351 | 341 |  | 13 |  |
Interest expenses, after tax |  |  |  |  |  |  | 8 |  |
Percentage of acquisition of outstanding noncontrolling interest |  |  |  |  |  |  |  | 30.00% |
Acquisition of outstanding noncontrolling interest, amount paid |  |  |  |  |  |  |  | 28 |
Difference between purchase price and carrying value of noncontrolling interest |  |  |  |  |  |  |  | $ 3 |

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- Definition Short-Term financing which is expected to be paid back relatively quickly, such as by a subsequent longer-term loan. Also called swing loan or bridge financing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 + Details
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