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Proposed Separation Transaction - Additional Information (Detail) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2016 USD ($) | Jun. 30, 2016 USD ($)
Arconic Inc [Member] |  |
Proposed Separation Transaction [Line Items] |  |
Percentage of shares retained | 19.90% | 19.90%
Selling, General Administrative, and Other Expenses [Member] |  |
Proposed Separation Transaction [Line Items] |  |
Costs related to proposed transaction, pre-tax | $ 45 | $ 63
Costs related to proposed transaction, after-tax | $ 37 | $ 54

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- Definition Proposed separation transaction costs before tax. + References No definition available. + Details
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- Definition Proposed separation transaction costs net of tax. + References No definition available. + Details
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- Definition Proposed Separation Transaction [Line Items] + References No definition available. + Details
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571 + Details
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- Details
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- Details
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