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Cash Flow Information - Schedule of Cash Paid for Acquisitions Including Non-Controlling Interest (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Supplemental Cash Flow Information [Abstract] |  |  |
Assets acquired | $ 0 | $ 0 | $ 2,003
Liabilities assumed | 0 | 0 | (868)
Equity issued | 0 | 0 | (870)
Working capital adjustment | 0 | (10) | 0
Increase in Arconic’s shareholders’ equity | 0 | 0 | (60)
Cash paid | 0 | (10) | 205
Less: cash acquired | 0 | 0 | 302
Net cash paid | $ 0 | $ (10) | $ (97)

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- Definition Payments to acquire businesses net of cash acquired and noncontrolling interest. + References No definition available. + Details
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- Definition The cash inflow (outflow) associated with the acquisition of business during the period. + References No definition available. + Details
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- Definition Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(4) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 + Details
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- Definition Amount of assets acquired at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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- Definition Amount of liabilities assumed at the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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