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Investments Accounted for Under Equity Method - Summary of Guarantees and Commitments (Detail) - Constellium-UACJ ABS LLC [member] - EUR (€) € in Millions | Dec. 31, 2017 | Dec. 31, 2016
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Disclosure of investments accounted for using equity method [line items] |  |
Total Guarantees and commitments given | € 14 | € 34
Financial guarantees [member] |  |
Disclosure of investments accounted for using equity method [line items] |  |
Total Guarantees and commitments given | 11 |
Loan Facility Commitment [Member] |  |
Disclosure of investments accounted for using equity method [line items] |  |
Total Guarantees and commitments given |  | 15
Supplier guarantees [member] |  |
Disclosure of investments accounted for using equity method [line items] |  |
Total Guarantees and commitments given | € 3 | € 19

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- Definition Disclosure Of Investments Accounted For Using Equity Method [Line Items] + References No definition available. + Details
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- Definition The commitments that the entity has relating to its joint ventures as specified in paragraphs B18-B20 of IFRS 12. [Refer: Joint ventures [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 12 -IssueDate 2017-01-01 -Paragraph 23 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2017-03-01&anchor=para_23_a&doctype=Standard -URIDate 2017-03-09 + Details
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- Details
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- Details
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