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Investments Accounted for Under Equity Method - Summary of Amounts Included in Consolidated Financial Statements in Accordance with Group Accounting Principles (Parenthetical) (Detail) - EUR (€) € in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Disclosure of investments accounted for using equity method [line items] |  |
Gain related shareholders loan facilities modification | € 11 |
Share of losses of joint-ventures in excess of initial investment | 49 |
Group Companies and Constellium UACJ ABS LLC [member] |  |
Disclosure of investments accounted for using equity method [line items] |  |
Loans | 118 | € 97
Share of losses of joint-ventures in excess of initial investment | € 49 | € 14

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- Definition Cumulative share of profit (loss) of joint ventures accounted for using equity method. + References No definition available. + Details
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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 Gain on shareholders loan facilities modification. + References No definition available. + Details
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- Definition Loans to joint ventures. + References No definition available. + Details
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- Details
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