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Financial Instruments - Summary of Other Financial Assets and Other Financial Liabilities Positions (Detail) - EUR (€) € in Millions | Dec. 31, 2017 | Dec. 31, 2016
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Disclosure of detailed information about financial instruments [line items] |  |
Non-current derivative financial assets | € 29 | € 49
Current derivative financial assets | 67 | 51
Derivatives assets | 96 | 100
Non-current loans | 81 |
Current loans | 2 | 66
Loans | 83 | 66
Other non-current financial assets | 110 | 49
Other current financial assets | 69 | 117
Other financial assets | 179 | 166
Other non-current financial liabilities | 43 | 30
Other current financial liabilities | 23 | 34
Other financial liabilities | 66 | 64
Non-current derivative financial liabilities | 43 | 30
Current derivative financial liabilities | 23 | 34
Derivatives Liabilities | 66 | 64
Aluminium and premium future contract [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non-current derivative financial assets | 6 |
Current derivative financial assets | 39 | 6
Derivatives assets | 45 | 6
Non-current derivative financial liabilities |  | 4
Current derivative financial liabilities | 6 | 5
Derivatives Liabilities | 6 | 9
Energy future contract [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Current derivative financial assets |  | 4
Derivatives assets |  | 4
Other future contract [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Current derivative financial assets | 1 |
Derivatives assets | 1 |
Current derivative financial liabilities | 1 | 2
Derivatives Liabilities | 1 | 2
Currency commercial contracts [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non-current derivative financial assets | 21 | 2
Current derivative financial assets | 20 | 11
Derivatives assets | 41 | 13
Non-current derivative financial liabilities | 6 | 26
Current derivative financial liabilities | 12 | 27
Derivatives Liabilities | 18 | 53
Currency net debt derivatives [member] |  |
Disclosure of detailed information about financial instruments [line items] |  |
Non-current derivative financial assets | 2 | 47
Current derivative financial assets | 7 | 30
Derivatives assets | 9 | € 77
Non-current derivative financial liabilities | 37 |
Current derivative financial liabilities | 4 |
Derivatives Liabilities | € 41 |

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- Definition The amount of non-derivative financial assets with fixed or determinable payments that are not quoted in an active market, other than: (a) those that the entity intends to sell immediately or in the near term, which shall be classified as held for trading, and those that the entity, upon initial recognition, designates as at fair value through profit or loss; (b) those that the entity, upon initial recognition, designates as available for sale; or (c) those for which the holder may not recover substantially all of its initial investment, other than because of credit deterioration, which shall be classified as available for sale. An interest acquired in a pool of assets that are not loans or receivables (for example, an interest in a mutual fund or a similar fund) is not a loan or receivable. [Refer: Derivative financial assets] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Note Expiry date 2018-01-01 -Name IFRS -Number 7 -IssueDate 2017-01-01 -Paragraph 8 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_8_c&doctype=Standard&book=B -URIDate 2017-03-09 + Details
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