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ACQUISITION OF CONSTELLIUM-BOWLING GREEN - Narrative (Details) - EUR (€) € in Millions |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jan. 09, 2019 | Dec. 31, 2019 | Dec. 31, 2020 | Jan. 10, 2019
Disclosure of detailed information about business combination [line items] |  |  |  |
Preexisting trade receivables with acquiree |  | € 393 | € 341 |
Constellium-UACJ ABS LLC |  |  |  |
Disclosure of detailed information about business combination [line items] |  |  |  |
Percentage of voting equity interest acquired |  |  |  | 49.00%
Consideration transferred |  |  |  | € 87
Fair value of previously held interest |  |  |  | 69
Preexisting trade receivables with acquiree |  |  |  | 38
Goodwill |  |  |  | € 24
Acquisition-related costs recognized as expense in other gains / (losses) |  | 1 |  |
Combined revenue |  | 333 |  |
Combined net loss |  | € 48 |  |
Constellium-UACJ ABS LLC |  |  |  |
Disclosure of detailed information about business combination [line items] |  |  |  |
Proportion of ownership interest in joint venture | 51.00% |  |  |

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- Definition The amount of acquisition-related costs recognised as an expense for transactions that are recognised separately from the acquisition of assets and the assumption of liabilities in business combinations. [Refer: Business combinations [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2020-01-01 -Paragraph B64 -Subparagraph m -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2020-en-r&anchor=para_B64_m&doctype=Appendix&subtype=B -URIDate 2020-01-01 + Details
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- Definition The fair value, at acquisition date, of cash transferred as consideration in a business combination. [Refer: Business combinations [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 3 -IssueDate 2020-01-01 -Paragraph B64 -Subparagraph f -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2020-en-r&anchor=para_B64_f_i&doctype=Appendix&subtype=B -URIDate 2020-01-01 + Details
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