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Operating Segment Information - Summary of Segment adjusted EBITDA and reconciliation of Adjusted EBITDA to Net Income (Parenthetical) (Detail) - EUR (€) € in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jul. 31, 2018 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Disclosure of segment adjusted EBITDA and reconciliation of adjusted EBITDA to net income [line items] |  |  |  |
Start-up costs and development cost |  | € (21) | € (17) | € (25)
Wise one-time cost |  |  |  | (20)
Cash received from Wise purchase price adjustment |  |  |  | 21
Wise purchase price adjustment |  |  |  | 20
Gains / (Losses) on pension plans amendments |  | 36 | 20 |
Collective Bargaining agreement renegotiation [member] |  |  |  |
Disclosure of segment adjusted EBITDA and reconciliation of adjusted EBITDA to net income [line items] |  |  |  |
Legal fees and lump-sum payments |  |  | € 3 |
Collective bargaining agreement term |  |  | 5 years |
AS&I [member] |  |  |  |
Disclosure of segment adjusted EBITDA and reconciliation of adjusted EBITDA to net income [line items] |  |  |  |
Start-up costs and development cost |  | € 21 | € 16 |
Automotive Body Sheet Growth Projects [member] |  |  |  |
Disclosure of segment adjusted EBITDA and reconciliation of adjusted EBITDA to net income [line items] |  |  |  |
Start-up costs and development cost |  |  |  | € 20
Disposal of leased assets [member] | Novelis [member] |  |  |  |
Disclosure of segment adjusted EBITDA and reconciliation of adjusted EBITDA to net income [line items] |  |  |  |
Sale of assets | € 200 |  |  |
Net gain on sale of assets | € 190 |  |  |

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- Definition Disclosure of segment adjusted EBITDA and reconciliation of adjusted EBITDA to net income. + References No definition available. + Details
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- Definition Gains (losses) on pension plan amendments. + References No definition available. + Details
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- Definition The cash inflow from the disposal of property, plant and equipment, intangible assets other than goodwill, investment property and other non-current assets. [Refer: Intangible assets other than goodwill; Investment property; Other non-current assets; Property, plant and equipment] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 7 -IssueDate 2018-01-01 -Paragraph 16 -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=7&date=2018-03-01&anchor=para_16&doctype=Standard -URIDate 2018-03-16 + Details
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- Details
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