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v3.19.1

Intangible Assets (Including Goodwill) - Additional Information (Detail) - EUR (€) € in Millions |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 31, 2018 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Disclosure of reconciliation of changes in intangible assets and goodwill [line items] |  |  |  |
Goodwill | € 422 | € 422 | € 403 | € 457
P&ARP [member] |  |  |  |
Disclosure of reconciliation of changes in intangible assets and goodwill [line items] |  |  |  |
Goodwill | € 415 | 415 |  |
Cash flow projected period | 7 years |  |  |
Carrying value | € 1,354 | 1,354 |  |
Recoverable value | € 1,716 | € 1,716 |  |
Increase discount rate |  | 2.25% |  |
Decrease in the perpetual growth |  | 4.00% |  |
Automotive Body Sheet lower shipments |  | 45.00% |  |
P&ARP [member] | Bottom of range [member] |  |  |  |
Disclosure of reconciliation of changes in intangible assets and goodwill [line items] |  |  |  |
Growth rate, cash flows projections | 0.00% | 0.00% |  |
Discount rate, cash flows projections | 10.00% | 10.00% |  |
P&ARP [member] | Top of range [member] |  |  |  |
Disclosure of reconciliation of changes in intangible assets and goodwill [line items] |  |  |  |
Growth rate, cash flows projections | 1.50% | 1.50% |  |
Discount rate, cash flows projections | 12.00% | 12.00% |  |
A&T [member] |  |  |  |
Disclosure of reconciliation of changes in intangible assets and goodwill [line items] |  |  |  |
Goodwill | € 5 | € 5 |  |
AS&I [member] |  |  |  |
Disclosure of reconciliation of changes in intangible assets and goodwill [line items] |  |  |  |
Goodwill | € 2 | € 2 |  |

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