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Revenue - Summary of Revenue by Product Line (Detail) - EUR (€) € in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Disclosure of products and services [line items] |  |  |  |
Revenue | € 1,474 | € 1,382 | € 2,860 | € 2,710
Packaging rolled products [member] |  |  |  |
Disclosure of products and services [line items] |  |  |  |
Revenue | 589 | 566 | 1,125 | 1,116
Automotive rolled products [member] |  |  |  |
Disclosure of products and services [line items] |  |  |  |
Revenue | 163 | 123 | 318 | 227
Specialty and other thin-rolled products [member] |  |  |  |
Disclosure of products and services [line items] |  |  |  |
Revenue | 47 | 45 | 92 | 94
Aerospace rolled products [member] |  |  |  |
Disclosure of products and services [line items] |  |  |  |
Revenue | 197 | 207 | 376 | 408
Transportation, Industry and other rolled products [member] |  |  |  |
Disclosure of products and services [line items] |  |  |  |
Revenue | 148 | 151 | 300 | 287
Automotive extruded products [member] |  |  |  |
Disclosure of products and services [line items] |  |  |  |
Revenue | 178 | 151 | 347 | 309
Other extruded products [member] |  |  |  |
Disclosure of products and services [line items] |  |  |  |
Revenue | 148 | 136 | 296 | 262
Other [member] |  |  |  |
Disclosure of products and services [line items] |  |  |  |
Revenue | € 4 | € 3 | € 6 | € 7

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