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Cash and Cash Equivalents (Tables) | 12 Months Ended
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Dec. 31, 2018
Text block [abstract] |
Summary of Cash and Cash Equivalents |
(in millions of Euros) |  | At December 31, 2018 |  |  | At December 31, 2017 |
Cash in bank and on hand |  |  | 164 |  |  |  | 269 |
Total Cash and cash equivalents |  |  | 164 |  |  |  | 269 |

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