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OPERATING SEGMENT INFORMATION - Segment Assets (Details) - EUR (€) € in Millions | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | --- | --- | ---
Disclosure of operating segments [line items] |  |  |  |
Total Assets | € 4,129 | € 4,184 |  |
Deferred tax assets | 193 | 185 |  |
Cash and cash equivalents | 439 | 184 | € 164 | € 269
Segment revenue |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Total Assets | 3,440 | 3,786 |  |
Segment revenue | P&ARP |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Total Assets | 1,733 | 1,951 |  |
Segment revenue | A&T |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Total Assets | 765 | 856 |  |
Segment revenue | AS&I |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Total Assets | 668 | 703 |  |
Segment revenue | H&C |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Total Assets | 274 | 276 |  |
Unallocated |  |  |  |
Disclosure of operating segments [line items] |  |  |  |
Deferred tax assets | 193 | 185 |  |
Cash and cash equivalents | 439 | 184 |  |
Other financial assets | € 57 | € 29 |  |

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