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OPERATING SEGMENT INFORMATION - Segment Revenue (Details) - EUR (€) € in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Disclosure of operating segments [line items] |  |  |
Revenue | € 4,883 | € 5,907 | € 5,686
P&ARP |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | 2,725 | 3,139 | 3,050
A&T |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | 1,002 | 1,420 | 1,339
AS&I |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | 1,156 | 1,348 | 1,287
H&C |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | 0 | 0 | 10
Segment revenue |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | 4,926 | 5,962 | 5,748
Segment revenue | P&ARP |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | 2,734 | 3,149 | 3,059
Segment revenue | A&T |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | 1,025 | 1,462 | 1,389
Segment revenue | AS&I |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | 1,167 | 1,351 | 1,290
Segment revenue | H&C |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | 0 | 0 | 10
Inter-segment elimination |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | (43) | (55) | (62)
Inter-segment elimination | P&ARP |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | (9) | (10) | (9)
Inter-segment elimination | A&T |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | (23) | (42) | (50)
Inter-segment elimination | AS&I |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | (11) | (3) | (3)
Inter-segment elimination | H&C |  |  |
Disclosure of operating segments [line items] |  |  |
Revenue | € 0 | € 0 | € 0

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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Definition The amount of revenue from contracts with customers. A customer is a party that has contracted with an entity to obtain goods or services that are an output of the entity’s ordinary activities in exchange for consideration. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2020-01-01 -Paragraph 113 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2020-en-r&anchor=para_113_a&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 15 -IssueDate 2020-01-01 -Paragraph 114 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2020-en-r&anchor=para_114&doctype=Standard -URIDate 2020-01-01 + Details
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