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SHARE-BASED COMPENSATION - Additional Information (Details) - EUR (€) € in Millions | 6 Months Ended
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Jun. 30, 2020 | Jun. 30, 2019
Share Based Payment Plans [line items] |  |
Total expense related to the potential ordinary shares | € 8 | € 7
PSUs |  |
Share Based Payment Plans [line items] |  |
Share based compensation vesting period | 3 years |
PSUs | Bottom of range |  |
Share Based Payment Plans [line items] |  |
Percentage of vesting multiplier | 0.00% |
PSUs | Top of range |  |
Share Based Payment Plans [line items] |  |
Percentage of vesting multiplier | 200.00% |
RSUs |  |
Share Based Payment Plans [line items] |  |
Share based compensation vesting period | 3 years |

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- Definition Share based compensation vesting period. + References No definition available. + Details
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- Definition The amount of expense from share-based payment transactions with employees. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2019-01-01 -Paragraph 112 -Subparagraph c -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2019-en-r&anchor=para_112_c&doctype=Standard -URIDate 2019-03-27 + Details
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- Details
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- Details
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