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FINANCIAL INSTRUMENTS - Derivatives Measured at Fair Value (Details) - EUR (€) € in Millions | Jun. 30, 2021 | Dec. 31, 2020
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Disclosure of financial instruments measured at fair value [line items] |  |
Other financial assets - derivatives | € 79 | € 57
Other financial liabilities - derivatives | 36 | 87
Level 1 |  |
Disclosure of financial instruments measured at fair value [line items] |  |
Other financial assets - derivatives | 44 | 20
Other financial liabilities - derivatives | 8 | 9
Level 2 |  |
Disclosure of financial instruments measured at fair value [line items] |  |
Other financial assets - derivatives | 35 | 37
Other financial liabilities - derivatives | 28 | 78
Level 3 |  |
Disclosure of financial instruments measured at fair value [line items] |  |
Other financial assets - derivatives | 0 | 0
Other financial liabilities - derivatives | € 0 | € 0

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- Definition Disclosure of financial instruments measured at fair value. + References No definition available. + Details
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- Definition The amount of financial assets classified as derivative instruments. [Refer: Financial assets; Derivatives [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_55&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_55&doctype=Standard -URIDate 2020-01-01 + Details
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