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FINANCIAL RISK MANAGEMENT - Effect of Foreign Currency Derivatives Impacts and Commercial Transactions Exposures (Details) - EUR (€) € in Millions | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Realized gains / (losses) on foreign currency derivatives - net | € (1) | € (11) | € 1
Unrealized (losses) / gains on foreign currency derivatives - net | 13 | (8) | 1
Losses reclassified from OCI as a result of hedge accounting discontinuation | 0 | 6 | 0
Derivatives that do not qualify for hedge accounting | At fair value through profit and loss |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Realized gains / (losses) on foreign currency derivatives - net | 1 | (4) | 7
Unrealized (losses) / gains on foreign currency derivatives - net | 15 | (9) | 2
Derivatives that qualify for hedge accounting | At fair value through profit and loss |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Realized gains / (losses) on foreign currency derivatives - net | (2) | (7) | (6)
Unrealized (losses) / gains on foreign currency derivatives - net | (2) | 1 | (1)
Losses reclassified from OCI as result of hedge accounting discontinuation | 0 | (6) | 0
Losses reclassified from OCI as a result of hedge accounting discontinuation |  | 6 |
Derivatives that qualify for hedge accounting | At fair value through OCI |  |  |
Disclosure of nature and extent of risks arising from financial instruments [line items] |  |  |
Unrealized (losses) / gains on foreign currency derivatives - net | (21) | 20 | (15)
Gains reclassified from cash flow hedge reserve to the Consolidated Income Statement | € 4 | € 6 | € 7

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- Definition Unrealized gains (losses) on foreign currency derivatives - net. + References No definition available. + Details
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