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CURRENCY GAINS / (LOSSES) - Currency Gains and Losses Included in Income from Operations (Details) € in Millions, $ in Millions | 12 Months Ended
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Dec. 31, 2020 EUR (€) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 EUR (€) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 EUR (€) | Dec. 31, 2018 USD ($)
Analysis of income and expense [line items] |  |  |  |  |  |
Total currency gains / (losses) - net | € (27) | $ (27) | € 3 | $ 3 | € 11 | $ 11
Realized exchange (losses) / gains on foreign currency derivatives - net | (11) |  | 1 |  | 11 |
Losses reclassified from OCI as a result of hedge accounting discontinuation | (6) |  | 0 |  | 0 |
Unrealized (losses) / gains on foreign currency derivatives - net | (8) |  | 1 |  | (3) |
Exchange (losses) / gains from the remeasurement of monetary assets and liabilities - net | (2) |  | 1 |  | 3 |
Included in Revenue |  |  |  |  |  |
Analysis of income and expense [line items] |  |  |  |  |  |
Total currency gains / (losses) - net | (6) |  | (7) |  | 2 |
Included in Cost of sales |  |  |  |  |  |
Analysis of income and expense [line items] |  |  |  |  |  |
Total currency gains / (losses) - net | (2) |  | 1 |  | 2 |
Included in Other gains and losses - net |  |  |  |  |  |
Analysis of income and expense [line items] |  |  |  |  |  |
Total currency gains / (losses) - net | € (19) |  | € 9 |  | € 7 |

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- Definition Exchanges gains / (losses) from remeasurement of monetary assets and liabilities - net. + References No definition available. + Details
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- Definition The gain (loss) recognised in profit or loss on hedge ineffectiveness. [Refer: Gain (loss) on hedge ineffectiveness] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 24C -Subparagraph a -Clause i -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_24C_a_i&doctype=Standard -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 7 -IssueDate 2020-01-01 -Paragraph 24C -Subparagraph b -Clause ii -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_24C_b_ii&doctype=Standard -URIDate 2020-01-01 + Details
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- Definition The amount of exchange differences recognised in profit or loss that arise from foreign currency transactions, excluding those arising on financial instruments measured at fair value through profit or loss in accordance with IFRS 9. [Refer: At fair value [member]; Financial instruments, class [member]] + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 7 -IssueDate 2020-01-01 -Section A Statement of cash flows for an entity other than a financial institution -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=7&code=ifrs-tx-2020-en-r&doctype=Illustrative%20Examples&dita_xref=IAS07_IE_A_TI -URIDate 2020-01-01 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 21 -IssueDate 2020-01-01 -Paragraph 52 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=21&code=ifrs-tx-2020-en-r&anchor=para_52_a&doctype=Standard -URIDate 2020-01-01 + Details
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