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PENSION AND OTHER POST-EMPLOYMENT BENEFIT OBLIGATIONS - Narrative (Details) - EUR (€) € in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Oct. 31, 2022 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2018
Disclosure of defined benefit plans [line items] |  |  |  |  |
Collective bargaining agreement, period | 3 years |  |  |  |
Increase (reduction) in pension obligation |  | € 0 | € (47) |  |
Gains on pension plan amendments |  | € 0 | € 47 | € (32) |
Weighted-average maturity of defined benefit obligations |  | 11 years 6 months | 11 years 2 months 12 days |  |
Defined benefit obligations |  |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |  |
Increase (reduction) in pension obligation |  | € (4) | € (47) |  |
Other Benefits |  |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |  |
Gains on pension plan amendments |  |  |  |  | € 36
Expected contributions to pension and other benefits for next year |  | 16 |  |  |
Other Benefits | Defined benefit obligations |  |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |  |
Increase (reduction) in pension obligation |  | 0 | (49) |  |
OPEB |  |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |  |
Gains on pension plan amendments |  |  | 49 |  |
Loss recognized on disputes about plan changes |  |  |  | € 31 |
Pension Benefits |  |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |  |
Expected contributions to pension and other benefits for next year |  | 32 |  |  |
Pension Benefits | Defined benefit obligations |  |  |  |  |
Disclosure of defined benefit plans [line items] |  |  |  |  |
Increase (reduction) in pension obligation |  | € (4) | € 2 |  |

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- Definition Gains (losses) on pension plan amendments. + References No definition available. + Details
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- Definition The estimate of the expected contributions to be made to a defined benefit plan for the next annual reporting period. [Refer: Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2023-01-01 -Paragraph 147 -Subparagraph b -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_147_b&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2023-01-01 -Paragraph 148 -Subparagraph d -Clause iii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_148_d_iii&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from past service cost and losses (gains) arising from settlements. [Refer: Decrease (increase) in net defined benefit liability (asset) resulting from gains (losses) arising from settlements; Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2023-01-01 -Paragraph 141 -Subparagraph d -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_141_d&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from past service cost. Past service cost is the change in the present value of the defined benefit obligation for employee service in prior periods, resulting from a plan amendment (the introduction or withdrawal of, or changes to, a defined benefit plan) or a curtailment (a significant reduction by the entity in the number of employees covered by a plan). [Refer: Net defined benefit liability (asset); Defined benefit plans [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2023-01-01 -Paragraph 141 -Subparagraph d -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_141_d&doctype=Standard -URIDate 2023-03-23 + Details
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