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PENSION AND OTHER POST-EMPLOYMENT BENEFIT OBLIGATIONS - Movement in Net Defined Benefit Obligations (Details) € in Millions, $ in Millions | 12 Months Ended
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Dec. 31, 2023 EUR (€) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 EUR (€)
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Beginning balance | € 403 | $ 403 | € 599
Current service cost | 19 |  | 28
Interest cost / (income) | 16 |  | 11
Past service cost | 0 |  | (47)
Immediate recognition of losses arising over the year | 1 |  | (5)
Administration expenses | 3 |  | 2
Remeasurements due to: |  |  |
—actual return less interest on plan assets | (21) |  | 107
—changes in financial assumptions | 33 |  | (254)
—changes in demographic assumptions | 0 |  | (1)
—experience losses | 3 |  | (12)
Effects of changes in foreign exchange rates | (4) |  | 20
Benefits paid | (19) |  | (6)
Contributions by the Group | (20) |  | (38)
Contributions by the plan participants | 0 |  | 0
Disposed of through business combination | (3) |  |
Reclassification as liabilities of disposal group classified as held for sale |  |  | (1)
Closing balance | 411 |  | 403
Defined benefit obligations |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Beginning balance | 864 |  | 1,143
Current service cost | 19 |  | 28
Interest cost / (income) | 32 |  | 20
Past service cost | (4) |  | (47)
Immediate recognition of losses arising over the year | 1 |  | (5)
Administration expenses | 0 |  | 0
Remeasurements due to: |  |  |
—actual return less interest on plan assets | 0 |  | 0
—changes in financial assumptions | 33 |  | (254)
—changes in demographic assumptions | 0 |  | (1)
—experience losses | 3 |  | (12)
Effects of changes in foreign exchange rates | 3 |  | 50
Benefits paid | (54) |  | (63)
Contributions by the Group | 0 |  | 0
Contributions by the plan participants | 5 |  | 6
Disposed of through business combination | (3) |  |
Reclassification as liabilities of disposal group classified as held for sale |  |  | (1)
Closing balance | 899 |  | 864
Defined benefit obligations | Pension Benefits |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Beginning balance | 710 |  | 894
Current service cost | 14 |  | 20
Interest cost / (income) | 25 |  | 13
Past service cost | (4) |  | 2
Immediate recognition of losses arising over the year | 0 |  | 0
Administration expenses | 0 |  | 0
Remeasurements due to: |  |  |
—actual return less interest on plan assets | 0 |  | 0
—changes in financial assumptions | 31 |  | (211)
—changes in demographic assumptions | 0 |  | 0
—experience losses | 8 |  | (3)
Effects of changes in foreign exchange rates | 8 |  | 34
Benefits paid | (38) |  | (42)
Contributions by the Group | 0 |  | 0
Contributions by the plan participants | 4 |  | 4
Disposed of through business combination | (2) |  |
Reclassification as liabilities of disposal group classified as held for sale |  |  | (1)
Closing balance | 756 |  | 710
Defined benefit obligations | Other Benefits |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Beginning balance | 154 |  | 249
Current service cost | 5 |  | 8
Interest cost / (income) | 7 |  | 7
Past service cost | 0 |  | (49)
Immediate recognition of losses arising over the year | 1 |  | (5)
Administration expenses | 0 |  | 0
Remeasurements due to: |  |  |
—actual return less interest on plan assets | 0 |  | 0
—changes in financial assumptions | 2 |  | (43)
—changes in demographic assumptions | 0 |  | (1)
—experience losses | (5) |  | (9)
Effects of changes in foreign exchange rates | (5) |  | 16
Benefits paid | (16) |  | (21)
Contributions by the Group | 0 |  | 0
Contributions by the plan participants | 1 |  | 2
Disposed of through business combination | (1) |  |
Reclassification as liabilities of disposal group classified as held for sale |  |  | 0
Closing balance | 143 |  | 154
Plan Assets |  |  |
Disclosure of net defined benefit liability (asset) [line items] |  |  |
Beginning balance | (461) |  | (544)
Current service cost | 0 |  | 0
Interest cost / (income) | (16) |  | (9)
Past service cost | 4 |  | 0
Immediate recognition of losses arising over the year | 0 |  | 0
Administration expenses | 3 |  | 2
Remeasurements due to: |  |  |
—actual return less interest on plan assets | (21) |  | 107
—changes in financial assumptions | 0 |  | 0
—changes in demographic assumptions | 0 |  | 0
—experience losses | 0 |  | 0
Effects of changes in foreign exchange rates | (7) |  | (30)
Benefits paid | 35 |  | 57
Contributions by the Group | (20) |  | (38)
Contributions by the plan participants | (5) |  | (6)
Disposed of through business combination | 0 |  |
Reclassification as liabilities of disposal group classified as held for sale |  |  | 0
Closing balance | € (488) |  | € (461)

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- Definition Immediate recognition actuarial gains (losses) arising from change in assumption recognized in profit (loss). + References No definition available. + Details
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in demographic assumptions that result in remeasurements of the net defined benefit liability (asset). Demographic assumptions deal with matters such as: (a) mortality; (b) rates of employee turnover, disability and early retirement; (c) the proportion of plan members with dependants who will be eligible for benefits; (d) the proportion of plan members who will select each form of payment option available under the plan terms; and (e) claim rates under medical plans. [Refer: 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 c -Clause ii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_141_c_ii&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in financial assumptions that result in remeasurements of the net defined benefit liability (asset). Financial assumptions deal with items such as: (a) the discount rate; (b) benefit levels, excluding any cost of the benefits to be met by employees, and future salary; (c) in the case of medical benefits, future medical costs, including claim handling costs (ie the costs that will be incurred in processing and resolving claims, including legal and adjuster's fees); and (d) taxes payable by the plan on contributions relating to service before the reporting date or on benefits resulting from that service. [Refer: 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 c -Clause iii -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_141_c_iii&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from experience adjustments that result in remeasurements of the net defined benefit liability (asset). Experience adjustments deal with the effects of differences between the previous actuarial assumptions and what has actually occurred. [Refer: Net defined benefit liability (asset)] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2023-01-01 -Paragraph 141 -Subparagraph c -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_141_c&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The amount of expenses that the entity classifies as being administrative. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 26 -IssueDate 2023-01-01 -Paragraph 35 -Subparagraph b -Clause vi -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=26&code=ifrs-tx-2023-en-r&anchor=para_35_b_vi&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 103 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_103&doctype=Standard -URIDate 2023-03-23 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 99 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_99&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The amount of benefits paid or payable for retirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 26 -IssueDate 2023-01-01 -Paragraph 35 -Subparagraph b -Clause v -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=26&code=ifrs-tx-2023-en-r&anchor=para_35_b_v&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from contributions to a defined benefit plan by plan participants. [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 f -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_141_f&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: 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 a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_141_a&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The amount of employer contributions to retirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 26 -IssueDate 2023-01-01 -Paragraph 35 -Subparagraph b -Clause i -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=26&code=ifrs-tx-2023-en-r&anchor=para_35_b_i&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from business combinations and disposals. [Refer: Business combinations [member]; 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 h -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_141_h&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from changes in foreign exchange rates. [Refer: 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 e -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_141_e&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The amount of income or expense arising from interest. [Refer: Interest expense; Interest income] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2023-01-01 -Paragraph 28 -Subparagraph e -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2023-en-r&anchor=para_28_e&doctype=Standard -URIDate 2023-03-23 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2023-01-01 -Paragraph 23 -URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2023-en-r&anchor=para_23&doctype=Standard -URIDate 2023-03-23 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2023-01-01 -Paragraph 85 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_85&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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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from the return on plan assets, excluding amounts included in interest income or expense. The return on plan assets is interest, dividends and other revenue derived from the plan assets, together with realised and unrealised gains or losses on the plan assets, less any costs of managing plan assets and less any tax payable by the plan itself, other than tax included in the actuarial assumptions used to measure the present value of the defined benefit obligation. [Refer: Plan assets [member]; Net defined benefit liability (asset); Actuarial assumptions [member]; Increase (decrease) in net defined benefit liability (asset) resulting from interest expense (income)] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2023-01-01 -Paragraph 141 -Subparagraph c -Clause i -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_141_c_i&doctype=Standard -URIDate 2023-03-23 + Details
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