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PENSION AND OTHER POST-EMPLOYMENT BENEFIT OBLIGATIONS - Actuarial Assumptions (Details) | Dec. 31, 2023 | Dec. 31, 2022
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OPEB | Pre 65 | 2024 |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Medical trend rate | 7.90% |
OPEB | Pre 65 | 2032 and Onward |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Medical trend rate | 4.50% |
Switzerland |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Rate of increase in salaries | 1.75% | 1.75%
Rate of increase in pensions | 0.00% | 0.00%
Discount rate | 1.40% | 2.05%
U.S. | Hourly pension |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Rate of increase in salaries | 3.00% | 3.00%
Rate of increase in pensions | 0.00% | 0.00%
U.S. | Hourly pension | Bottom of range |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Discount rate | 4.85% | 5.00%
U.S. | Hourly pension | Top of range |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Discount rate | 4.90% | 5.05%
U.S. | Salaried pension |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Rate of increase in salaries | 0.00% | 0.00%
Rate of increase in pensions | 0.00% | 0.00%
Discount rate | 4.85% | 5.05%
U.S. | OPEB |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Rate of increase in salaries | 4.00% | 4.00%
Rate of increase in pensions | 0.00% | 0.00%
U.S. | OPEB | Bottom of range |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Discount rate | 4.85% | 5.00%
U.S. | OPEB | Top of range |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Discount rate | 4.90% | 5.05%
U.S. | Other benefits |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Rate of increase in salaries | 3.80% | 3.80%
Rate of increase in pensions | 0.00% | 0.00%
U.S. | Other benefits | Bottom of range |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Discount rate | 4.75% | 4.95%
U.S. | Other benefits | Top of range |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Discount rate | 4.85% | 5.00%
France |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Rate of increase in salaries | 2.10% |
Rate of increase in pensions | 2.00% | 2.00%
France | Bottom of range |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Rate of increase in salaries |  | 2.20%
France | Retirements |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Rate of increase in salaries | 0.00% | 0.00%
Rate of increase in pensions | 0.00% | 0.00%
Discount rate | 3.30% | 3.80%
France | Other benefits |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Rate of increase in salaries | 0.00% | 0.00%
Rate of increase in pensions | 0.00% | 0.00%
Discount rate | 3.25% | 3.80%
Germany |  |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |  |
Rate of increase in salaries | 2.50% | 2.50%
Rate of increase in pensions | 2.00% | 2.00%
Discount rate | 3.30% | 3.75%

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- Definition The discount rate used as the significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2023-01-01 -Paragraph 144 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_144&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition The expected rate of increases in pension that is used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit plans [member]; Defined benefit obligation, at present value; Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2023-01-01 -Paragraph 144 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_144&doctype=Standard -URIDate 2023-03-23 + Details
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- Definition Medical cost trend rate used as significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 19 -IssueDate 2023-01-01 -Paragraph 144 -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_144&doctype=Standard -URIDate 2023-03-23 + Details
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