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Employee Future Benefits - Assumptions (Details) | 12 Months Ended
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Dec. 31, 2023 age | Dec. 31, 2023 Rate | Dec. 31, 2022 Rate
Other, through 2027 |  |  |
Assumed health-care cost trend rate |  |  |
Health-care cost escalation | 4.50% | 4.50% |
Maximum age disabled and retired members eligible for benefits | 65 | 65 |
Percentage of reasonably possible decrease in actuarial assumption | 0.30% | 0.30% |
Other Post-Employment Benefit Plans, through 2032 |  |  |
Assumed health-care cost trend rate |  |  |
Health-care cost escalation | 4.50% | 4.50% | 450.00%
Maximum age disabled and retired members eligible for benefits |  | 65 | 65
Percentage of reasonably possible decrease in actuarial assumption | 0.30% | 0.30% | 30.00%
Other Post-Employment Benefit Plans, through 2032 | Canada |  |  |
Assumed health-care cost trend rate |  |  |
Health-care cost escalation | 4.50% | 4.50% | 450.00%
Other, 2030 through 2031 |  |  |
Assumed health-care cost trend rate |  |  |
Health-care cost escalation |  |  | 450.00%
Maximum age disabled and retired members eligible for benefits |  |  | 65
Percentage of reasonably possible decrease in actuarial assumption |  |  | 30.00%
Other, 2030 through 2031 | Canada |  |  |
Assumed health-care cost trend rate |  |  |
Health-care cost escalation |  |  | 4.50%
Accrued Benefit Obligation | Registered |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Discount rate | 4.60% | 4.60% | 4.70%
Rate of compensation increase | 2.90% | 2.90% | 2.60%
Assumed health-care cost trend rate |  |  |
Health-care cost escalation | 0.00% | 0.00% | 0.00%
Dental-care cost escalation | 0.00% | 0.00% | 0.00%
Accrued Benefit Obligation | Supplemental |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Discount rate | 4.60% | 4.60% | 5.00%
Rate of compensation increase | 3.00% | 3.00% | 3.00%
Assumed health-care cost trend rate |  |  |
Health-care cost escalation | 0.00% | 0.00% | 0.00%
Dental-care cost escalation | 0.00% | 0.00% | 0.00%
Accrued Benefit Obligation | Other, through 2027 |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Discount rate | 4.70% | 4.70% | 5.00%
Rate of compensation increase | 0.00% | 0.00% | 0.00%
Assumed health-care cost trend rate |  |  |
Health-care cost escalation | 6.80% | 6.80% | 7.10%
Dental-care cost escalation | 4.20% | 4.20% | 4.20%
Other, through 2027 | Registered |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Discount rate | 5.00% | 5.00% | 2.80%
Rate of compensation increase | 2.70% | 2.70% | 2.90%
Assumed health-care cost trend rate |  |  |
Health-care cost escalation | 0.00% | 0.00% | 0.00%
Dental-care cost escalation | 0.00% | 0.00% | 0.00%
Other, through 2027 | Supplemental |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Discount rate | 5.00% | 5.00% | 2.80%
Rate of compensation increase | 3.00% | 3.00% | 3.00%
Assumed health-care cost trend rate |  |  |
Health-care cost escalation | 0.00% | 0.00% | 0.00%
Dental-care cost escalation | 0.00% | 0.00% | 0.00%
Other, through 2027 | Other, through 2027 |  |  |
Disclosure of defined benefit plans [line items] |  |  |
Discount rate | 5.00% | 5.00% | 2.70%
Rate of compensation increase | 0.00% | 0.00% | 0.00%
Assumed health-care cost trend rate |  |  |
Health-care cost escalation | 7.10% | 7.10% | 6.80%
Dental-care cost escalation | 4.70% | 4.70% | 4.70%

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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 salary increases 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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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. + References No definition available. + Details
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- Definition The reasonably possible percentage of the decrease in the actuarial assumption used to determine the present value of defined benefit obligation. [Refer: Actuarial assumptions [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IAS -Number 19 -IssueDate 2023-01-01 -Paragraph 145 -Subparagraph a -URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_145_a&doctype=Standard -URIDate 2023-03-23 + Details
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