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Employee Future Benefits - Assumptions (Details) | 12 Months Ended |
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Dec. 31, 2021 | Dec. 31, 2020
Other, through 2027 |  |
Assumed health-care cost trend rate |  |
Health-care cost escalation(1)(3) | 4.50% |
Maximum age disabled and retired members eligible for benefits | 65 years |
Percentage of reasonably possible decrease in actuarial assumption | 0.30% |
Other, through 2030 |  |
Assumed health-care cost trend rate |  |
Health-care cost escalation(1)(3) | 4.50% | 4.50%
Maximum age disabled and retired members eligible for benefits | 65 years |
Percentage of reasonably possible decrease in actuarial assumption | 0.30% | 0.30%
Other, through 2030 | Canada |  |
Assumed health-care cost trend rate |  |
Health-care cost escalation(1)(3) | 4.50% | 4.50%
Other, 2029 through 2030 |  |
Assumed health-care cost trend rate |  |
Maximum age disabled and retired members eligible for benefits | 65 years |
Other, 2029 through 2030 | Canada |  |
Assumed health-care cost trend rate |  |
Health-care cost escalation(1)(3) |  | 4.50%
Other, 2029 through 2030 | US |  |
Assumed health-care cost trend rate |  |
Health-care cost escalation(1)(3) |  | 4.50%
Percentage of reasonably possible decrease in actuarial assumption |  | 0.30%
Accrued Benefit Obligation | Registered |  |
Disclosure of defined benefit plans [line items] |  |
Discount rate | 2.80% | 2.40%
Rate of compensation increase | 2.90% | 2.90%
Assumed health-care cost trend rate |  |
Health-care cost escalation(1)(3) | 0.00% | 0.00%
Dental-care cost escalation | 0.00% | 0.00%
Accrued Benefit Obligation | Supplemental Pension Plan |  |
Disclosure of defined benefit plans [line items] |  |
Discount rate | 2.80% | 2.30%
Rate of compensation increase | 3.00% | 3.00%
Assumed health-care cost trend rate |  |
Health-care cost escalation(1)(3) | 0.00% | 0.00%
Dental-care cost escalation | 0.00% | 0.00%
Accrued Benefit Obligation | Other, through 2027 |  |
Disclosure of defined benefit plans [line items] |  |
Discount rate | 2.70% | 2.30%
Rate of compensation increase | 0.00% | 0.00%
Assumed health-care cost trend rate |  |
Health-care cost escalation(1)(3) | 6.80% | 6.80%
Dental-care cost escalation | 4.00% | 4.00%
Other, through 2027 | Registered |  |
Disclosure of defined benefit plans [line items] |  |
Discount rate | 2.40% | 3.00%
Rate of compensation increase | 2.90% | 2.90%
Assumed health-care cost trend rate |  |
Health-care cost escalation(1)(3) | 0.00% | 0.00%
Dental-care cost escalation | 0.00% | 0.00%
Other, through 2027 | Supplemental Pension Plan |  |
Disclosure of defined benefit plans [line items] |  |
Discount rate | 2.30% | 3.00%
Rate of compensation increase | 3.00% | 3.00%
Assumed health-care cost trend rate |  |
Health-care cost escalation(1)(3) | 0.00% | 0.00%
Dental-care cost escalation | 0.00% | 0.00%
Other, through 2027 | Other, through 2027 |  |
Disclosure of defined benefit plans [line items] |  |
Discount rate | 2.30% | 3.00%
Rate of compensation increase | 0.00% | 0.00%
Assumed health-care cost trend rate |  |
Health-care cost escalation(1)(3) | 7.10% | 7.10%
Dental-care cost escalation | 4.00% | 4.00%

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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 2021-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_144&doctype=Standard -URIDate 2021-03-24 + 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 2021-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_144&doctype=Standard -URIDate 2021-03-24 + 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 2021-01-01 -Paragraph 144 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_144&doctype=Standard -URIDate 2021-03-24 + 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 2021-01-01 -Paragraph 145 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=19&code=ifrs-tx-2021-en-r&anchor=para_145_a&doctype=Standard -URIDate 2021-03-24 + Details
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