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Employee Future Benefits - Sensitivity Analysis (Details) $ in Millions | Dec. 31, 2021 CAD ($)
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1% decrease in the discount rate |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Percentage of reasonably possible increase in actuarial assumption (as percent) | 1.00%
Percentage of reasonably possible increase in actuarial assumption (as percent) | 1.00%
1% increase in the salary scale |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Percentage of reasonably possible increase in actuarial assumption (as percent) | 1.00%
Percentage of reasonably possible increase in actuarial assumption (as percent) | 1.00%
1% increase in the health-care cost trend rate |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Percentage of reasonably possible increase in actuarial assumption (as percent) | 1.00%
Percentage of reasonably possible increase in actuarial assumption (as percent) | 1.00%
10% improvement in mortality rates |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Percentage of reasonably possible increase in actuarial assumption (as percent) | 10.00%
Percentage of reasonably possible increase in actuarial assumption (as percent) | 10.00%
Registered Pension Plan | Canada | 1% decrease in the discount rate |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | $ 61
Registered Pension Plan | Canada | 1% increase in the salary scale |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 3
Registered Pension Plan | Canada | 1% increase in the health-care cost trend rate |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 0
Registered Pension Plan | Canada | 10% improvement in mortality rates |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 20
Registered Pension Plan | US | 1% decrease in the discount rate |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 3
Registered Pension Plan | US | 1% increase in the salary scale |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 0
Registered Pension Plan | US | 1% increase in the health-care cost trend rate |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 0
Registered Pension Plan | US | 10% improvement in mortality rates |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 1
Supplemental Pension Plan | Canada | 1% decrease in the discount rate |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 15
Supplemental Pension Plan | Canada | 1% increase in the salary scale |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 0
Supplemental Pension Plan | Canada | 1% increase in the health-care cost trend rate |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 0
Supplemental Pension Plan | Canada | 10% improvement in mortality rates |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 4
Other | Canada | 1% decrease in the discount rate |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 2
Other | Canada | 1% increase in the salary scale |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 0
Other | Canada | 1% increase in the health-care cost trend rate |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 2
Other | Canada | 10% improvement in mortality rates |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 0
Other | US | 1% decrease in the discount rate |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 1
Other | US | 1% increase in the salary scale |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 0
Other | US | 1% increase in the health-care cost trend rate |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | 0
Other | US | 10% improvement in mortality rates |
Disclosure of sensitivity analysis for actuarial assumptions [line items] |
Increase in defined benefit obligation | $ 0

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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 increase (decrease) in a defined benefit obligation that would have been caused by an increase in a significant actuarial assumption that was reasonably possible at the end of the reporting period. [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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