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Employee Future Benefits - Schedule of Assumptions Used (Details) | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023
DBP Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Discount rate as at December 31 | 5.25% | 4.84%
Expected long-term rate of return on plan assets | 6.51% | 6.58%
Rate of compensation increase | 3.52% | 3.37%
Health care cost trend increase as at December 31 | 0.00% | 0.00%
Discount rate during the year | 4.84% | 5.36%
OPEB Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Discount rate as at December 31 | 5.43% | 4.94%
Expected long-term rate of return on plan assets | 6.05% | 5.92%
Rate of compensation increase | 0.00% | 0.00%
Health care cost trend increase as at December 31 | 4.53% | 4.52%
Discount rate during the year | 4.96% | 5.39%
Health care cost trend rate assumed for next fiscal year | 6.51% |
Remaining period until health care cost trend rate reaches ultimate trend rate | 10 years |

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- Definition Defined Benefit Plan, Remaining Period Until Health Care Cost Trend Rate Reaches Ultimate Trend Rate + References No definition available. + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-8 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (l) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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