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Employee Future Benefits (Tables) | 12 Months Ended
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Dec. 31, 2023
Employee Benefits [Abstract] |
Disclosure of costs recognized | The costs recognized in net earnings during the year on the defined benefit, defined contribution and other post-employment benefits plans are as follows:
Year ended Dec. 31, 2023 | Registered | Supplemental | Other | Total
Current service cost | 1 |  | 1 |  | — |  | 2 |
Administration expenses | 1 |  | — |  | — |  | 1 |
Interest cost on defined benefit obligation | 16 |  | 4 |  | 1 |  | 21 |
Interest on plan assets | (13) |  | (1) |  | — |  | (14) |
Defined benefit expense | 5 |  | 4 |  | 1 |  | 10 |
Defined contribution expense | 11 |  | — |  | — |  | 11 |
Net expense | 16 |  | 4 |  | 1 |  | 21 |
Year ended Dec. 31, 2022 | Registered | Supplemental | Other | Total
Current service cost | 1 |  | 1 |  | — |  | 2 |
Administration expenses | 1 |  | — |  | — |  | 1 |
Interest cost on defined benefit obligation | 13 |  | 3 |  | — |  | 16 |
Interest on plan assets | (9) |  | — |  | — |  | (9) |
Defined benefit expense | 6 |  | 4 |  | — |  | 10 |
Defined contribution expense | 11 |  | — |  | — |  | 11 |
Net expense | 17 |  | 4 |  | — |  | 21 |
Year ended Dec. 31, 2021 | Registered | Supplemental | Other | Total
Current service cost | 3 |  | 2 |  | 1 |  | 6 |
Administration expenses | 1 |  | — |  | — |  | 1 |
Interest cost on defined benefit obligation | 12 |  | 2 |  | — |  | 14 |
Interest on plan assets | (8) |  | — |  | — |  | (8) |
Curtailment and amendment gain | (7) |  | — |  | — |  | (7) |
Defined benefit expense | 1 |  | 4 |  | 1 |  | 6 |
Defined contribution expense | 8 |  | — |  | — |  | 8 |
Net expense | 9 |  | 4 |  | 1 |  | 14 |
The expected employer contributions for 2024 for the defined benefit pension and other post-employment benefit plans are as follows:
| Registered | Supplemental | Other | Total
Expected employer contributions | 3 |  | 5 |  | 1 |  | 9 |
Disclosure of defined benefit obligation | The status of the defined benefit pension and other post-employment benefit plans is as follows:
Year ended Dec. 31, 2023 | Registered | Supplemental | Other | Total
Fair value of plan assets | 269 |  | 15 |  | — |  | 284 |
Present value of defined benefit obligation | (340) |  | (89) |  | (17) |  | (446) |
Funded status – plan deficit | (71) |  | (74) |  | (17) |  | (162) |
Amount recognized in the Consolidated Financial Statements: |  |  |  |
Accrued current liabilities | (1) |  | (5) |  | (1) |  | (7) |
Other long-term liabilities | (70) |  | (69) |  | (16) |  | (155) |
Total amount recognized | (71) |  | (74) |  | (17) |  | (162) |
Year ended Dec. 31, 2022 | Registered | Supplemental | Other | Total
Fair value of plan assets | 274 |  | 15 |  | — |  | 289 |
Present value of defined benefit obligation | (345) |  | (85) |  | (17) |  | (447) |
Funded status – plan deficit | (71) |  | (70) |  | (17) |  | (158) |
Amount recognized in the Consolidated Financial Statements: |  |  |  |
Accrued current liabilities | (1) |  | (6) |  | (1) |  | (8) |
Other long-term liabilities | (70) |  | (64) |  | (16) |  | (150) |
Total amount recognized | (71) |  | (70) |  | (17) |  | (158) |
The present value of the obligation for the defined benefit pension and other post-employment benefit plans is as follows:
| Registered | Supplemental | Other | Total
Present value of defined benefit obligation as at Dec. 31, 2021 | 469 |  | 101 |  | 23 |  | 593 |
Current service cost | 1 |  | 1 |  | — |  | 2 |
Interest cost | 13 |  | 3 |  | — |  | 16 |
Benefits paid | (57) |  | (5) |  | 1 |  | (61) |
Actuarial gain arising from financial assumptions | (83) |  | (22) |  | (5) |  | (110) |
Actuarial gain arising from experience adjustments | 1 |  | 7 |  | (2) |  | 6 |
Change in foreign exchange rates | 1 |  | — |  | — |  | 1 |
Present value of defined benefit obligation as at Dec. 31, 2022 | 345 |  | 85 |  | 17 |  | 447 |
Current service cost | 1 |  | 1 |  | — |  | 2 |
Interest cost | 16 |  | 4 |  | 1 |  | 21 |
Benefits paid | (36) |  | (6) |  | (2) |  | (44) |
Actuarial loss arising from demographic assumptions | 1 |  | — |  | — |  | 1 |
Actuarial loss arising from financial assumptions | 12 |  | 4 |  | 1 |  | 17 |
Actuarial loss arising from experience adjustments | 2 |  | 1 |  | — |  | 3 |
Change in foreign exchange rates | (1) |  | — |  | — |  | (1) |
Present value of defined benefit obligation as at Dec. 31, 2023 | 340 |  | 89 |  | 17 |  | 446 |
(1)The weighted average duration of the defined benefit plan obligation as at Dec. 31, 2023, is 10.4 years.
Disclosure of plan assets | The fair value of the plan assets of the defined benefit pension and other post-employment benefit plans is as follows:
| Registered | Supplemental | Other | Total
As at Dec. 31, 2021 | 339 |  | 14 |  | — |  | 353 |
Interest on plan assets | 9 |  | — |  | — |  | 9 |
Net loss on plan assets | (55) |  | — |  | — |  | (55) |
Contributions(1) | 38 |  | 6 |  | — |  | 44 |
Benefits paid | (57) |  | (5) |  | — |  | (62) |
Administration expenses | (1) |  | — |  | — |  | (1) |
Change in foreign exchange rates | 1 |  | — |  | — |  | 1 |
As at Dec. 31, 2022 | 274 |  | 15 |  | — |  | 289 |
Interest on plan assets | 13 |  | 1 |  | — |  | 14 |
Net return on plan assets | 15 |  | (1) |  | — |  | 14 |
Contributions(2) | 5 |  | 6 |  | 2 |  | 13 |
Benefits paid | (36) |  | (6) |  | (2) |  | (44) |
Administration expenses | (1) |  | — |  | — |  | (1) |
Change in foreign exchange rates | (1) |  | — |  | — |  | (1) |
As at Dec. 31, 2023 | 269 |  | 15 |  | — |  | 284 |
(1)The Company made a voluntary contribution of $35 million to further improve the funded status of the Sunhills Mining Ltd. Pension Plan for the Highvale mine. The contribution reduces the amount of the Company's future funding obligations, including amounts secured by the letters of credit. (2)The Company made a voluntary contribution of $4 million to further improve the funded status of the US Defined Benefit Pension Plan for the Centralia thermal facility. The fair value of the Company’s defined benefit plan assets by major category is as follows:
As at Dec. 31, 2023 | Level I | Level II | Level III | Total
Equity securities |  |  |  |
Canadian | — |  | 12 |  | — |  | 12 |
US | — |  | 6 |  | — |  | 6 |
International | — |  | 86 |  | — |  | 86 |
Private | — |  | — |  | 1 |  | 1 |
Bonds |  |  |  |
A - AAA | — |  | 30 |  | 62 |  | 92 |
BBB | 1 |  | 5 |  | 10 |  | 16 |
Below BBB | — |  | — |  | 4 |  | 4 |
Loans(1) | — |  | 2 |  | — |  | 2 |
Alternative funds(2) | — |  | — |  | 44 |  | 44 |
Money market and cash and cash equivalents | 2 |  | 19 |  | — |  | 21 |
Total | 3 |  | 160 |  | 121 |  | 284 |
(1)Includes A credit rating loans of $1 million. (2)Alternative funds include investments in infrastructure and real estate funds.
Dec. 31, 2022(1) | Level I | Level II | Level III | Total
Equity securities |  |  |  |
Canadian | — |  | 18 |  | — |  | 18 |
US | — |  | 17 |  | — |  | 17 |
International | — |  | 79 |  | — |  | 79 |
Private | — |  | — |  | 1 |  | 1 |
Bonds |  |  |  |
A - AAA | — |  | 27 |  | 61 |  | 88 |
BBB | 1 |  | 6 |  | 12 |  | 19 |
Below BBB | — |  | — |  | 6 |  | 6 |
Loans(2) | — |  | 2 |  | — |  | 2 |
Alternative funds(3) | — |  | — |  | 39 |  | 39 |
Money market and cash and cash equivalents | — |  | 20 |  | — |  | 20 |
Total | 1 |  | 169 |  | 119 |  | 289 |
(1)The fair value level classifications of certain mutual fund investments has been revised for consistency with 2023 classifications. (2)Includes A credit rating loans of $1 million and BBB credit rating loans of $1 million. (3)Alternative funds include investments in infrastructure and real estate funds.
Disclosure of assumptions | Assumptions The significant actuarial assumptions used in measuring the Company’s defined benefit obligation for the defined benefit pension and other post-employment benefit plans are as follows:
| 2023 |  | 2022
As at Dec. 31 (per cent) | Registered | Supplemental | Other |  | Registered | Supplemental | Other
Accrued benefit obligation |  |  |  |  |  |  |
Discount rate | 4.6 |  | 4.6 |  | 4.7 |  |  | 4.7 |  | 5.0 |  | 5.0 |
Rate of compensation increase | 2.9 |  | 3.0 |  | — |  |  | 2.6 |  | 3.0 |  | — |
Assumed health-care cost trend rate |  |  |  |  |  |  |
Health-care cost escalation(1)(3) | — |  | — |  | 6.8 |  |  | — |  | — |  | 7.1 |
Dental-care cost escalation | — |  | — |  | 4.2 |  |  | — |  | — |  | 4.2 |
Benefit cost for the year |  |  |  |  |  |  |
Discount rate | 5.0 |  | 5.0 |  | 5.0 |  |  | 2.8 |  | 2.8 |  | 2.7 |
Rate of compensation increase | 2.7 |  | 3.0 |  | — |  |  | 2.9 |  | 3.0 |  | — |
Assumed health-care cost trend rate |  |  |  |  |  |  |
Health-care cost escalation(2)(4) | — |  | — |  | 7.1 |  |  | — |  | — |  | 6.8 |
Dental-care cost escalation | — |  | — |  | 4.7 |  |  | — |  | — |  | 4.7 |
(1)2023 Post- and pre-65 rates: decreasing gradually to 4.5 per cent by 2033 and remaining at that level thereafter for the US and decreasing gradually by 0.3 per cent per year to 4.5 per cent in 2030 for Canada. (2)2023 Post- and pre-65 rates: decreasing gradually to 4.5 per cent by 2032 and remaining at that level thereafter for the US and decreasing gradually by 0.3 per cent per year to 4.5 per cent in 2030 for Canada. (3)2022 Post- and pre-65 rates: decreasing gradually to 4.5 per cent by 2032 and remaining at that level thereafter for the US and decreasing gradually by 0.3 per cent per year to 4.5 per cent in 2030 for Canada. (4)2022 Post- and pre-65 rates: decreasing gradually to 4.5 per cent by 2031 and remaining at that level thereafter for the US and decreasing gradually by 0.3 per cent per year to 4.5 per cent in 2030 for Canada.
Disclosure of estimated increase in the net defined benefit obligation assuming certain changes in key assumptions | The following table outlines the estimated increase in the net defined benefit obligation assuming certain changes in key assumptions:
| Canadian plans |  | US plans
As at Dec. 31, 2023 | Registered | Supplemental | Other |  | Pension |
1% decrease in the discount rate | 30 |  | 10 |  | 1 |  |  | 2 |  |
1% increase in the salary scale | 1 |  | — |  | — |  |  | — |  |
1% increase in the health-care cost trend rate | — |  | — |  | 1 |  |  | — |  |
10% improvement in mortality rates | 13 |  | 3 |  | — |  |  | 1 |  |

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