XML 202 R175.htm IDEA: XBRL DOCUMENT v3.24.0.1
Pension Plans and Other Post-Retirement Benefits - Schedule of Actuarial Assumptions (Details) - year
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Canada    
To determine defined benefit obligation at end of year:    
Discount rate for pension plans 4.60% 5.00%
Rate of compensation increase 2.70% 2.75%
To determine net benefit expense for year:    
Discount rate for pension plans 5.00% 3.00%
Rate of compensation increase 2.75% 2.80%
Health care trend rates:    
Initial health care trend rate 5.08% 5.16%
Ultimate health care trend rate 4.00% 4.00%
Year ultimate health care trend rate reached 2040 2040
Mortality rates:    
Average duration (in years) of pension obligation 13 years 9 months 18 days 13 years 2 months 12 days
United Kingdom    
To determine defined benefit obligation at end of year:    
Discount rate for pension plans   4.75%
Pension increases   3.05%
To determine net benefit expense for year:    
Discount rate for pension plans 4.75% 1.90%
Pension increases 3.05% 3.30%
Mortality rates:    
Average duration (in years) of pension obligation   12 years 10 months 24 days
U.S.    
To determine defined benefit obligation at end of year:    
Discount rate for pension plans 5.35% 5.55%
To determine net benefit expense for year:    
Discount rate for pension plans 5.55% 3.00%
Health care trend rates:    
Initial health care trend rate 6.75% 7.00%
Ultimate health care trend rate 5.00% 5.00%
Year ultimate health care trend rate reached 2031 2031
Mortality rates:    
Average duration (in years) of pension obligation 9 years 9 months 18 days 10 years
Bottom of range | Canada    
To determine defined benefit obligation at end of year:    
Pension increases 0.00% 0.00%
To determine net benefit expense for year:    
Pension increases 0.00% 0.00%
Top of range | Canada    
To determine defined benefit obligation at end of year:    
Pension increases 0.20% 0.05%
To determine net benefit expense for year:    
Pension increases 0.05% 0.05%
Male - Individuals currently at age 65 | Canada    
Mortality rates:    
Life expectancy (in years) for individuals 24 23
Male - Individuals currently at age 65 | United Kingdom    
Mortality rates:    
Life expectancy (in years) for individuals   23
Male - Individuals currently at age 65 | U.S.    
Mortality rates:    
Life expectancy (in years) for individuals 22 22
Female - Individuals currently at age 65 | Canada    
Mortality rates:    
Life expectancy (in years) for individuals 25 25
Female - Individuals currently at age 65 | United Kingdom    
Mortality rates:    
Life expectancy (in years) for individuals   25
Female - Individuals currently at age 65 | U.S.    
Mortality rates:    
Life expectancy (in years) for individuals 23 23
Male - At 65 for individuals currently at age 45 | Canada    
Mortality rates:    
Life expectancy (in years) for individuals 25 24
Male - At 65 for individuals currently at age 45 | United Kingdom    
Mortality rates:    
Life expectancy (in years) for individuals   25
Male - At 65 for individuals currently at age 45 | U.S.    
Mortality rates:    
Life expectancy (in years) for individuals 23 23
Female - At 65 for individuals currently at age 45 | Canada    
Mortality rates:    
Life expectancy (in years) for individuals 26 26
Female - At 65 for individuals currently at age 45 | United Kingdom    
Mortality rates:    
Life expectancy (in years) for individuals   27
Female - At 65 for individuals currently at age 45 | U.S.    
Mortality rates:    
Life expectancy (in years) for individuals 25 25