Leases - Maturities of Lease Liabilities (Details) $ in Millions	Dec. 31, 2023 CAD ($)
Finance leases
2024	$ 15
2025	14
2026	14
2027	1
2028	0
Thereafter	7
Total lease future payments	51
Imputed interest	(6)
Present value of future lease payments	45
Operating leases
2024	110
2025	86
2026	77
2027	50
2028	30
Thereafter	29
Total lease future payments	382
Imputed interest	(37)
Present value of future lease payments	$ 345