financial instruments - Fair values Non-derivative (Details) - CAD ($) $ in Millions |
Jun. 30, 2019 |
Dec. 31, 2018 |
|---|---|---|
| Disclosure of detailed information about financial instruments | ||
| Long term Borrowings Current And Non current Excluding Lease Liabilities | $ 15,025 | $ 13,999 |
| Measured at amortized cost but fair value disclosed | ||
| Disclosure of detailed information about financial instruments | ||
| Long term Borrowings Current And Non current Excluding Lease Liabilities | 16,105 | 14,107 |
| Carrying value | ||
| Disclosure of detailed information about financial instruments | ||
| Long term Borrowings Current And Non current Excluding Lease Liabilities | $ 15,025 | $ 13,999 |