Acquisition (Narrative) (Details) $ in Millions, $ in Millions |
12 Months Ended | ||||||||
|---|---|---|---|---|---|---|---|---|---|
|
Sep. 15, 2021
CAD ($)
|
Sep. 15, 2021
USD ($)
|
May 21, 2021
CAD ($)
|
May 21, 2021
USD ($)
|
Dec. 31, 2022
CAD ($)
|
Dec. 31, 2021
CAD ($)
|
Dec. 31, 2020
CAD ($)
|
Sep. 30, 2021
CAD ($)
|
Jun. 30, 2021
CAD ($)
|
|
| Business Acquisition [Line Items] | |||||||||
| Merger termination fee | $ 0 | $ 886 | $ 0 | ||||||
| Refund of advance for acquisition | $ 0 | 886 | $ 0 | ||||||
| Bridge financing and other fees | 97 | ||||||||
| Kansas City Southern [Member] | |||||||||
| Business Acquisition [Line Items] | |||||||||
| Merger termination fee | $ 886 | $ 700 | |||||||
| Refund of advance for acquisition | $ 886 | $ 700 | |||||||
| Advance paid | $ 845 | $ 700 | |||||||
| Transaction costs | 84 | $ 63 | |||||||
| Transaction-related costs, gross | 125 | $ 49 | |||||||
| Transaction costs, previously capitalized | $ 76 | ||||||||
| Foreign exchange gain | 41 | ||||||||
| Additional income, pre-tax | 705 | ||||||||
| Additional income, after-tax | $ 616 | ||||||||