Subsequent events - Schedule of allocation of estimated provisional amounts acquired (Details) - Subsequent Event - KCS $ in Billions	Apr. 13, 2023 CAD ($)
Net assets acquired:
Cash and cash equivalents	$ 0.3
Net working capital	0.3
Properties	27.7
Intangible assets	2.6
Other long-term assets	0.4
Long-term debt	(4.5)
Deferred income taxes	(6.6)
Other long-term liabilities	(0.5)
Total identifiable net assets	19.7
Goodwill	18.5
Total identifiable net assets and goodwill	38.2
Consideration:
Fair value of previously held equity method investment	37.2
Estimated fair value of non-controlling interest	1.0
Total	38.2
Contracts and Customer Relationships
Net assets acquired:
Intangible assets	$ 2.6