Accounts Receivable (Details) - CAD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Accounts receivable
Gross accounts receivable	$ 1,386	$ 1,102
Allowance for credit losses	(15)	(28)
Net accounts receivable	1,371	1,074
Freight [Member]
Accounts receivable
Gross accounts receivable	1,142	877
Non-freight [Member]
Accounts receivable
Gross accounts receivable	$ 244	$ 225

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
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Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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