Accounts Receivable, Net (Details) - CAD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, Gross	$ 845	$ 712
Allowance for doubtful accounts	(30)	(25)
Accounts receivable, net	815	687
Freight [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, Gross	677	536
Non-freight [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, Gross	$ 168	$ 176

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business.

+ References

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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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