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

The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Revenues (Details) - CAD ($) $ in Millions	3 Months Ended								12 Months Ended
Revenues (Details) - CAD ($) $ in Millions	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									$ 7,254	$ 6,492	$ 6,173
Leasing revenues									62	62	59
Total revenues	$ 2,006	$ 1,898	$ 1,750	$ 1,662	$ 1,713	$ 1,595	$ 1,643	$ 1,603	7,316	6,554	6,232
Freight [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									7,152	6,375	6,060
Freight [Member] \| Grain revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									1,566	1,532	1,480
Freight [Member] \| Coal revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									673	631	606
Freight [Member] \| Potash revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									486	411	338
Freight [Member] \| Fertilizer and sulphur revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									243	241	284
Freight [Member] \| Forest products revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									284	265	275
Freight [Member] \| Energy, chemicals and plastics revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									1,243	898	852
Freight [Member] \| Metals, minerals and consumer products revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									797	739	564
Freight [Member] \| Automotive revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									322	293	350
Freight [Member] \| Intermodal revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									1,538	1,365	1,311
Non-freight [Member]
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers									$ 102	$ 117	$ 113