Properties - Capital Leases Included in Properties (Details) - CAD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Capital Leased Assets [Line Items]
Cost	$ 307	$ 312
Accumulated depreciation	130	125
Net book value	177	187
Buildings
Capital Leased Assets [Line Items]
Cost	0	1
Accumulated depreciation	0	1
Net book value	0	0
Rolling stock
Capital Leased Assets [Line Items]
Cost	303	311
Accumulated depreciation	130	124
Net book value	173	$ 187
Other
Capital Leased Assets [Line Items]
Cost	4
Accumulated depreciation	0
Net book value	$ 4

Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=84164758&loc=d3e45014-112735

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- Definition

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.

+ References

No definition available.

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- Definition

The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737

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- Definition

The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 55
-Paragraph 40
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-Name Accounting Standards Codification
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