Gain on Sale of Properties - Gain on Sale of Arbutus Corridor (Details) - Arbutus Corridor [Member] CAD in Millions	3 Months Ended
Mar. 31, 2016 CAD
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from sale	CAD 55
Gain on sale before tax	50
Gain on sale after tax	CAD 43

Gain (Loss) on Disposition of Property Plant Equipment, after Tax

No definition available.

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Namespace Prefix:	cp_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- 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.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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