Amount of fund to be distributed to those claiming derailment damages.

No definition available.

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

- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14557-108349

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Number of plaintiffs that have filed claims pertaining to a loss contingency.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of pending claims pertaining to a loss contingency.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

+ Details

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Balance Type:	na
Period Type:	instant

- 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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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Contingencies - Legal Proceedings (Details) - Lac-Megantic Rail Accident [Member] $ in Millions									3 Months Ended
	May 14, 2018 CAD ($) claim	Dec. 28, 2017 CAD ($)	Oct. 10, 2017 CAD ($)	Jul. 11, 2016 CAD ($) claim	Jul. 05, 2016 CAD ($)	Jul. 04, 2016 CAD ($) claim	Apr. 12, 2016 CAD ($)	Jul. 06, 2015 CAD ($)	Mar. 31, 2019 CAD ($)
Claimed damages as a result of derailment
Other Commitments [Line Items]
Amount of fund to be distributed									$ 440
Irving Oil [Member]
Other Commitments [Line Items]
Value of damages sought							$ 60
Quebec Minister of Sustainable Development, Environment, Wildlife and Parks
Other Commitments [Line Items]
Value of damages sought					$ 95
Quebec Attorney General
Other Commitments [Line Items]
Value of damages sought			$ 315					$ 409
Initial Insurer Claimants \| Subrogated insurance claim
Other Commitments [Line Items]
Value of damages sought		$ 14				$ 16
Number of pending claims \| claim						8
Additional Insurer Claimants \| Subrogated insurance claim
Other Commitments [Line Items]
Value of damages sought				$ 3
Number of pending claims \| claim				2
Plaintiff [Member]
Other Commitments [Line Items]
Value of damages sought	$ 5
Number of Plaintiffs \| claim	48
The WD Trustee \| Damaged rail cars loss recovery
Other Commitments [Line Items]
Value of damages sought							6
Montreal Maine and Atlantic Railway
Other Commitments [Line Items]
Value of damages sought							$ 110