Business Combination, Consideration Transferred, Entity Shares Issued per Acquiree Share

No definition available.

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Balance Type:	na
Period Type:	instant

- Definition

Business Combination, Consideration Transferred, Entity Shares Issued per Acquiree Share, Post Share Split

+ References

No definition available.

+ Details

Name:	cp_BusinessCombinationConsiderationTransferredEntitySharesIssuedPerAcquireeSharePostShareSplit
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Balance Type:	na
Period Type:	instant

- Definition

Business Combination Transaction Value

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Termination Fee, Early Contract Termination, Change in Board Recommendation

+ References

No definition available.

+ Details

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- Definition

Termination Fee, Early Contract Termination, Required Regulatory Approval

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

+ Details

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Data Type:	num:perShareItemType
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Period Type:	instant

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e1043-128460

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of liabilities assumed at the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121647850&loc=d3e4845-128472

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow for financing costs associated with business combinations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

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- Details

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- Details

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Business Acquisition (Details) $ / shares in Units, $ in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2021 CAD ($)	Mar. 31, 2020 CAD ($)	Mar. 21, 2021 $ / shares	Mar. 21, 2021 USD ($) shares
Business Acquisition [Line Items]
Acquisition-related costs	$ 36
Acquisition-related costs, Financing fees	33	$ 0
KCS [Member]
Business Acquisition [Line Items]
Exchange ratio of CP common share to KCS common share \| shares				0.489
Exchange ratio of CP common share to KCS common share, Post share split \| shares				2.445
KCS transaction enterprise value				$ 29,000
Outstanding KCS debt				3,800
Acquisition-related costs	36
Acquisition-related costs, Financing fees	33
Termination Fee, Change in Board Recommendation				700
Termination Fee, Required Regulatory Approval				$ 1,000
KCS [Member] \| Purchased services and other
Business Acquisition [Line Items]
Acquisition-related costs	33
KCS [Member] \| Other (Income) Expense
Business Acquisition [Line Items]
Acquisition-related costs	$ 3
KCS [Member] \| Common stock
Business Acquisition [Line Items]
Cash for KCS share held \| $ / shares			$ 90
KCS [Member] \| Preferred Stock
Business Acquisition [Line Items]
Cash for KCS share held \| $ / shares			$ 37.50