Summary of Significant Accounting Policies - Summary of Investments in Associates and Joint Arrangements (Detail)	12 Months Ended
Dec. 31, 2017
Pueblo Viejo Dominicana Corporation [member]
Disclosure of Joint Ventures and Associates [Line Items]
Ownership interest	40.00%
Minera Alumbrera Limited [member]
Disclosure of Joint Ventures and Associates [Line Items]
Ownership interest	37.50%
Leagold Mining Corporation [member]
Disclosure of Joint Ventures and Associates [Line Items]
Ownership interest	22.90%
NuevaUnion SpA [member]
Disclosure of Joint Ventures and Associates [Line Items]
Ownership interest	50.00%
Nueva Union [member] \| NuevaUnion SpA [member] \| Operating segments [member]
Disclosure of Joint Ventures and Associates [Line Items]
Mine sites and/or operating segments)	NuevaUnión SpA (“NuevaUnión”)
Location	Chile
Ownership interest	50.00%
Classification	Joint Venture; equity method
Mining properties	NuevaUnión project
Pueblo Viejo [member] \| Pueblo Viejo Dominicana Corporation [member] \| Operating segments [member]
Disclosure of Joint Ventures and Associates [Line Items]
Mine sites and/or operating segments) (notes 7, 9 and 20)	Pueblo Viejo Dominicana Corporation ("Pueblo Viejo")
Location	Dominican Republic
Ownership interest	40.00%
Classification	Associate
Mining properties	Pueblo Viejo mine
Alumbrera [member] \| Minera Alumbrera Limited [member] \| Operating segments [member]
Disclosure of Joint Ventures and Associates [Line Items]
Mine sites and/or operating segments) (notes 7, 9 and 20)	Minera Alumbrera Limited ("Alumbrera")
Location	Argentina
Ownership interest	37.50%
Classification	Associate
Mining properties	Alumbrera mine
Leagold [member] \| Leagold Mining Corporation [member] \| Operating segments [member]
Disclosure of Joint Ventures and Associates [Line Items]
Mine sites and/or operating segments) (notes 7, 9 and 20)	Leagold Mining Corporation ("Leagold")
Location	Mexico
Ownership interest	22.90%
Classification	Associate
Mining properties	Los Filos mine
Norte Abierto [member] \| Operating segments [member] \| Compania Minera Casale Spa [member]
Disclosure of Joint Ventures and Associates [Line Items]
Name of joint operation	Compañia Minera Casale SpA ("Norte Abierto")")
Location	Chile
Ownership interest	50.00%
Classification	Joint Operation; consolidate Goldcorp's share
Mining properties	Norte Abierto project

Disclosure of joint ventures and associates.

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Mining properties owned in associate.

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The name of an associate. [Refer: Associates [member]]

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The name of the entity's ultimate or any intermediate parent whose consolidated financial statements that comply with IFRSs have been produced for public use. [Refer: Consolidated [member]; IFRSs [member]]

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The name of a joint operation. [Refer: Joint operations [member]]

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The name of a joint venture. [Refer: Joint ventures [member]]

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- Definition

The principal place of business of an associate. [Refer: Principal place of business; Associates [member]]

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The principal place of business of a joint operation. [Refer: Joint operations [member]; Principal place of business]

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The principal place of business of a joint venture. [Refer: Principal place of business; Joint ventures [member]]

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The proportion of ownership interest in an associate attributable to the entity. [Refer: Associates [member]]

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The proportion of ownership interest in a joint operation attributable to the entity. [Refer: Joint operations [member]]

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