Description of Business and Nature of Operations - Additional Information (Detail)	12 Months Ended
Dec. 31, 2017
Cerro Casale Project [member]
Description of business and nature of operations [line items]
Percentage of interest acquired	50.00%
Exeter Resource Corporation [member]
Description of business and nature of operations [line items]
Percentage of interest acquired	100.00%
Leagold Mining Corporation [member]
Description of business and nature of operations [line items]
Percentage of ownership in associate	22.90%
Pueblo Viejo Dominicana Corporation [member]
Description of business and nature of operations [line items]
Percentage of ownership in associate	40.00%
NuevaUnion SpA [member]
Description of business and nature of operations [line items]
Percentage of ownership in associate	50.00%
Norte Abierto [member]
Description of business and nature of operations [line items]
Percentage of ownership in associate	50.00%
Norte Abierto [member] \| Barrick [member]
Description of business and nature of operations [line items]
Percentage of ownership in associate	50.00%

Description of business and nature of operations [line items]

No definition available.

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- Definition

The percentage of voting equity interests acquired in a business combination. [Refer: Business combinations [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2017-01-01
-Paragraph B64
-Subparagraph c
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-URIDate 2017-03-09

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2017-01-01
-Paragraph 17
-Subparagraph b
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=27&date=2017-03-01&anchor=para_17_b_iii&doctype=Standard
-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 27
-IssueDate 2017-01-01
-Paragraph 16
-Subparagraph b
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=27&date=2017-03-01&anchor=para_16_b_iii&doctype=Standard
-URIDate 2017-03-09

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2017-01-01
-Paragraph 21
-Subparagraph a
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=12&date=2017-03-01&anchor=para_21_a_iv&doctype=Standard
-URIDate 2017-03-09

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 12
-IssueDate 2017-01-01
-Paragraph 21
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-URIDate 2017-03-09

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- Details

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- Details

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- Details

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