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Business acquisition shares issued or issuable.

No definition available.

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Balance Type:	na
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Consideration paid.

No definition available.

Name:	groy_ConsiderationPaid
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Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration

Consulting fees.

No definition available.

Name:	groy_ConsultingFees
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Period Type:	duration

- References

No definition available.

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Period Type:	duration

Expected life.

No definition available.

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Balance Type:	na
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Estimated forfeiture rate.

No definition available.

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Balance Type:	na
Period Type:	duration

- References

No definition available.

Name:	groy_IfrsStatementLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Net profit interest royalty percentage.

No definition available.

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Balance Type:	na
Period Type:	instant

Net smelter return royalty percentage.

No definition available.

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Balance Type:	na
Period Type:	instant

Number of Options Issued.

No definition available.

Name:	groy_NumberOfOptionsIssued
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Number of royalties acquired.

No definition available.

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Namespace Prefix:	groy_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Number of shares issued on acquisition.

No definition available.

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Namespace Prefix:	groy_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Number of warrants issued to purchase shares.

No definition available.

Name:	groy_NumberOfWarrantsIssuedToPurchaseShares
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Balance Type:	na
Period Type:	duration

Payment from cash consideration.

No definition available.

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

Share price.

No definition available.

Name:	groy_SharePricePerShare
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Balance Type:	na
Period Type:	instant

Transaction costs.

No definition available.

Name:	groy_TransactionCosts
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Warrants deemed to be exchanged for Shares.

No definition available.

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

The fair value, at acquisition date, of the consideration transferred in a business combination. [Refer: Business combinations [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2021-01-01
-Paragraph B64
-Subparagraph f
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2021-en-r&anchor=para_B64_f&doctype=Appendix&subtype=B
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The fair value, at acquisition date, of cash transferred as consideration in a business combination. [Refer: Business combinations [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 3
-IssueDate 2021-01-01
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-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=3&code=ifrs-tx-2021-en-r&anchor=para_B64_f_i&doctype=Appendix&subtype=B
-URIDate 2021-03-24

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

The amount of consideration paid or received in respect of both obtaining and losing control of subsidiaries or other businesses. [Refer: Subsidiaries [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 7
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-URIDate 2021-03-24

Name:	ifrs-full_ConsiderationPaidReceived
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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-IssueDate 2021-01-01
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-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_47_a_i&doctype=Standard
-URIDate 2021-03-24

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The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for share options granted is expressed, with a remaining term equal to the expected term of the option being valued (based on the option's remaining contractual life and taking into account the effects of expected early exercise). [Refer: Government [member]]

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The exercise price of share options granted.

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Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
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Period Type:	duration

The percentage of an expected dividend used to calculate the fair value of share options granted.

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Balance Type:	na
Period Type:	duration

The amount of expense from share-based payment transactions with employees. [Refer: Expense from share-based payment transactions]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 112
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-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2021-03-24

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

The number of other equity instruments (ie other than share options) exercisable in a share-based payment arrangement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2021-01-01
-Paragraph 45
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45&doctype=Standard
-URIDate 2021-03-24

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Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

The number of share options outstanding in a share-based payment arrangement.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2021-01-01
-Paragraph 45
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_d&doctype=Standard
-URIDate 2021-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2021-01-01
-Paragraph 45
-Subparagraph b
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_b_i&doctype=Standard
-URIDate 2021-03-24

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2021-01-01
-Paragraph 45
-Subparagraph b
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-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_b_vi&doctype=Standard
-URIDate 2021-03-24

Name:	ifrs-full_NumberOfOutstandingShareOptions
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Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

The number of shares issued by the entity.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 106
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_106_d&doctype=Standard
-URIDate 2021-03-24

Name:	ifrs-full_NumberOfSharesIssued
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

The weighted average share price used as input to the option pricing model to calculate the fair value of share options granted. [Refer: Option pricing model [member]; Weighted average [member]]

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Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

Name:	ifrs-full_BusinessCombinationsAxis=groy_ElyMember
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Balance Type:
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Name:	ifrs-full_BusinessCombinationsAxis=groy_GoldenValleyAndAbitibiMember
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Data Type:	na
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Name:	ifrs-full_ClassesOfPropertyPlantAndEquipmentAxis=groy_CanadianMalarticPropertyMember
Namespace Prefix:
Data Type:	na
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Name:	ifrs-full_TypesOfContractsAxis=groy_RoyaltyOneMember
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Data Type:	na
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Name:	ifrs-full_TypesOfContractsAxis=groy_RoyaltyTwoMember
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Name:	ifrs-full_TypesOfContractsAxis=groy_RoyaltyThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	ifrs-full_ClassesOfPropertyPlantAndEquipmentAxis=groy_CheechooProjectMember
Namespace Prefix:
Data Type:	na
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Name:	ifrs-full_RangeAxis=ifrs-full_BottomOfRangeMember
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Data Type:	na
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Name:	ifrs-full_RangeAxis=ifrs-full_TopOfRangeMember
Namespace Prefix:
Data Type:	na
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Name:	ifrs-full_BusinessCombinationsAxis=groy_GoldenValleyMinesAndRoyaltiesLtdMember
Namespace Prefix:
Data Type:	na
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Name:	ifrs-full_BusinessCombinationsAxis=groy_AbitibiRoyaltiesIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	ifrs-full_ComponentsOfEquityAxis=groy_GRCSharesMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	ifrs-full_ComponentsOfEquityAxis=groy_ElyWarrantMember
Namespace Prefix:
Data Type:	na
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