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Commitments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Commitments [Line Items]
Capital purchases commitments	$ 155.4	$ 123.8
Royalties	9.1	11.7
Outstanding commitments made by entity, related party transactions	115.1	89.4
Royal Gold [Member]
Commitments [Line Items]
Extraordinary mining duty tax	1.2	1.1
Island Gold
Commitments [Line Items]
Royalties	2.6	5.3
Net Smelter Royalty [Member] | AuRico Metals [Member]
Commitments [Line Items]
Royalties	$ 5.3	$ 5.3
Royalty rate	1.50%
Net Smelter Royalty [Member] | Island Gold
Commitments [Line Items]
Royalty rate	2.20%

X

- Definition

[Line Items] for Commitments [Table]

+ References

No definition available.

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- Definition

Extraordinary Mining Duty Tax

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- Definition

Royalty Rate

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X

- Definition

The amount of capital commitments for which the entity has entered into a contract. [Refer: Capital commitments]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The amount of outstanding commitments made by the entity in related party transactions. [Refer: Related parties [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of expense arising from royalties.

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