Trade and other payables (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Disclosure of detailed information about financial instruments [line items]
Trade payables	$ 64.1	$ 61.8
Interest payable	14.1	14.1
Accruals	73.1	65.2
Current portion of reclamation and closure cost obligations	0.8	1.7
Current portion of obligation	75.7	28.1
Current portion of derivative liabilities	1.1	0.0
Total trade and other payables	229.0	170.9
Gold Stream Obligation, Rainy River
Disclosure of detailed information about financial instruments [line items]
Current portion of obligation	33.1	28.1
New Afton free cash flow interest obligation
Disclosure of detailed information about financial instruments [line items]
Current portion of obligation	$ 42.7	$ 0.0

The amount of liabilities to pay for goods or services that have been received or supplied but have not been paid, invoiced or formally agreed with the supplier, including amounts due to employees.

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- Definition

The amount of current derivative financial liabilities. [Refer: Derivative financial liabilities]

+ References

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The amount of current interest payable. [Refer: Interest payable]

+ References

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

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- Definition

The amount of current financial liabilities that the entity does not separately disclose in the same statement or note. [Refer: Other financial liabilities; Current financial liabilities]

+ References

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

The amount of current provision for decommissioning, restoration and rehabilitation costs. [Refer: Provision for decommissioning, restoration and rehabilitation costs]

+ References

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- Definition

The amount of current trade payables and current other payables. [Refer: Current trade payables; Other current payables]

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- Definition

The amount of payment due to suppliers for goods and services used in the entity's business.

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