Trade and other payables (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Disclosure of detailed information about financial instruments [line items]
Trade payables	$ 41.6	$ 39.7
Interest payable	16.7	6.1
Accruals	57.4	65.5
Current portion of reclamation and closure cost obligations (Note 15)	5.7	12.3
Current portion of gold stream obligation (Note 12)	36.6	21.6
Current portion of derivative liabilities (Note 14)	0.0	26.4
Total trade and other payables	158.0	171.6
Rainy River
Disclosure of detailed information about financial instruments [line items]
Current portion of gold stream obligation (Note 12)	32.1	21.6
New Afton
Disclosure of detailed information about financial instruments [line items]
Current portion of gold stream obligation (Note 12)	$ 4.5	$ 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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The amount of current derivative financial liabilities. [Refer: Derivative financial liabilities]

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

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

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No definition available.

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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]

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

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

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

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