Financial risk management - Credit risk (Details) - CREDIT RISK EXPOSURE - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
CREDIT RISK EXPOSURE
Maximum exposure to credit risk	$ 507.9	$ 263.4
Cash and cash equivalents
CREDIT RISK EXPOSURE
Maximum exposure to credit risk	481.5	186.3
Trade and other receivables
CREDIT RISK EXPOSURE
Maximum exposure to credit risk	$ 26.4	$ 77.1

The amount that best represents the maximum exposure to credit risk without taking into account any collateral held or other credit enhancements (for example, netting agreements that do not qualify for offset in accordance with IAS 32). [Refer: Credit risk [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2021-01-01
-Paragraph 35K
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-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2021-en-r&anchor=para_35K_a&doctype=Standard
-URIDate 2021-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2023-01-01
-Name IFRS
-Number 7
-IssueDate 2021-01-01
-Paragraph 36
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_36_a&doctype=Standard&book=b
-URIDate 2021-03-24

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