Foreign currency risk - Financial assets and liabilities held in foreign currency (Details) € in Millions, SFr in Millions, $ in Millions	Dec. 31, 2022 CHF (SFr)	Dec. 31, 2022 USD ($)	Dec. 31, 2022 EUR (€)	Dec. 31, 2021 CHF (SFr)	Dec. 31, 2021 USD ($)	Dec. 31, 2021 EUR (€)
Disclosure of financial assets [line items]
Cash and cash equivalents	SFr 371.0	$ 184.6	€ 9.2	SFr 653.1	$ 710.0	€ 2.1
Trade receivables and other financial assets		257.9	5.3		56.6	12.3
Trade payables and other financial liabilities		(42.9)	(0.7)		(5.2)	(9.6)
Total assets and liabilities		$ 399.6	€ 13.8		$ 761.3	€ 4.7

The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-IssueDate 2022-03-24
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-URIDate 2022-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Number 12
-IssueDate 2022-03-24
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-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=12&code=ifrs-tx-2022-en-r&anchor=para_B13_a&doctype=Appendix&subtype=B
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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Balance Type:	debit
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