Trade and other receivables - Disclosure of Trade Receivables Denominated in Other Currency Explanatory (Details) - CHF (SFr) SFr in Thousands	Dec. 31, 2025	Dec. 31, 2024
Disclosure Of Trade And Other Receivables [Line Items]
Trade receivables	SFr 253	SFr 286
EUR
Disclosure Of Trade And Other Receivables [Line Items]
Trade receivables	SFr 253	SFr 286

The amount of current trade receivables. [Refer: Trade receivables]

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Name:	ifrs-full_CurrentTradeReceivables
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant