Grants, amount receivable.

No definition available.

Name:	aciu_GrantsAmountReceivable
Namespace Prefix:	aciu_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of current accrued income including current contract assets. [Refer: Accrued income including contract assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

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

- Definition

The amount of current deferred income other than current contract liabilities. [Refer: Deferred income other than contract liabilities]

+ References

+ Details

Name:	ifrs-full_CurrentDeferredIncomeOtherThanCurrentContractLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of liabilities representing income that has been received (or the amount is due) but is not yet earned, other than contract liabilities. [Refer: Contract liabilities]

+ References

+ Details

Name:	ifrs-full_DeferredIncomeOtherThanContractLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of current other receivables. [Refer: Other receivables]

+ References

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+ Details

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

- References

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+ Details

Name:	ifrs-full_OtherOperatingIncomeExpense
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

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+ Details

Name:	ifrs-full_RevenueFromContractsWithCustomers
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	ifrs-full_TypesOfContractsAxis=aciu_GrantFromVijayAndMarieGoradiaCharitableFoundationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Contract revenues and other operating income - Grant income (Details) SFr in Thousands, $ in Millions	6 Months Ended
	Jun. 30, 2026 CHF (SFr)	Jun. 30, 2025 CHF (SFr)	Jun. 11, 2026 USD ($)	Jun. 11, 2026 CHF (SFr)	Dec. 31, 2025 CHF (SFr)
Contract revenues
Income from grants	SFr 107	SFr 21
Revenue from contracts with customers	16,232	SFr 2,296
Accrued income	209				SFr 360
Other current receivables	3,514				SFr 978
Current deferred income	1,292
Grant from Vijay and Marie Goradia Charitable Foundation
Contract revenues
Grants, amount receivable			$ 4	SFr 3,200
Deferred income	3,100		4	3,200
Income from grants	100
Other current receivables			$ 4	SFr 3,200
Current deferred income	SFr 1,300