No definition available.

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- Definition

The number of other equity instruments (ie other than share options) exercised in a share-based payment arrangement.

+ References

No definition available.

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- References

No definition available.

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- References

No definition available.

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- Definition

Weighted average grant date fair value, other equity instruments exercised

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Weighted average grant date fair value, other equity instruments expired

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Weighted average grant date fair value, other equity instruments forfeited

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Weighted average grant date fair value, other equity instruments granted

+ References

No definition available.

+ Details

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Namespace Prefix:	aciu_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Weighted average grant date fair value, other equity instruments outstanding

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Weighted average grant date fair value, other equity instruments vested

+ References

No definition available.

+ Details

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Namespace Prefix:	aciu_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Weighted average grant date fair value, other equity instruments vested and exercisable

+ References

No definition available.

+ Details

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Namespace Prefix:	aciu_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of expense from share-based payment transactions with employees. [Refer: Expense from share-based payment transactions]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2024-01-01
-Paragraph 112
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2024-03-27

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of other equity instruments (ie other than share options) granted in a share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2024-01-01
-Paragraph 45
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2024-en-r&anchor=para_45&doctype=Standard
-URIDate 2024-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2024-01-01
-Paragraph 47
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2024-en-r&anchor=para_47_b&doctype=Standard
-URIDate 2024-03-27

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Data Type:	xbrli:decimalItemType
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Period Type:	duration

- Definition

The number of other equity instruments (ie other than share options) exercisable in a share-based payment arrangement.

+ References

+ Details

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Period Type:	instant

- Definition

The number of other equity instruments (ie other than share options) exercised or vested in a share-based payment arrangement.

+ References

+ Details

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Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of other equity instruments (ie other than share options) expired in a share-based payment arrangement.

+ References

+ Details

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Data Type:	xbrli:decimalItemType
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- Definition

The number of other equity instruments (ie other than share options) forfeited in a share-based payment arrangement.

+ References

+ Details

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Data Type:	xbrli:decimalItemType
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- Definition

The number of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement.

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+ Details

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Share-based compensation - Restricted share awards (Details)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2025 CHF (SFr) EquityInstruments	Jun. 30, 2024 CHF (SFr)	Jun. 30, 2025 CHF (SFr) EquityInstruments	Jun. 30, 2024 CHF (SFr) EquityInstruments	Dec. 31, 2024 CHF (SFr) EquityInstruments
Weighted Average grant date fair value [Abstract]
Expense charged against the income statement \| SFr	SFr 1,100,000	SFr 1,400,000	SFr 2,700,000	SFr 3,300,000
Restricted share awards
Number of non-vested shares [Abstract]
Vested and exercisable \| EquityInstruments	1,789,612		1,789,612		1,377,903
Weighted Average grant date fair value [Abstract]
Weighted average grant date fair value, vested and exercisable \| SFr	SFr 3.09		SFr 3.09		SFr 3.25
Restricted share awards, non-vested
Share-based payment arrangement [Abstract]
Number of non-vested share awards granted (in shares) \| EquityInstruments			1,303,342		1,094,876
Number of non-vested shares [Abstract]
Non-vested at beginning of period \| EquityInstruments			822,740	1,003,743	1,003,743
Forfeited during the period \| EquityInstruments			(74,085)		(97,841)
Exercised during the period \| EquityInstruments			(56,630)		(99,018)
Cancelled during the period \| EquityInstruments			(34,612)
Granted during the period \| EquityInstruments			1,303,342		1,094,876
Vested during the period \| EquityInstruments			(491,585)		(1,064,554)
Non-vested at end of period \| EquityInstruments	1,549,046		1,549,046		822,740
Weighted Average grant date fair value [Abstract]
Weighted average grant date fair value, non-vested at beginning of period \| SFr			SFr 3.12	SFr 1.97	SFr 1.97
Weighted average grant date fair value, forfeited during the period \| SFr			3.44		3.26
Weighted average grant date fair value, exercised during the period \| SFr			2.72		2.54
Weighted average grant date fair value, cancelled during the period \| SFr			2.04
Weighted average grant date fair value, granted during the period \| SFr			2.43		4.04
Weighted average grant date fair value, vested during the period \| SFr			2.6		3.05
Weighted average grant date fair value, non-vested at end of period \| SFr	SFr 2.72		SFr 2.72		SFr 3.12