The maximum term of options granted for a type of share-based payment arrangement that existed at any time during the period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

+ Details

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Period Type:	duration

- Definition

Number of equity-based instrument plans approved by the entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	aciu_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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- Definition

For vesting requirements for a type of share-based payment arrangement that existed at any time during the period, this element represents the period which an employees' right to exercise an award is no longer contingent on satisfaction of a service condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	aciu_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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- Definition

The number of share options granted in a share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2021-01-01
-Paragraph 45
-Subparagraph b
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2021-en-r&anchor=para_45_b_ii&doctype=Standard
-URIDate 2021-03-24

+ Details

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

- Details

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- Details

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- Details

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- Details

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Share-based compensation, Plans Outstanding (Details)	12 Months Ended
Share-based compensation, Plans Outstanding (Details)	Dec. 31, 2021 shares Plan	Dec. 31, 2020 shares	Dec. 31, 2019 shares
Share-based compensation [Abstract]
Number of equity-based instrument plans \| Plan	4
Share-based plans outstanding [Abstract]
Number of options awarded (in shares)	1,110,914	1,073,027	1,053,305
Share Option Plan C1 [Member]
Share-based plans outstanding [Abstract]
Number of options awarded (in shares)	6,775,250
Vesting conditions	4 years
Contractual life of options	10 years
2016 SOIP [Member] \| Executives and Directors [Member]
Share-based plans outstanding [Abstract]
Number of options awarded (in shares)	2,643,984
Contractual life of options	10 years
2016 SOIP [Member] \| Employees [Member]
Share-based plans outstanding [Abstract]
Number of options awarded (in shares)	1,354,431
Vesting conditions	4 years
Contractual life of options	10 years
2016 SOIP, Vesting Condition 1 [Member] \| Executives and Directors [Member]
Share-based plans outstanding [Abstract]
Vesting conditions	1 year
2016 SOIP, Vesting Condition 2 [Member] \| Executives and Directors [Member]
Share-based plans outstanding [Abstract]
Vesting conditions	3 years
2016 SOIP, Vesting Condition 3 [Member] \| Executives and Directors [Member]
Share-based plans outstanding [Abstract]
Vesting conditions	4 years