No definition available.

Name:	aciu_OutstandingOptionsExercisePriceRangeAndExpiryDatesAbstract
Namespace Prefix:	aciu_
Data Type:	xbrli:stringItemType
Balance Type:	na
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- Definition

The date on which share options will expired.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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

- Definition

The weighted average exercise price of share options granted in a share-based payment arrangement. [Refer: Weighted average [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2021-01-01
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-URIDate 2021-03-24

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The weighted average share price at the date of exercise for share options that are exercised in a share-based payment arrangement. [Refer: Share-based payment arrangements [member]; Weighted average [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-URIDate 2021-03-24

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Share-based compensation, Outstanding Options, Range of Exercise prices and Expiration Dates (Details)	12 Months Ended
	Dec. 31, 2021 shares SFr / shares	Dec. 31, 2021 shares $ / shares	Dec. 31, 2020 shares SFr / shares	Dec. 31, 2020 shares $ / shares	Dec. 31, 2019 shares SFr / shares	Dec. 31, 2019 shares $ / shares	Dec. 31, 2018 shares
Outstanding options, exercise price range and expiry dates [Abstract]
Outstanding Options (in shares)	3,585,689	3,585,689	2,900,667	2,900,667	1,981,629	1,981,629	1,618,856
Weighted average exercise price for options granted (in CHF/USD per share) \| (per share)	SFr 6.34	$ 6.95	SFr 6.29	$ 7.11	SFr 5.24	$ 5.41
Weighted average share price of common share options exercised (in dollars per share) \| (per share)	6.62	7.26
Bottom of Range [Member]
Outstanding options, exercise price range and expiry dates [Abstract]
Weighted average exercise price for options granted (in CHF/USD per share) \| (per share)	0.15	5.04			SFr 5.24
Top of Range [Member]
Outstanding options, exercise price range and expiry dates [Abstract]
Weighted average exercise price for options granted (in CHF/USD per share) \| (per share)	SFr 9.53	$ 12.30
CHF 0.15 [Member]
Outstanding options, exercise price range and expiry dates [Abstract]
Outstanding Options (in shares)	208,125	208,125
CHF 0.15 [Member] \| Bottom of Range [Member]
Outstanding options, exercise price range and expiry dates [Abstract]
Expiration Dates	2022	2022
CHF 0.15 [Member] \| Top of Range [Member]
Outstanding options, exercise price range and expiry dates [Abstract]
Expiration Dates	2026	2026
CHF 9.53 [Member]
Outstanding options, exercise price range and expiry dates [Abstract]
Outstanding Options (in shares)	223,646	223,646
Expiration Dates	2027	2027
USD 5.04 to USD 12.30 [Member]
Outstanding options, exercise price range and expiry dates [Abstract]
Outstanding Options (in shares)	3,153,918	3,153,918
USD 5.04 to USD 12.30 [Member] \| Bottom of Range [Member]
Outstanding options, exercise price range and expiry dates [Abstract]
Expiration Dates	2028	2028
USD 5.04 to USD 12.30 [Member] \| Top of Range [Member]
Outstanding options, exercise price range and expiry dates [Abstract]
Expiration Dates	2031	2031