The number of ordinary shares available for future issuance of share-based equity awards.

No definition available.

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- Definition

Remaining period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

No definition available.

+ Details

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- Definition

Share option award granted period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- 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 reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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

- Definition

The exercise price of share options granted.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
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-URIDate 2025-03-27

+ Details

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Data Type:	dtr-2022:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

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+ Details

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

- Definition

The number of shares authorised.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
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-IssueDate 2025-01-01
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-URIDate 2025-03-27

+ Details

Name:	ifrs-full_NumberOfSharesAuthorised
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of shares reserved for issue under options and contracts for the sale of shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
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-URIDate 2025-03-27

+ Details

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-URIDate 2025-03-27

+ Details

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Namespace Prefix:	ifrs-full_
Data Type:	dtr-2022:perShareItemType
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- Details

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- Details

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- Details

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- Details

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Share-based compensation, Share Options (Details)	12 Months Ended
Share-based compensation, Share Options (Details)	Dec. 31, 2025 shares $ / shares	Dec. 31, 2024 shares $ / shares	Dec. 31, 2023 shares	Jun. 30, 2021 shares
Share based payment arrangement [Abstract]
Number of shares reserved for future issuance (in shares)				1,202,734
Number of ordinary shares available for future issuance (in shares)	1,117,791	325,861	404,718
Number of options granted (in shares)	770,251	1,320,120	440,719
Weighted average share price of shares exercised (in dollars per share) \| $ / shares		$ 10.73
Key Management [Member]
Share based payment arrangement [Abstract]
Number of options granted (in shares)	494,001	1,043,120
Share Option, Expiration Period One [Member]
Share based payment arrangement [Abstract]
Number of options granted (in shares)	261,250
Award vest percentage	25.00%
Remaining vesting period	3 years
Vesting condition	2 years
Share option award granted period	8 years
Share Option, Expiration Period Two [Member]
Share based payment arrangement [Abstract]
Number of options granted (in shares)	14,001
Vesting condition	2 years
Share option award granted period	7 years
Exercise price for option granted (in dollars per share) \| $ / shares	$ 0.025
Share Option Expiration Period Three [Member]
Share based payment arrangement [Abstract]
Number of options granted (in shares)	495,000
Award vest percentage	25.00%
Remaining vesting period	3 years
Share option award granted period	7 years
Exercise price for option granted (in dollars per share) \| $ / shares	$ 0.025
Share Options [Member]
Share based payment arrangement [Abstract]
Number of shares authorized (in shares)	3,721,251