XML 137 R102.htm IDEA: XBRL DOCUMENT v3.21.1

Share-based payments, Growth share plan (Details)	12 Months Ended
	Dec. 31, 2020 shares GBP (£) £ / shares	Dec. 31, 2020 shares GBP (£) £ / shares	Dec. 31, 2020 shares GBP (£) £ / shares	Dec. 31, 2020 shares GBP (£) £ / shares	Dec. 31, 2020 shares GBP (£) £ / shares	Dec. 31, 2019 shares	Dec. 31, 2019 GBP (£)	Dec. 31, 2019 £ / shares	Dec. 31, 2018 shares	Dec. 31, 2018 GBP (£)	Dec. 31, 2018 £ / shares
Share-based payments awards [Abstract]
Share-based compensation arrangement by award vesting period	4 years
Share-based compensation arrangement by award vesting percentage					0.25
Employees [Member]
Share-based payments awards [Abstract]
Vesting period	7 years
Share option plan [Member]
Share-based payments awards [Abstract]
Share-based compensation arrangement by award vesting period	4 years
Share-based compensation arrangement by award vesting percentage					0.25
Vesting period	3 years
Number of options [Abstract]
Outstanding at beginning period (in shares) | shares		715,823				148,723			227,608
Awards granted (in shares)		224,536	224,536			582,252	582,252		0	0
Awards exercised (in shares) | shares		2,776				8,574			10,950
Awards forfeited (in shares) | shares		(27,311)				(6,578)			(67,935)
Outstanding at ending period (in shares) | shares		910,272				715,823			148,723
Exercisable at ending period (in shares) | shares	194,106	194,106	194,106	194,106	194,106
Weighted average exercise prices [Abstract]
Outstanding at beginning period (in pounds per share)				£ 132.89				£ 57.50			£ 54.01
Awards granted (in pounds per share)				64				150			0
Awards exercised (in pounds per share)				21.91				2.71			9.26
Awards forfeited (in pounds per share)				81.67				103.17			53.57
Outstanding at period end (in pounds per share)				62.90				132.89			57.50
Exercisable at ending period (in pounds per share)	£ 91.92	£ 91.92	£ 91.92	£ 91.92	£ 91.92
Share option plan [Member] | Employees [Member]
Share-based payments awards [Abstract]
Share-based compensation arrangement by award vesting period	8 years
Share-based compensation arrangement by award vesting percentage					0.125
Growth share plan [Member]
Share-based payments awards [Abstract]
Share-based compensation arrangement by award vesting period	4 years
Share-based compensation arrangement by award vesting percentage					0.25
Vesting period	3 years
Number of options [Abstract]
Outstanding at beginning period (in shares) | £			58,206				118,446			155,246
Awards granted (in shares) | £			34,260				0			0
Awards exercised (in shares) | £			0				0			0
Awards forfeited (in shares) | £			(29,575)				(60,240)			(36,800)
Outstanding at ending period (in shares) | £			62,891				58,206			118,446
Exercisable at ending period (in shares) | £	34,857	34,857	34,857	34,857	34,857
Weighted average exercise prices [Abstract]
Outstanding at beginning period (in pounds per share)				£ 170.00				170.00			170.00
Awards granted (in pounds per share)				110.41				0			0
Awards exercised (in pounds per share)				0				0			0
Awards forfeited (in pounds per share)				170.00				170.00			170.00
Outstanding at period end (in pounds per share)				137.54				£ 170.00			£ 170.00
Exercisable at ending period (in pounds per share)	£ 157.83	£ 157.83	£ 157.83	£ 157.83	£ 157.83
Growth share plan [Member] | Employees [Member]
Share-based payments awards [Abstract]
Share-based compensation arrangement by award vesting period	8 years
Share-based compensation arrangement by award vesting percentage					0.125
Vesting period	7 years

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2020-01-01
-Paragraph 45
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_d&doctype=Standard
-URIDate 2020-01-01

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2020-01-01
-Paragraph 45
-Subparagraph b
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_i&doctype=Standard
-URIDate 2020-01-01

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2020-01-01
-Paragraph 45
-Subparagraph b
-Clause vi
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_vi&doctype=Standard
-URIDate 2020-01-01

+ Details

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

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2020-01-01
-Paragraph 45
-Subparagraph b
-Clause vii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_vii&doctype=Standard
-URIDate 2020-01-01

+ Details

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

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2020-01-01
-Paragraph 45
-Subparagraph b
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_iv&doctype=Standard
-URIDate 2020-01-01

+ Details

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

X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2020-01-01
-Paragraph 45
-Subparagraph b
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_iii&doctype=Standard
-URIDate 2020-01-01

+ Details

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

X

- 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 2020-01-01
-Paragraph 45
-Subparagraph b
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_ii&doctype=Standard
-URIDate 2020-01-01

+ Details

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

X

- Definition

The weighted average exercise price of share options exercisable 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 2020-01-01
-Paragraph 45
-Subparagraph b
-Clause vii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_vii&doctype=Standard
-URIDate 2020-01-01

+ Details

Name:	ifrs-full_WeightedAverageExercisePriceOfShareOptionsExercisableInSharebasedPaymentArrangement2019
Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

X

- Definition

The weighted average exercise price of share options exercised 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 2020-01-01
-Paragraph 45
-Subparagraph b
-Clause iv
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_iv&doctype=Standard
-URIDate 2020-01-01

+ Details

Name:	ifrs-full_WeightedAverageExercisePriceOfShareOptionsExercisedInSharebasedPaymentArrangement2019
Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The weighted average exercise price of share options forfeited 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 2020-01-01
-Paragraph 45
-Subparagraph b
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_iii&doctype=Standard
-URIDate 2020-01-01

+ Details

Name:	ifrs-full_WeightedAverageExercisePriceOfShareOptionsForfeitedInSharebasedPaymentArrangement2019
Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

X

- 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 2020-01-01
-Paragraph 45
-Subparagraph b
-Clause ii
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_ii&doctype=Standard
-URIDate 2020-01-01

+ Details

Name:	ifrs-full_WeightedAverageExercisePriceOfShareOptionsGrantedInSharebasedPaymentArrangement2019
Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The weighted average exercise price of share options outstanding 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 2020-01-01
-Paragraph 45
-Subparagraph b
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_i&doctype=Standard
-URIDate 2020-01-01

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2020-01-01
-Paragraph 45
-Subparagraph b
-Clause vi
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_45_b_vi&doctype=Standard
-URIDate 2020-01-01

+ Details

Name:	ifrs-full_WeightedAverageExercisePriceOfShareOptionsOutstandingInSharebasedPaymentArrangement2019
Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

X

- References

No definition available.

+ Details

Name:	imcr_NumberOfOptionsAbstract
Namespace Prefix:	imcr_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

No definition available.

+ Details

Name:	imcr_ShareBasedCompensationArrangementByAwardVestingPercentage
Namespace Prefix:	imcr_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

X

- Definition

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

Name:	imcr_ShareBasedCompensationArrangementByAwardVestingPeriod
Namespace Prefix:	imcr_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

Name:	imcr_ShareBasedPaymentsAwardsAbstract
Namespace Prefix:	imcr_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The term of options vested for a type of share-based payment arrangement that existed at any time during the period.

+ References

No definition available.

+ Details

Name:	imcr_TermOfOptionVestingForShareBasedPaymentArrangement
Namespace Prefix:	imcr_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

Name:	imcr_WeightedAverageExercisePricesAbstract
Namespace Prefix:	imcr_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	ifrs-full_CategoriesOfRelatedPartiesAxis=imcr_EmployeesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=imcr_ShareOptionPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	ifrs-full_TypesOfSharebasedPaymentArrangementsAxis=imcr_GrowthSharePlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: