Share-based payments - Disclosure of share option and award plans (Details) £ / shares in Units, shares in Thousands	12 Months Ended
Dec. 31, 2025 GBP (£) shares £ / shares	Dec. 31, 2024 GBP (£) shares £ / shares	Dec. 31, 2023 shares
SVP and DSVP
Disclosure of terms and conditions of share-based payment arrangement [line items]
Weighted average fair value per award granted in year \| £	£ 2.87	£ 1.52
Weighted average share price at exercise/release during year (in GBP per share) \| £ / shares	£ 3.09	£ 1.74
Weighted average remaining contractual life	1 year	1 year
Number of options/awards outstanding (in shares) \| shares	381,279	441,713	435,820
Others
Disclosure of terms and conditions of share-based payment arrangement [line items]
Number of options/awards outstanding (in shares) \| shares	35,395	43,901	51,363
Others \| Bottom of range
Disclosure of terms and conditions of share-based payment arrangement [line items]
Weighted average fair value per award granted in year \| £	£ 1.49	£ 0.81
Weighted average share price at exercise/release during year (in GBP per share) \| £ / shares	£ 3.03	£ 1.72
Weighted average remaining contractual life	0 years	0 years
Others \| Top of range
Disclosure of terms and conditions of share-based payment arrangement [line items]
Weighted average fair value per award granted in year \| £	£ 3.57	£ 2.1
Weighted average share price at exercise/release during year (in GBP per share) \| £ / shares	£ 4.01	£ 2.13
Weighted average remaining contractual life	2 years	2 years

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 45
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2025-en-r&anchor=para_45_d&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 45
-Subparagraph b
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2025-en-r&anchor=para_45_b_i&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 45
-Subparagraph b
-Clause vi
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2025-en-r&anchor=para_45_b_vi&doctype=Standard
-URIDate 2025-03-27

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 31
-Subparagraph b
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_31_b_i&doctype=Standard
-URIDate 2025-03-27

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 31
-Subparagraph b
-Clause vi
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_31_b_vi&doctype=Standard
-URIDate 2025-03-27

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 31
-Subparagraph b
-Clause vi
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_31_b_vi&doctype=Standard
-URIDate 2025-03-27

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 31
-Subparagraph b
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_31_b_i&doctype=Standard
-URIDate 2025-03-27

+ Details

- Definition

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

+ References + Details