Financial instruments - Level 3 (Detail) - Level 3 £ in Millions	6 Months Ended
Jun. 30, 2022 GBP (£)
Changes in fair value measurement, assets [abstract]
Beginning balance	£ 290.0
(Losses)/gains recognised in the income statement	9.0
Gains recognised in other comprehensive income	3.6
Additions	66.7
Disposals	(16.0)
Cancellations	0.0
Settlements	0.0
Exchange adjustments	0.0
Ending balance	353.3
Payments due to vendors (earnout agreements)
Reconciliation of changes in fair value measurement, liabilities [abstract]
Beginning balance	(196.7)
(Losses)/gains recognised in the income statement	(1.1)
Gains recognised in other comprehensive income	0.0
Additions	(22.6)
Disposals	0.0
Cancellations	0.0
Settlements	63.3
Exchange adjustments	(16.0)
Ending balance	(173.1)
Liabilities in respect of put options
Reconciliation of changes in fair value measurement, liabilities [abstract]
Beginning balance	(391.5)
(Losses)/gains recognised in the income statement	19.6
Gains recognised in other comprehensive income	0.0
Additions	0.0
Disposals	0.0
Cancellations	5.0
Settlements	5.8
Exchange adjustments	(36.7)
Ending balance	£ (397.8)

No definition available.

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Period Type:	duration

- Definition

The amount of assets that are: (a) cash; (b) an equity instrument of another entity; (c) a contractual right: (i) to receive cash or another financial asset from another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially favourable to the entity; or (d) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to receive a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose the entity’s own equity instruments do not include puttable financial instruments classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. [Refer: Financial instruments, class [member]; Financial liabilities]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 35H
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_35H&doctype=Standard
-URIDate 2022-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 35M
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_35M&doctype=Standard
-URIDate 2022-03-24

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 35N
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_35N&doctype=Standard
-URIDate 2022-03-24

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 35I
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_35I&doctype=Standard
-URIDate 2022-03-24

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 25
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_25&doctype=Standard
-URIDate 2022-03-24