Capital structure and financing - C.7.3. Equity investments (Details) - Equity Investment In HTA £ in Millions, shares in Millions, $ in Millions	1 Months Ended	12 Months Ended	13 Months Ended
Jun. 30, 2021 GBP (£) shares	Jun. 30, 2021 USD ($) shares	Dec. 31, 2020 GBP (£) shares	Dec. 31, 2020 USD ($) shares	Jul. 01, 2021 GBP (£) shares	Jul. 01, 2021 USD ($) shares
Disclosure of fair value measurement of assets [line items]
Number of shares sold (in shares) \| shares	76	76	85	85	162	162
Proceeds from sales of investments accounted for using equity method	£ 115	$ 163	£ 130	$ 169	£ 244	$ 383
Gain (loss) on disposal of equity method investment \| $		$ (15)		$ 6

The cash inflow from sales of investments accounted for using the equity method. [Refer: Investments accounted for using equity method]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 7
-IssueDate 2022-03-24
-Paragraph 16
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=7&code=ifrs-tx-2022-en-r&anchor=para_16&doctype=Standard
-URIDate 2022-03-24

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