Analysis of the net investment in business interests and intangible assets (Details) - GBP (£) £ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Analysis of the net investment in business interests and intangible assets
Fair value given for businesses acquired		£ (55)	£ (113)
Additional investment in associates	£ (40)		(9)
Net outflow of cash in respect of acquisitions	(40)	(55)	(122)
Sale of interests in associates	27
Net assets sold	288	351
Profit on disposals	3
Net inflow of cash in respect of disposals	318	351
Dividends received from associates			5
Cash expenditure on intangible assets	(348)	(380)	(364)
Net outflow of cash	£ (70)	£ (84)	£ (481)

The fair value, at acquisition date, of the consideration transferred in a business combination. [Refer: Business combinations [member]]

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The aggregate cash flows used in obtaining control of subsidiaries or other businesses, classified as investing activities. [Refer: Subsidiaries [member]]

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The amount of consideration paid or received in respect of both obtaining and losing control of subsidiaries or other businesses. [Refer: Subsidiaries [member]]

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The cash inflow representing dividends received from associates, classified as investing activities. [Refer: Associates [member]; Dividends received]

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The amount of liabilities in subsidiaries or other businesses over which control is obtained or lost. [Refer: Subsidiaries [member]]

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The cash inflow from sales of interests in associates. [Refer: Associates [member]]

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The cash outflow for the purchases of intangible assets, classified as investing activities. [Refer: Intangible assets other than goodwill]

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The cash outflow for the purchase of interests in associates. [Refer: Associates [member]]

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The cash inflow (outflow) due to the (investment in) divestment of business interests and intangible assets.

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