Investments in associates and joint ventures - Narrative (Details) £ in Millions	12 Months Ended
Jun. 30, 2020 GBP (£) € / £	Jun. 30, 2019 GBP (£) € / £	Jun. 30, 2018 € / £
Disclosure of associates [line items]
Cost of shares less goodwill written off on acquisitions	£ 1,312	£ 1,249
Group's share of post acquisition reserves	£ 2,245	£ 1,924
Moet Hennessy
Disclosure of associates [line items]
Ownership interest in associate	34.00%
Country of incorporation	France
Average exchange rate (EUR per GBP) \| € / £	1.14	1.13	1.13

Cost of shares less goodwill written off on acquisitions of investments in associates and joint ventures.

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- Definition

Groups share of post acquisition reserves.

+ References

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- Definition

The average exchange rate used by the entity. Exchange rate is the ratio of exchange for two currencies.

+ References

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- Definition

The country in which an associate of the entity is incorporated. [Refer: Associates [member]]

+ References

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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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The proportion of ownership interest in an associate attributable to the entity. [Refer: Associates [member]]

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