Segmental information - Category analysis (Details) - GBP (£) £ in Millions	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Disclosure of products and services [line items]
Sales	£ 17,697	£ 19,294	£ 18,432
Spirits
Disclosure of products and services [line items]
Sales	14,158	15,283	14,605
Beer
Disclosure of products and services [line items]
Sales	2,342	2,758	2,647
Ready to drink
Disclosure of products and services [line items]
Sales	966	945	854
Other
Disclosure of products and services [line items]
Sales	£ 231	£ 308	£ 326

The amount of revenue from contracts with customers. A customer is a party that has contracted with an entity to obtain goods or services that are an output of the entity’s ordinary activities in exchange for consideration.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 15
-IssueDate 2019-01-01
-Paragraph 113
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2019-en-r&anchor=para_113_a&doctype=Standard
-URIDate 2019-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 15
-IssueDate 2019-01-01
-Paragraph 114
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2019-en-r&anchor=para_114&doctype=Standard
-URIDate 2019-03-27

Name:	ifrs-full_RevenueFromContractsWithCustomers
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration