Post employment benefits - Balance sheet analysis of post employment plans (Parenthetical) (Detail) - GBP (£) £ in Millions	Jun. 30, 2019	Jun. 30, 2018
Disclosure of defined benefit plans [abstract]
Surplus restriction	£ 1	£ 3

The asset ceiling is the present value of any economic benefits available in the form of refunds from the plan or reduction in future contributions to the plan.

No definition available.

Name:	deo_EffectOfAssetCeiling
Namespace Prefix:	deo_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant