Basis of accounting (Narrative) (Detail)	6 Months Ended
Jun. 30, 2022
Entity [Table]
Sale of the proportion of the shareholding in Mitsubishi Corp.-UBS Realty Inc, held by UBS	49.00%

The sale of the proportion of the shareholding in Mitsubishi Corp.-UBS Realty Inc, held by UBS.

No definition available.

Name:	ubs_SaleOfTheProportionOfTheShareholdingInMitsubishiCorpUbsRealtyIncHeldByUbs
Namespace Prefix:	ubs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration