MD&A - UBS shares (Narrative) (Detail) - SFr / shares	Dec. 31, 2019	Dec. 31, 2018
Disclosure of Shares [Line Items]
Par value of shares	SFr 0.1	SFr 0.1
UBS AG
Disclosure of Shares [Line Items]
Par value of shares	SFr 0.1	SFr 0.1

The nominal value per share.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2018-01-01
-Paragraph 79
-Subparagraph a
-Clause iii
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=1&date=2018-03-01&anchor=para_79_a_iii&doctype=Standard
-URIDate 2018-03-16

Name:	ifrs-full_ParValuePerShare
Namespace Prefix:	ifrs-full_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant