Finance lease receivables (Narrative) (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Disclosure Of Finance Lease And Operating Lease By Lessor [Line Items]
Explanation Of Unguaranteed Residual Values Accruing To Benefit Of Lessor	USD 246 million	USD 156 million
Accumulated Allowance For Uncollectible Minimum Lease Payments Receivable	$ 6	$ 7
Contingent Rents Recognised As Income	$ 0
UBS AG
Disclosure Of Finance Lease And Operating Lease By Lessor [Line Items]
Explanation Of Unguaranteed Residual Values Accruing To Benefit Of Lessor	USD 246 million	USD 156 million
Accumulated Allowance For Uncollectible Minimum Lease Payments Receivable	$ 6	$ 7
Contingent Rents Recognised As Income	$ 0

The amount of accumulated allowance for uncollectible minimum lease payments receivable. Minimum lease payments are payments over the lease term that the lessee is or can be required to make, excluding contingent rent, costs for services and taxes to be paid by and reimbursed to the lessor, together with: (a) for a lessee, any amounts guaranteed by the lessee or by a party related to the lessee; or (b) for a lessor, any residual value guaranteed to the lessor by: (i) the lessee; (ii) a party related to the lessee; or (iii) a third party unrelated to the lessor that is financially capable of discharging the obligations under the guarantee.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2019-01-01
-Name IAS
-Number 17
-IssueDate 2018-01-01
-Paragraph 47
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=17&date=2018-03-02&anchor=para_47_d&doctype=Standard&book=b
-URIDate 2018-03-16

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- Definition

The portion of lease payments recognised as income that is not fixed in amount but is based on the future amount of a factor that changes other than with the passage of time (for example, percentage of future sales, amount of future use, future price indices, future market rates of interest).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2019-01-01
-Name IAS
-Number 17
-IssueDate 2018-01-01
-Paragraph 47
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=17&date=2018-03-02&anchor=para_47_e&doctype=Standard&book=b
-URIDate 2018-03-16

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2019-01-01
-Name IAS
-Number 17
-IssueDate 2018-01-01
-Paragraph 56
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=17&date=2018-03-02&anchor=para_56_b&doctype=Standard&book=b
-URIDate 2018-03-16

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- Definition

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.

+ References

No definition available.

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- Definition

The explanation of unguaranteed residual values accruing to the benefit of the lessor. Unguaranteed residual value is that portion of the residual value of the leased asset, the realisation of which by the lessor is not assured or is guaranteed solely by a party related to the lessor.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2019-01-01
-Name IAS
-Number 17
-IssueDate 2018-01-01
-Paragraph 47
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=17&date=2018-03-02&anchor=para_47_c&doctype=Standard&book=b
-URIDate 2018-03-16

+ Details

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