The amount of client assets seized by the court.

No definition available.

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- Definition

The amount of compensatory claim to be paid.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Damages award announced in the verdict of the Geneva criminal court.

+ References

No definition available.

+ Details

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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.

+ Details

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- Definition

The amount of estimated losses not covered by existing provisions.

+ References

No definition available.

+ Details

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Namespace Prefix:	ubsag_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fine decision Swiss Federal Criminal Court.

+ References

No definition available.

+ Details

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

No definition available.

+ Details

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Namespace Prefix:	ubsag_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The minimum amount of total claims against all defendants.

+ References

No definition available.

+ Details

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Namespace Prefix:	ubsag_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Revised damages award announced in the verdict of the Singapore International Commercial Court.

+ References

No definition available.

+ Details

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Namespace Prefix:	ubsag_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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- Details

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- Details

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Litigation, regulatory and similar matters (Narrative) (Detail) - 6 months ended Jun. 30, 2026 SFr in Millions, $ in Millions, € in Billions	CHF (SFr)	EUR (€)	USD ($)
Minimum
Disclosure Of Litigation Regulatory And Similar Matters [Line Items]
Estimated losses not covered by existing provisions			$ 0
Maximum
Disclosure Of Litigation Regulatory And Similar Matters [Line Items]
Estimated losses not covered by existing provisions			1,600
Madoff \| claims filed in Luxembourg by liquidators of two Luxembourg funds against UBS entities, non-UBS entities and certain individuals \| UBS
Disclosure Of Litigation Regulatory And Similar Matters [Line Items]
Minimum total claims against all defendants \| €		€ 2.1
Madoff \| claims filed in the US by BMIS Trustee against UBS entities and various other parties \| UBS
Disclosure Of Litigation Regulatory And Similar Matters [Line Items]
Minimum total claims against all defendants			2,000
Amounts claimed			125
Mortgage-related matters \| Action brought by Asset Backed Securities Corporation Home Equity Loan Trust, Series 2006-HE7 \| Credit Suisse
Disclosure Of Litigation Regulatory And Similar Matters [Line Items]
Amounts claimed			374
Mortgage-related matters \| Action brought by Home Equity Asset Trust, Series 2006-8 \| Credit Suisse
Disclosure Of Litigation Regulatory And Similar Matters [Line Items]
Amounts claimed			436
Mortgage-related matters \| Action brought by Home Equity Asset Trust 2007-2 \| Credit Suisse
Disclosure Of Litigation Regulatory And Similar Matters [Line Items]
Amounts claimed			495
Customer account matters \| Former relationship manager \| Credit Suisse
Disclosure Of Litigation Regulatory And Similar Matters [Line Items]
Damage award Geneva criminal court			130
Customer account matters \| Singapore civil lawsuits \| Credit Suisse
Disclosure Of Litigation Regulatory And Similar Matters [Line Items]
Revised damage award Singapore International Commercial Court			$ 461
Bulgarian former client matter \| Credit Suisse
Disclosure Of Litigation Regulatory And Similar Matters [Line Items]
Fine decision Swiss Federal Criminal Court \| SFr	SFr 2
Client assets seized decision Swiss Federal Criminal Court \| SFr	12
Compensatory claim ordered decision Swiss Federal Criminal Court \| SFr	SFr 19