Label	Element	Value
UBS Municipal Bond Fund
Risk/Return:	rr_RiskReturnAbstract
Supplement to Prospectus [Text Block]	rr_SupplementToProspectusTextBlock	The UBS Funds Prospectus Supplement \| January 10, 2022 Includes: • UBS Municipal Bond Fund Dear Investor, The purpose of this supplement is to update the information in the Prospectus relating to Class A and Class P shares, dated October 28, 2021, for UBS Municipal Bond Fund, a series of The UBS Funds, as follows:
Risk/Return [Heading]	rr_RiskReturnHeading	UBS Municipal Bond Fund
Performance Table Market Index Changed	rr_PerformanceTableMarketIndexChanged	On page 52 of the Prospectus, the returns for the Fund's secondary benchmark, the Bloomberg Municipal Managed Money Intermediate (1-17) Index, for the 1 year, 5 years and Life of class periods that appear in the "Average annual total returns" table are replaced with the following:
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	On page 52 of the Prospectus, the returns for the Fund's secondary benchmark, the Bloomberg Municipal Managed Money Intermediate (1-17) Index, for the 1 year, 5 years and Life of class periods that appear in the "Average annual total returns" table are replaced with the following:
Performance Table Closing [Text Block]	rr_PerformanceTableClosingTextBlock	PLEASE BE SURE TO RETAIN THIS IMPORTANT INFORMATION FOR FUTURE REFERENCE.
UBS Municipal Bond Fund \| Bloomberg Municipal Managed Money Intermediate (1-17) Index
Risk/Return:	rr_RiskReturnAbstract
Average Annual Returns, 1 Year	rr_AverageAnnualReturnYear01	5.70%
Average Annual Returns, 5 Years	rr_AverageAnnualReturnYear05	3.69%
Average Annual Returns, Since Inception	rr_AverageAnnualReturnSinceInception	3.69%

Return Before Taxes.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii
-Clause 1
-Exhibit 2

+ Details

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Return Before Taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii
-Clause 1
-Exhibit 2

+ Details

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- Definition

Return Before Taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii
-Clause 1
-Exhibit 2

+ Details

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- Definition

If the Fund has annual returns for at least one calendar year, provide a table showing the Fund's (A) average annual total return; (B) average annual total return (after taxes on distributions); and (C) average annual total return (after taxes on distributions and redemption). A Money Market Fund should show only the returns described in clause (A) of the preceding sentence. All returns should be shown for 1-, 5-, and 10- calendar year periods ending on the date of the most recently completed calendar year (or for the life of the Fund, if shorter), but only for periods subsequent to the effective date of the Fund's registration statement. The table also should show the returns of an appropriate broad-based securities market index as defined in Instruction 5 to Item 22(b)(7) for the same periods. A Fund that has been in existence for more than 10 years also may include returns for the life of the Fund. A Money Market Fund may provide the Fund's 7-day yield ending on the date of the most recent calendar year or disclose a toll-free (or collect) telephone number that investors can use to obtain the Fund's current 7-day yield. For a Fund (other than a Money Market Fund or a Fund described in General Instruction C.3.(d)(iii)), provide the information in the following table with the specified captions AVERAGE ANNUAL TOTAL RETURNS (For the periods ended December 31, _____)

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iii

+ Details

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- Definition

If the Fund selects an index that is different from the index used in a table for the immediately preceding period, explain the reason(s) for the selection of a different index and provide information for both the newly selected and the former index.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph instructions
-Clause 2
-Exhibit c

+ Details

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 4
-Subsection b
-Paragraph 2
-Subparagraph iv

+ Details

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- References

No definition available.

+ Details

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Risk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicated

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 2

+ Details

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- Definition

This element contains the text of a prospectus supplement (submission type 497) not already contained in an element containing amended text or other data from a previous submission.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A

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