S000084283 [Member] Expense Example - UBS Select 100% US Treasury Preferred Fund	Apr. 30, 2025 USD ($)
Class P
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 14
Expense Example, with Redemption, 3 Years	63
Expense Example, with Redemption, 5 Years	116
Expense Example, with Redemption, 10 Years	272
Class T
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	14
Expense Example, with Redemption, 3 Years	63
Expense Example, with Redemption, 5 Years	116
Expense Example, with Redemption, 10 Years	$ 272

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 3
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 1
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