v3.26.1
Class Aand Class P [Member] Annual Total Returns
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Class A and Class P | UBS Ultra Short Income Fund | Class A              
Prospectus [Line Items]              
Annual Return [Percent] 4.53% 5.31% 5.61% (0.19%) (0.14%) 0.81% 2.79%