S000052306 [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 |
Dec. 31, 2018 |
Dec. 31, 2017 |
|
| UBS Prime Reserves Fund | UBS Prime Reserves Fund | |||||||||
| Prospectus [Line Items] | |||||||||
| Annual Return [Percent] | 4.23% | 5.21% | 5.13% | 1.63% | 0.01% | 0.52% | 2.21% | 1.89% | 0.98% |