Performance Management - Short Term Investment Fund for Puerto Rico Residents, Inc. |
Jun. 30, 2026 |
|---|---|
| Prospectus [Line Items] | |
| Bar Chart and Performance Table [Heading] | Performance Information |
| Performance Narrative [Text Block] | The information below shows you how the Fund’s performance has varied year by year over the prior ten‑year period and provides some indication of the risks of investing in the Fund. The chart and the table below give you a picture only of the long-term performance for the Class A Shares of the Fund. The performance of the Class B Shares would be the same as the Class A Shares because the Class B Shares and the Class A Shares are invested in the same portfolio of securities, however Class A Shares and Class B Shares have different expenses. The table below compares the Fund’s performance to that of the Bloomberg U.S. Aggregate Bond Index (the “Benchmark Index”) and the ICE BofA US 3‑Month Treasury Bill Index (the “Secondary Index”). The Secondary Index is relevant to the Fund because it has characteristics similar to the Fund’s investment strategy. To the extent that dividends and distributions have been paid by the Fund, the performance information for the Fund in the chart and table assumes reinvestment of the dividends and distributions. As with all such investments, past performance (before and after taxes) is not an indication of future results. The table includes all applicable fees, after giving effect to fee waivers and reimbursements. If UBS Trust Company of Puerto Rico had not waived or reimbursed certain Fund expenses during these periods, the Fund’s returns would have been lower. Updated information on the Fund’s performance can be obtained by visiting www.ubs.com/prfunds or can be obtained by phone at (787) 250‑3600. The Fund’s financial performance included in this prospectus includes the Fund’s performance from a period when the Fund was not subject to the restrictions of a U.S. registered investment company that is subject to the requirements of the 1940 Act and when the Fund invested pursuant to different investment strategies. The Benchmark Index measures the investment grade, US dollar-denominated, fixed-rate taxable bond market. The Secondary Index measures the performance of a single issue of outstanding treasury bill which matures closest to, but not beyond, three months from the rebalancing date. The issue is purchased at the beginning of the month and held for a full month; at the end of the month that issue is sold and rolled into a newly selected issue.
|
| Performance Past Does Not Indicate Future [Text] | As with all such investments, past performance (before and after taxes) is not an indication of future results. |
| Performance Information Illustrates Variability of Returns [Text] | The information below shows you how the Fund’s performance has varied year by year over the prior ten‑year period and provides some indication of the risks of investing in the Fund. |
| Performance Additional Market Index [Text] | The table below compares the Fund’s performance to that of the Bloomberg U.S. Aggregate Bond Index (the “Benchmark Index”) and the ICE BofA US 3‑Month Treasury Bill Index (the “Secondary Index”). The Secondary Index is relevant to the Fund because it has characteristics similar to the Fund’s investment strategy. |
| Bar Chart [Heading] | CLASS A SHARES ANNUAL TOTAL RETURNS As of 12/31 |
| Bar Chart Closing [Text Block] | During the ten‑year period shown in the bar chart, the highest return for a quarter was 1.49% (quarter ended December 31, 2023) and the lowest return for a quarter was 0.00% (quarter ended March 31, 2021). The year‑to‑date return as of September 30, 2026, was 2.00%.
|
| Performance Table Heading | For the periods ended 12/31/25Average Annual Total Returns |
| Performance Table Narrative | After‑tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after‑tax returns depend on an investor’s tax situation and may differ from those shown. In addition, the after‑tax returns shown are not relevant to investors who hold Fund shares through tax‑deferred or tax‑advantaged arrangements, such as 401(k) plans or individual retirement accounts. After tax returns are shown for Class A Shares only and the after tax returns for Class B will vary.
|
| Performance Table Uses Highest Federal Rate | After‑tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. |
| Performance Table Not Relevant to Tax Deferred | Actual after‑tax returns depend on an investor’s tax situation and may differ from those shown. In addition, the after‑tax returns shown are not relevant to investors who hold Fund shares through tax‑deferred or tax‑advantaged arrangements, such as 401(k) plans or individual retirement accounts. |
| Performance Table One Class of after Tax Shown [Text] | After tax returns are shown for Class A Shares only and the after tax returns for Class B will vary. |
| Performance Availability Website Address [Text] | www.ubs.com/prfunds |
| Performance Availability Phone [Text] | (787) 250‑3600 |
| Class A | |
| Prospectus [Line Items] | |
| Year to Date Return, Label [Optional Text] | year‑to‑date return |
| Bar Chart, Year to Date Return | 2.00% |
| Bar Chart, Year to Date Return, Date | Sep. 30, 2026 |
| Highest Quarterly Return, Label [Optional Text] | highest return |
| Highest Quarterly Return | 1.49% |
| Highest Quarterly Return, Date | Dec. 31, 2023 |
| Lowest Quarterly Return, Label [Optional Text] | lowest return |
| Lowest Quarterly Return | none |
| Lowest Quarterly Return, Date | Mar. 31, 2021 |