GMO Alternative Allocation Fund Performance Management - GMO Alternative Allocation Fund |
Feb. 28, 2025 |
|---|---|
| Prospectus [Line Items] | |
| Bar Chart and Performance Table [Heading] | <span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;">Performance</span> |
| Performance Narrative [Text Block] | The bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund’s annual total returns from year to year for the periods indicated and by comparing the Fund’s average annual total returns for different calendar periods with those of the FTSE 3-Month Treasury Bill Index and a broad-based securities market index. Share classes not shown would have substantially similar annual returns to those below because all share classes invest in the same portfolio of securities. Annual returns vary among share classes to the extent that they bear different expenses. Share classes that bear higher expenses than the share classes shown below would have lower returns. 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 your tax situation and may differ from those shown. After-tax returns shown are not relevant if you are tax-exempt or if you hold your Fund shares through tax-advantaged arrangements (such as a 401(k) plan or individual retirement account). After-tax returns are shown for Class VI shares only; after-tax returns for other classes will vary. Updated performance information for the Fund is available at www.gmo.com. Past performance (before and after taxes) is not an indication of future performance. |
| Performance Past Does Not Indicate Future [Text] | <span style="color:#000000;font-family:Times New Roman;font-size:10pt;">Past performance (before and after taxes) is not an indication of future performance.</span> |
| Performance Information Illustrates Variability of Returns [Text] | <span style="color:#000000;font-family:Times New Roman;font-size:10pt;margin-left:3.76%;">The bar chart and table below provide some indication of the risks of investing in the Fund by showing changes in the Fund’s </span><span style="color:#000000;font-family:Times New Roman;font-size:10pt;">annual total returns from year to year for the periods indicated and by comparing the Fund’s average annual total returns for different calendar periods with those of the FTSE 3-Month Treasury Bill Index and a broad-based securities market index.</span> |
| Bar Chart [Heading] | <span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;">Annual Total Returns/Class VI Shares</span><span style="color:#000000;font-family:Times New Roman;font-size:6.5pt;font-weight:bold;position:relative;top:-2.75pt;">1</span> <br/><span style="color:#000000;font-family:Times New Roman;font-size:10pt;">Years Ending December 31</span> |
| Bar Chart Closing [Text Block] | Highest Quarter:4.76%Lowest Quarter:-6.99%Year-to-Date:5.13%As of3/31/2025 |
| Performance Table Heading | <span style="color:#000000;font-family:Times New Roman;font-size:10pt;font-weight:bold;">Average Annual Total Returns</span><span style="color:#000000;font-family:Times New Roman;font-size:6.5pt;font-weight:bold;position:relative;top:-2.75pt;">1</span> <br/><span style="color:#000000;font-family:Times New Roman;font-size:10pt;">Periods Ending December 31, 2024</span> |
| Performance Table Uses Highest Federal Rate | <span style="color:#000000;font-family:Times New Roman;font-size:10pt;">After-tax returns are calculated using the historical highest individual federal </span><span style="color:#000000;font-family:Times New Roman;font-size:10pt;">marginal income tax rates and do not reflect the impact of state and local taxes.</span> |
| Performance Table Not Relevant to Tax Deferred | <span style="color:#000000;font-family:Times New Roman;font-size:10pt;"> Actual after-tax returns depend on your tax situation </span><span style="color:#000000;font-family:Times New Roman;font-size:10pt;">and may differ from those shown. After-tax returns shown are not relevant if you are tax-exempt or if you hold your Fund shares through tax-advantaged arrangements (such as a 401(k) plan or individual retirement account). </span> |
| Performance Table One Class of after Tax Shown [Text] | <span style="color:#000000;font-family:Times New Roman;font-size:10pt;">After-tax returns are shown for Class VI </span><span style="color:#000000;font-family:Times New Roman;font-size:10pt;">shares only; after-tax returns for other classes will vary.</span> |
| Performance Availability Website Address [Text] | <span style="color:#000000;font-family:Times New Roman;font-size:10pt;">www.gmo.com</span> |
| Class VI | |
| Prospectus [Line Items] | |
| Year to Date Return, Label [Optional Text] | <span style="color:#000000;font-family:Times New Roman;font-size:10pt;">Year-to-Date:</span> |
| Bar Chart, Year to Date Return | 5.13% |
| Bar Chart, Year to Date Return, Date | Mar. 31, 2025 |
| Highest Quarterly Return, Label [Optional Text] | <span style="color:#000000;font-family:Times New Roman;font-size:10pt;">Highest Quarter:</span> |
| Highest Quarterly Return | 4.76% |
| Highest Quarterly Return, Date | Dec. 31, 2022 |
| Lowest Quarterly Return, Label [Optional Text] | <span style="color:#000000;font-family:Times New Roman;font-size:10pt;">Lowest Quarter:</span> |
| Lowest Quarterly Return | (6.99%) |
| Lowest Quarterly Return, Date | Mar. 31, 2020 |