GMO U.S. Treasury Fund Average Annual Total Returns - Class VI |
12 Months Ended | 60 Months Ended | 120 Months Ended | 201 Months Ended | |
|---|---|---|---|---|---|
Feb. 28, 2026 |
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
|
| Prospectus [Line Items] | |||||
| Average Annual Return, Percent | 4.44% | 3.17% | 2.26% | 1.39% | |
| Performance Inception Date | Mar. 17, 2009 | ||||
| After Taxes on Distributions | |||||
| Prospectus [Line Items] | |||||
| Average Annual Return, Percent | 2.69% | 1.82% | 1.33% | 0.82% | |
| After Taxes on Distributions and Sales | |||||
| Prospectus [Line Items] | |||||
| Average Annual Return, Percent | 2.61% | 1.84% | 1.33% | 0.82% | |
| FTSE 3-Month Treasury Bill Index (returns reflect no deduction for fees, expenses, or taxes)[Member] | |||||
| Prospectus [Line Items] | |||||
| Average Annual Return, Percent | 4.40% | 3.31% | 2.23% | 1.35% | |
| Bloomberg U.S. Aggregate Index (reflects no deduction for fees, expenses, or taxes)[Member] | |||||
| Prospectus [Line Items] | |||||
| Average Annual Return, Percent | 7.30% | (0.36%) | 2.01% | 2.98% |