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GMO U.S. Small Cap Value Fund Average Annual Total Returns - Class VI
12 Months Ended 60 Months Ended 66 Months Ended 120 Months Ended
Feb. 28, 2025
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
Prospectus [Line Items]          
Average Annual Return, Percent   11.16% 10.26% 10.94%
Performance Inception Date Jul. 02, 2019        
After Taxes on Distributions          
Prospectus [Line Items]          
Average Annual Return, Percent   10.75% 6.86% 7.78%
After Taxes on Distributions and Sales          
Prospectus [Line Items]          
Average Annual Return, Percent   6.94% 6.86% 7.54%
S&P SmallCap 600 Value Index (returns reflect no deduction for fees, expenses, or taxes)[Member]          
Prospectus [Line Items]          
Average Annual Return, Percent   7.56% 8.09% 9.23%  
S&P Composite 1500 Index (returns reflect no deduction for fees, expenses, or taxes)[Member]          
Prospectus [Line Items]          
Average Annual Return, Percent   23.95% 14.13% 14.65%