v3.26.1
GMO International Equity Fund Average Annual Total Returns
 12 Months Ended 55 Months Ended 60 Months Ended 120 Months Ended 336 Months Ended 465 Months Ended
Feb. 28, 2026
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Class III              
Prospectus [Line Items]              
Average Annual Return, Percent [1]   44.00%   14.51% 10.34%   8.14%
Performance Inception Date Mar. 31, 1987            
Class III | After Taxes on Distributions              
Prospectus [Line Items]              
Average Annual Return, Percent [1]   41.55%   12.86% 9.15%   6.73%
Class III | After Taxes on Distributions and Sales              
Prospectus [Line Items]              
Average Annual Return, Percent [1]   26.76%   11.10% 8.13%   6.49%
Class III | MSCI World ex USA Index (returns reflect no deduction for fees or expenses, but are net of withholding tax on dividend reinvestments)[Member]              
Prospectus [Line Items]              
Average Annual Return, Percent [1],[2],[3]   31.85%   9.47% 8.55%   5.95%
Class III | MSCI EAFE Index (returns reflect no deduction for fees or expenses, but are net of withholding tax on dividend reinvestments)[Member]              
Prospectus [Line Items]              
Average Annual Return, Percent [1],[2],[3]   31.22%   8.93% 8.18%   5.82%
Class IV              
Prospectus [Line Items]              
Average Annual Return, Percent [1]   44.13%   14.58% 10.41% 7.64%  
Performance Inception Date Jan. 09, 1998            
Class IV | MSCI World ex USA Index (returns reflect no deduction for fees or expenses, but are net of withholding tax on dividend reinvestments)[Member]              
Prospectus [Line Items]              
Average Annual Return, Percent [1],[2],[3]   31.85%   9.47% 8.55% 5.81%  
Class IV | MSCI EAFE Index (returns reflect no deduction for fees or expenses, but are net of withholding tax on dividend reinvestments)[Member]              
Prospectus [Line Items]              
Average Annual Return, Percent [1],[2],[3]   31.22%   8.93% 8.18% 5.90%  
Class I              
Prospectus [Line Items]              
Average Annual Return, Percent [1]   43.78% 12.16%    
Performance Inception Date May 24, 2021            
Class I | MSCI World ex USA Index (returns reflect no deduction for fees or expenses, but are net of withholding tax on dividend reinvestments)[Member]              
Prospectus [Line Items]              
Average Annual Return, Percent [1],[2],[3]   31.85% 7.95%        
Class I | MSCI EAFE Index (returns reflect no deduction for fees or expenses, but are net of withholding tax on dividend reinvestments)[Member]              
Prospectus [Line Items]              
Average Annual Return, Percent [1],[2],[3]   31.22% 7.57%        
[1] Returns include a substantial, one-time litigation settlement recovery received on December 16, 2024. This event contributed 5.25% to 2024 annual performance.
[2] Effective June 20, 2026, the Fund changed its benchmark from the MSCI EAFE Index to the MSCI World ex USA Index because GMO believes that the MSCI World ex USA Index is more appropriate in light of the Fund's investment strategy.
[3] MSCI data may not be reproduced or used for any other purpose. MSCI provides no warranties, has not prepared or approved this report, and has no liability hereunder.