v3.26.1
GMO Global Equity Allocation Fund Average Annual Total Returns
 12 Months Ended 23 Months Ended 52 Months Ended 54 Months Ended 60 Months Ended 120 Months Ended 337 Months Ended
Feb. 28, 2025
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
Dec. 31, 2024
MSCI ACWI (Fund benchmark) (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]   17.49% 16.42%          
Class III                
Prospectus [Line Items]                
Average Annual Return, Percent   9.51%       6.94% 6.99% 7.77%
Performance Inception Date Nov. 26, 1996              
Class III | After Taxes on Distributions                
Prospectus [Line Items]                
Average Annual Return, Percent   7.87%       5.15% 5.53% 5.86%
Class III | After Taxes on Distributions and Sales                
Prospectus [Line Items]                
Average Annual Return, Percent   6.32%       4.97% 5.26% 5.85%
Class III | MSCI ACWI + (Composite index)[Member]                
Prospectus [Line Items]                
Average Annual Return, Percent [2],[3]   17.49%       10.06% 9.23% 7.15%
Class III | MSCI ACWI (Fund benchmark) (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 [2]   17.49%       10.06% 9.23% 7.10%
Class R6                
Prospectus [Line Items]                
Average Annual Return, Percent   9.51%     9.55%  
Performance Inception Date Jul. 15, 2020              
Class R6 | MSCI ACWI + (Composite index)[Member]                
Prospectus [Line Items]                
Average Annual Return, Percent [2],[3]   17.49%     11.77%      
Class R6 | MSCI ACWI (Fund benchmark) (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 [2]   17.49%     11.77%      
Class I                
Prospectus [Line Items]                
Average Annual Return, Percent   9.39%   8.73%    
Performance Inception Date Aug. 17, 2020              
Class I | MSCI ACWI + (Composite index)[Member]                
Prospectus [Line Items]                
Average Annual Return, Percent [2],[3]   17.49%   11.00%        
Class I | MSCI ACWI (Fund benchmark) (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 [2]   17.49%   11.00%        
[1] 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.
[2] 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.
[3] The composite index provides a performance comparison that tracks changes in the Fund’s benchmark over time. See “Fund Benchmarks and Comparative Indices” for the time periods covered by each index included in the composite index.