v3.26.1
GMO Resources Fund Average Annual Total Returns
 12 Months Ended 23 Months Ended 35 Months Ended 47 Months Ended 60 Months Ended 120 Months Ended 141 Months Ended 156 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
Dec. 31, 2024
MSCI ACWI Commodity Producers 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]   (12.77%) (7.32%)            
MSCI ACWI (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   (17.70%)       3.99% 7.00%   4.98%
Performance Inception Date Dec. 28, 2011                
Class III | After Taxes on Distributions                  
Prospectus [Line Items]                  
Average Annual Return, Percent   (18.38%)       1.90% 5.52%   3.47%
Class III | After Taxes on Distributions and Sales                  
Prospectus [Line Items]                  
Average Annual Return, Percent   (10.05%)       2.82% 5.43%   3.68%
Class III | MSCI ACWI Commodity Producers 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 [2]   (5.56%)       5.89% 4.02%   2.34%
Class III | MSCI ACWI (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%   10.42%
Class IV                  
Prospectus [Line Items]                  
Average Annual Return, Percent   (17.64%)       4.04% 7.05% 4.77%  
Performance Inception Date Mar. 20, 2013                
Class IV | MSCI ACWI Commodity Producers 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 [2]   (5.56%)       5.89% 4.02% 2.42%  
Class IV | MSCI ACWI (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% 9.49%  
Class VI                  
Prospectus [Line Items]                  
Average Annual Return, Percent   (17.60%)   (8.72%)      
Performance Inception Date Feb. 08, 2022                
Class VI | MSCI ACWI Commodity Producers 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 [2]   (5.56%)   1.65%          
Class VI | MSCI ACWI (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%   7.26%          
Class R6                  
Prospectus [Line Items]                  
Average Annual Return, Percent   (17.73%)     (2.51%)    
Performance Inception Date Jan. 22, 2021                
Class R6 | MSCI ACWI Commodity Producers 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 [2]   (5.56%)     9.46%        
Class R6 | MSCI ACWI (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%     7.84%        
Class I                  
Prospectus [Line Items]                  
Average Annual Return, Percent   (17.83%)     (2.61%)    
Performance Inception Date Jan. 22, 2021                
Class I | MSCI ACWI Commodity Producers 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 [2]   (5.56%)     9.46%        
Class I | MSCI ACWI (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%     7.84%        
[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.