v3.25.4
Average Annual Total Returns
 6 Months Ended 12 Months Ended 24 Months Ended 41 Months Ended 49 Months Ended 54 Months Ended 56 Months Ended 60 Months Ended 106 Months Ended 120 Months Ended
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
First Eagle Global Fund | Class A                      
Prospectus [Line Items]                      
Average Annual Return, Percent     24.99%           10.60%   9.48%
First Eagle Global Fund | Class A | After Taxes on Distributions                      
Prospectus [Line Items]                      
Average Annual Return, Percent     21.67%           8.99%   8.11%
First Eagle Global Fund | Class A | After Taxes on Distributions and Sales                      
Prospectus [Line Items]                      
Average Annual Return, Percent     15.89%           7.99%   7.33%
First Eagle Global Fund | Class C                      
Prospectus [Line Items]                      
Average Annual Return, Percent     29.59%           10.89%   9.21%
First Eagle Global Fund | Class I                      
Prospectus [Line Items]                      
Average Annual Return, Percent     31.89%           12.00%   10.32%
First Eagle Global Fund | Class R6                      
Prospectus [Line Items]                      
Average Annual Return, Percent     31.98%           12.08% 9.90%  
Performance Inception Date Mar. 01, 2017                    
First Eagle Global Fund | MSCI World Index (reflects no deduction for fees or expenses, but reflects net of withholding taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     21.09%           12.15% 12.30% 12.17%
First Eagle Overseas Fund | Class A                      
Prospectus [Line Items]                      
Average Annual Return, Percent     31.74%           8.28%   7.30%
First Eagle Overseas Fund | Class A | After Taxes on Distributions                      
Prospectus [Line Items]                      
Average Annual Return, Percent     28.10%           6.60%   6.12%
First Eagle Overseas Fund | Class A | After Taxes on Distributions and Sales                      
Prospectus [Line Items]                      
Average Annual Return, Percent     19.37%           5.97%   5.55%
First Eagle Overseas Fund | Class C                      
Prospectus [Line Items]                      
Average Annual Return, Percent     36.66%           8.60%   7.06%
First Eagle Overseas Fund | Class I                      
Prospectus [Line Items]                      
Average Annual Return, Percent     39.02%           9.69%   8.15%
First Eagle Overseas Fund | Class R6                      
Prospectus [Line Items]                      
Average Annual Return, Percent     39.15%           9.78% 8.05%  
Performance Inception Date Mar. 01, 2017                    
First Eagle Overseas Fund | MSCI EAFE Index (reflects no deduction for fees or expenses, but reflects net of withholding taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     31.22%           8.92% 8.66% 8.18%
First Eagle U.S. Fund | Class A                      
Prospectus [Line Items]                      
Average Annual Return, Percent     16.50%           11.52%   10.32%
First Eagle U.S. Fund | Class A | After Taxes on Distributions                      
Prospectus [Line Items]                      
Average Annual Return, Percent     13.68%           9.43%   8.25%
First Eagle U.S. Fund | Class A | After Taxes on Distributions and Sales                      
Prospectus [Line Items]                      
Average Annual Return, Percent     11.07%           8.70%   7.82%
First Eagle U.S. Fund | Class C                      
Prospectus [Line Items]                      
Average Annual Return, Percent     20.71%           11.82%   10.05%
First Eagle U.S. Fund | Class I                      
Prospectus [Line Items]                      
Average Annual Return, Percent     22.89%           12.96%   11.18%
First Eagle U.S. Fund | Class R6                      
Prospectus [Line Items]                      
Average Annual Return, Percent     22.98%           13.02% 10.42%  
Performance Inception Date Mar. 01, 2017                    
First Eagle U.S. Fund | S&P 500 Index (reflects no deduction for fees, expenses or taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     17.88%           14.42% 14.70% 14.82%
First Eagle Gold Fund | Class A                      
Prospectus [Line Items]                      
Average Annual Return, Percent     116.98%           18.39%   17.92%
First Eagle Gold Fund | Class A | After Taxes on Distributions                      
Prospectus [Line Items]                      
Average Annual Return, Percent     115.96%           17.84%   17.60%
First Eagle Gold Fund | Class A | After Taxes on Distributions and Sales                      
Prospectus [Line Items]                      
Average Annual Return, Percent     69.21%           14.69%   15.24%
First Eagle Gold Fund | Class C                      
Prospectus [Line Items]                      
Average Annual Return, Percent     125.68%           18.73%   17.63%
First Eagle Gold Fund | Class I                      
Prospectus [Line Items]                      
Average Annual Return, Percent     128.88%           19.90%   18.83%
First Eagle Gold Fund | Class R6                      
Prospectus [Line Items]                      
Average Annual Return, Percent     129.08%           20.02% 16.12%  
Performance Inception Date Mar. 01, 2017                    
First Eagle Gold Fund | MSCI World Index (reflects no deduction for fees or expenses, but reflects net of withholding taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     21.09%           12.15% 12.30% 12.17%
First Eagle Gold Fund | FTSE Gold Mines Index (reflects no deduction for fees, expenses or taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     169.34%           18.30% 15.44% 20.07%
First Eagle Global Income Builder Fund | Class A                      
Prospectus [Line Items]                      
Average Annual Return, Percent     19.90%           7.93%   7.41%
First Eagle Global Income Builder Fund | Class A | After Taxes on Distributions                      
Prospectus [Line Items]                      
Average Annual Return, Percent     18.11%           6.57%   6.31%
First Eagle Global Income Builder Fund | Class A | After Taxes on Distributions and Sales                      
Prospectus [Line Items]                      
Average Annual Return, Percent     12.01%           5.73%   5.55%
First Eagle Global Income Builder Fund | Class C                      
Prospectus [Line Items]                      
Average Annual Return, Percent     24.20%           8.18%   7.14%
First Eagle Global Income Builder Fund | Class I                      
Prospectus [Line Items]                      
Average Annual Return, Percent     26.46%           9.29%   8.22%
First Eagle Global Income Builder Fund | Class R6                      
Prospectus [Line Items]                      
Average Annual Return, Percent 7.74%   26.60%           9.37%    
First Eagle Global Income Builder Fund | MSCI World Index (reflects no deduction for fees or expenses, but reflects net of withholding taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent 12.30%   21.09%           12.15%   12.17%
First Eagle Global Income Builder Fund | Bloomberg U.S. Aggregate Bond Index (reflects no deduction for fees, expenses or taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent 1.87%   7.30%           (0.36%)   2.01%
First Eagle Global Income Builder Fund | Bloomberg Global Aggregate Bond Index (reflects no deduction for fees, expenses or taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent 1.01%   8.17%           (2.15%)   1.26%
First Eagle Global Income Builder Fund | 60% MSCI World Index/40% Bloomberg U.S. Aggregate Bond Index (reflects no deduction for fees or expenses, but reflects net of taxes)*                      
Prospectus [Line Items]                      
Average Annual Return, Percent [1] 8.26%   15.51%           7.13%   8.23%
First Eagle Global Income Builder Fund | 60% MSCI World Index/40% Bloomberg Global Aggregate Bond Index (reflects no deduction for fees or expenses, but reflects net of taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent 7.87%   15.90%           6.35%   7.89%
First Eagle Rising Dividend Fund | Class A                      
Prospectus [Line Items]                      
Average Annual Return, Percent     17.61%           9.82%   7.19%
First Eagle Rising Dividend Fund | Class A | After Taxes on Distributions                      
Prospectus [Line Items]                      
Average Annual Return, Percent     14.78%           7.72%   4.73%
First Eagle Rising Dividend Fund | Class A | After Taxes on Distributions and Sales                      
Prospectus [Line Items]                      
Average Annual Return, Percent     11.67%           7.24%   4.94%
First Eagle Rising Dividend Fund | Class C                      
Prospectus [Line Items]                      
Average Annual Return, Percent     21.92%           10.12%   6.94%
First Eagle Rising Dividend Fund | Class I                      
Prospectus [Line Items]                      
Average Annual Return, Percent     24.15%           11.23%   8.04%
First Eagle Rising Dividend Fund | Class R6                      
Prospectus [Line Items]                      
Average Annual Return, Percent     24.18%           11.24% 8.42%  
Performance Inception Date Mar. 01, 2017                    
First Eagle Rising Dividend Fund | S&P 500 Index (reflects no deduction for fees, expenses or taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     17.88%           14.42% 14.70% 14.82%
First Eagle Small Cap Opportunity Fund | Class A                      
Prospectus [Line Items]                      
Average Annual Return, Percent     7.42%       2.42%        
Performance Inception Date Jul. 01, 2021                    
First Eagle Small Cap Opportunity Fund | Class I                      
Prospectus [Line Items]                      
Average Annual Return, Percent     13.33%         4.37%      
Performance Inception Date Apr. 27, 2021                    
First Eagle Small Cap Opportunity Fund | Class I | After Taxes on Distributions                      
Prospectus [Line Items]                      
Average Annual Return, Percent     13.01%         4.01%      
First Eagle Small Cap Opportunity Fund | Class I | After Taxes on Distributions and Sales                      
Prospectus [Line Items]                      
Average Annual Return, Percent     8.05%         3.27%      
First Eagle Small Cap Opportunity Fund | Class R6                      
Prospectus [Line Items]                      
Average Annual Return, Percent     13.40%       3.88%        
Performance Inception Date Jul. 01, 2021                    
First Eagle Small Cap Opportunity Fund | S&P 500 Index (reflects no deduction for fees, expenses or taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     17.88%       12.54% 13.79%      
First Eagle Small Cap Opportunity Fund | Russell 2000® Value Index (reflects no deduction for fees or expenses, but reflects net of withholding taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     12.59%       4.28% 5.03%      
First Eagle Small Cap Opportunity Fund | Russell 2000® Index (reflects no deduction for fees or expenses, but reflects net of withholding taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     12.81%       3.02% 3.78%      
First Eagle U.S. Smid Cap Opportunity Fund | Class A                      
Prospectus [Line Items]                      
Average Annual Return, Percent     5.42%   5.97%            
Performance Inception Date Aug. 15, 2022                    
First Eagle U.S. Smid Cap Opportunity Fund | Class A | After Taxes on Distributions                      
Prospectus [Line Items]                      
Average Annual Return, Percent     5.37%   5.79%            
First Eagle U.S. Smid Cap Opportunity Fund | Class A | After Taxes on Distributions and Sales                      
Prospectus [Line Items]                      
Average Annual Return, Percent     3.21%   4.58%            
First Eagle U.S. Smid Cap Opportunity Fund | Class I                      
Prospectus [Line Items]                      
Average Annual Return, Percent     11.16%   7.88%            
Performance Inception Date Aug. 15, 2022                    
First Eagle U.S. Smid Cap Opportunity Fund | Class R6                      
Prospectus [Line Items]                      
Average Annual Return, Percent     11.17%   7.87%            
Performance Inception Date Aug. 15, 2022                    
First Eagle U.S. Smid Cap Opportunity Fund | S&P 500 Index (reflects no deduction for fees, expenses or taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     17.88%   16.53%            
First Eagle U.S. Smid Cap Opportunity Fund | Russell 2500TM Value Index (reflects no deduction for fees or expenses, but reflects net of withholding taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     12.73%   8.34%            
First Eagle U.S. Smid Cap Opportunity Fund | Russell 2500TM Index (reflects no deduction for fees or expenses, but reflects net of withholding taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     11.91%   8.43%            
First Eagle Global Real Assets Fund | Class A                      
Prospectus [Line Items]                      
Average Annual Return, Percent     19.28%     7.20%          
Performance Inception Date Nov. 30, 2021                    
First Eagle Global Real Assets Fund | Class A | After Taxes on Distributions                      
Prospectus [Line Items]                      
Average Annual Return, Percent     17.83%     6.44%          
First Eagle Global Real Assets Fund | Class A | After Taxes on Distributions and Sales                      
Prospectus [Line Items]                      
Average Annual Return, Percent     11.59%     5.36%          
First Eagle Global Real Assets Fund | Class I                      
Prospectus [Line Items]                      
Average Annual Return, Percent     25.89%     8.85%          
Performance Inception Date Nov. 30, 2021                    
First Eagle Global Real Assets Fund | Class R6                      
Prospectus [Line Items]                      
Average Annual Return, Percent     25.87%     8.83%          
Performance Inception Date Nov. 30, 2021                    
First Eagle Global Real Assets Fund | MSCI World Index (reflects no deduction for fees or expenses, but reflects net of withholding taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     21.09%     9.96%          
First Eagle Global Real Assets Fund | Consumer Price Index for Urban Consumers (CPI-U) (reflects no deduction for fees or expense)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     2.68%     3.87%          
First Eagle High Yield Municipal Fund | Class A                      
Prospectus [Line Items]                      
Average Annual Return, Percent     (3.55%)           1.68%   4.34%
First Eagle High Yield Municipal Fund | Class C                      
Prospectus [Line Items]                      
Average Annual Return, Percent     (2.65%)           1.85%   4.06%
First Eagle High Yield Municipal Fund | Class I                      
Prospectus [Line Items]                      
Average Annual Return, Percent     (0.72%)           2.87%   5.12%
First Eagle High Yield Municipal Fund | Class I | After Taxes on Distributions                      
Prospectus [Line Items]                      
Average Annual Return, Percent     (3.03%)           1.19%   3.14%
First Eagle High Yield Municipal Fund | Class I | After Taxes on Distributions and Sales                      
Prospectus [Line Items]                      
Average Annual Return, Percent     (0.43%)           1.69%   3.19%
First Eagle High Yield Municipal Fund | Class R6                      
Prospectus [Line Items]                      
Average Annual Return, Percent     (0.73%)           2.95% 3.77%  
Performance Inception Date Mar. 01, 2017                    
First Eagle High Yield Municipal Fund | S&P Municipal Yield Index (reflects no deduction for fees, expenses or taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     3.52%           1.94% 3.91% 4.03%
First Eagle High Yield Municipal Fund | S&P Municipal Bond Index (reflects no deduction for fees, expenses or taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent     4.26%           1.06% 2.53% 2.44%
First Eagle Short Duration High Yield Municipal Fund | Class A                      
Prospectus [Line Items]                      
Average Annual Return, Percent     (1.32%) 2.81%              
Performance Inception Date Jan. 02, 2024                    
First Eagle Short Duration High Yield Municipal Fund | Class A | After Taxes on Distributions                      
Prospectus [Line Items]                      
Average Annual Return, Percent     (3.21%) 1.77%              
First Eagle Short Duration High Yield Municipal Fund | Class A | After Taxes on Distributions and Sales                      
Prospectus [Line Items]                      
Average Annual Return, Percent     (0.79%) 2.19%              
First Eagle Short Duration High Yield Municipal Fund | Class C                      
Prospectus [Line Items]                      
Average Annual Return, Percent   (0.94%)                  
Performance Inception Date Jul. 11, 2025                    
First Eagle Short Duration High Yield Municipal Fund | Class I                      
Prospectus [Line Items]                      
Average Annual Return, Percent     1.52% 4.42%              
Performance Inception Date Jan. 02, 2024                    
First Eagle Short Duration High Yield Municipal Fund | Class R6                      
Prospectus [Line Items]                      
Average Annual Return, Percent     1.45% 4.43%              
Performance Inception Date Jan. 02, 2024                    
First Eagle Short Duration High Yield Municipal Fund | S&P Municipal Bond Index (reflects no deduction for fees, expenses or taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent   4.38% 4.26% 3.08%              
First Eagle Short Duration High Yield Municipal Fund | S&P Short Duration Municipal Yield Index (reflects no deduction for fees, expenses or taxes)                      
Prospectus [Line Items]                      
Average Annual Return, Percent   2.28% 4.29% 4.27%              
[1] Effective September 30, 2025, the Fund’s benchmark index changed from the composite index consisting of 60% of the MSCI World Index and 40% of the Bloomberg U.S. Aggregate Bond Index to the composite index consisting of 60% of the MSCI World Index and 40% of the Bloomberg Global Aggregate Bond Index. The Fund believes that the new index more closely reflects the Fund’s investment strategies.