v3.26.3
Annual Total Returns
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
FAF Trust MM Prospectus Class A Member | Government Obligations Fund | Government Obligations Fund Class A                    
Prospectus [Line Items]                    
Annual Return [Percent] [1] 3.60% 4.57% 4.39% 1.09% 0.01% 0.18% 1.50% 1.12% 0.21% 0.01%
FAF Trust MM Prospectus Class A Member | Retail Prime Obligations Fund | Retail Prime Obligations Fund Class A                    
Prospectus [Line Items]                    
Annual Return [Percent] [2] 3.69% 4.69% 4.58% 1.23% 0.01% 0.28% 1.84% 1.41% 0.46%  
FAF Trust MM Prospectus Class A Member | Retail Tax Free Obligations Fund | Retail Tax Free Obligations Fund Class A                    
Prospectus [Line Items]                    
Annual Return [Percent] [3] 2.04% 2.68% 2.61% 0.59% 0.01% 0.23% 0.75% 0.68% 0.12% 0.01%
FAF Trust MM Prospectus Class A Member | Treasury Obligations Fund | Treasury Obligations Fund Class A                    
Prospectus [Line Items]                    
Annual Return [Percent] [4] 3.59% 4.63% 4.42% 1.13% 0.01% 0.18% 1.49% 1.13% 0.21% none
FAF Trust MM Prospectus Class A Member | U.S. Treasury Money Market Fund | U.S. Treasury Money Market Fund Class A                    
Prospectus [Line Items]                    
Annual Return [Percent] [5] 3.54% 4.55% 4.33% 1.02% none 0.17% 1.44% 1.11% 0.17% none
FAF Trust MM Prospectus Class D Member | Government Obligations Fund | Government Obligations Fund Class D                    
Prospectus [Line Items]                    
Annual Return [Percent] [6] 3.76% 4.72% 4.54% 1.18% 0.01% 0.21% 1.65% 1.28% 0.33% 0.01%
FAF Trust MM Prospectus Class D Member | Treasury Obligations Fund | Treasury Obligations Fund Class D                    
Prospectus [Line Items]                    
Annual Return [Percent] [7] 3.75% 4.70% 4.58% 1.23% 0.01% 0.21% 1.64% 1.29% 0.33% none
FAF Trust MM Prospectus Class D Member | U.S. Treasury Money Market Fund | U.S. Treasury Money Market Fund Class D                    
Prospectus [Line Items]                    
Annual Return [Percent] [8] 3.70% 4.70% 4.49% 1.11% none 0.21% 1.59% 1.26% 0.29% none
FAF Trust MM Prospectus Class P Member | Government Obligations Fund | Government Obligations Fund Class P                    
Prospectus [Line Items]                    
Annual Return [Percent] [9] 4.22% 5.18% 5.00% 1.51% 0.03% 0.38% 2.11% 1.73%    
FAF Trust MM Prospectus Class P Member | Treasury Obligations Fund | Treasury Obligations Fund Class P                    
Prospectus [Line Items]                    
Annual Return [Percent] [10] 4.20% 5.15% 5.05% 1.57% 0.02% 0.37% 2.10% 1.74%    
FAF Trust MM Prospectus Class T Member | Government Obligations Fund | Government Obligations Fund Class T                    
Prospectus [Line Items]                    
Annual Return [Percent] [11] 3.96% 4.92% 4.75% 1.31% 0.01%          
FAF Trust MM Prospectus Class T Member | Retail Prime Obligations Fund | Retail Prime Obligations Fund Class T                    
Prospectus [Line Items]                    
Annual Return [Percent] [12] 4.05% 5.05% 4.94% 1.47% 0.01% 0.36% 2.01% 1.73% 0.80%  
FAF Trust MM Prospectus Class T Member | Retail Tax Free Obligations Fund | Retail Tax Free Obligations Fund Class T                    
Prospectus [Line Items]                    
Annual Return [Percent] [13] 2.41% 3.04% 2.97% 0.82% 0.01%          
FAF Trust MM Prospectus Class T Member | Treasury Obligations Fund | Treasury Obligations Fund Class T                    
Prospectus [Line Items]                    
Annual Return [Percent] [14] 3.95% 4.91% 4.79% 1.37% 0.01%          
FAF Trust MM Prospectus Class T Member | U.S. Treasury Money Market Fund | U.S. Treasury Money Market Fund Class T                    
Prospectus [Line Items]                    
Annual Return [Percent] [15] 3.90% 4.91% 4.69% 1.25% none          
FAF Trust MM Prospectus Class T Member | Institutional Prime Obligations Fund | Institutional Prime Obligations Fund Class T                    
Prospectus [Line Items]                    
Annual Return [Percent] [16] 3.98% 5.04% 4.93% 1.47% none 0.34% 2.02% 1.70% 0.77% 0.10%
FAF Trust MM Prospectus Class U Member | Government Obligations Fund | Government Obligations Fund Class U                    
Prospectus [Line Items]                    
Annual Return [Percent] [17] 4.25% 5.21% 5.04% 1.53% 0.03% 0.41% 2.14%      
FAF Trust MM Prospectus Class V Member | Government Obligations Fund | Government Obligations Fund Class V                    
Prospectus [Line Items]                    
Annual Return [Percent] [18] 4.07% 5.03% 4.86% 1.38% 0.01% 0.30% 1.96% 1.58% 0.63% 0.11%
FAF Trust MM Prospectus Class V Member | Retail Prime Obligations Fund | Retail Prime Obligations Fund Class V                    
Prospectus [Line Items]                    
Annual Return [Percent] [19] 4.15% 5.16% 5.04% 1.55% 0.01% 0.42% 2.12% 1.83% 0.91%  
FAF Trust MM Prospectus Class V Member | Retail Tax Free Obligations Fund | Retail Tax Free Obligations Fund Class V                    
Prospectus [Line Items]                    
Annual Return [Percent] [20] 2.50% 3.14% 3.07% 0.90% 0.01% 0.38% 1.20% 1.14% 0.56% 0.18%
FAF Trust MM Prospectus Class V Member | Treasury Obligations Fund | Treasury Obligations Fund Class V                    
Prospectus [Line Items]                    
Annual Return [Percent] [21] 4.06% 5.01% 4.89% 1.44% 0.01% 0.28% 1.95% 1.59% 0.63% 0.09%
FAF Trust MM Prospectus Class V Member | U.S. Treasury Money Market Fund | U.S. Treasury Money Market Fund Class V                    
Prospectus [Line Items]                    
Annual Return [Percent] [22] 4.01% 5.02% 4.80% 1.33% none 0.29% 1.90% 1.57% 0.58% 0.04%
FAF Trust MM Prospectus Class V Member | Institutional Prime Obligations Fund | Institutional Prime Obligations Fund Class V                    
Prospectus [Line Items]                    
Annual Return [Percent] [23] 4.09% 5.13% 5.03% 1.56% none 0.39% 2.12% 1.81% 0.86% 0.19%
FAF Trust MM Prospectus Class X Member | Government Obligations Fund | Government Obligations Fund Class X                    
Prospectus [Line Items]                    
Annual Return [Percent] [24] 4.23% 5.19% 5.02% 1.52% 0.03% 0.40% 2.12% 1.74% 0.79%  
FAF Trust MM Prospectus Class X Member | Retail Prime Obligations Fund | Retail Prime Obligations Fund Class X                    
Prospectus [Line Items]                    
Annual Return [Percent] [25] 4.32% 5.33% 5.21% 1.68% 0.02% 0.55% 2.28% 1.99% 1.07%  
FAF Trust MM Prospectus Class X Member | Treasury Obligations Fund | Treasury Obligations Fund Class X                    
Prospectus [Line Items]                    
Annual Return [Percent] [26] 4.22% 5.17% 5.06% 1.57% 0.02% 0.38% 2.11% 1.75% 0.79%  
FAF Trust MM Prospectus Class X Member | U.S. Treasury Money Market Fund | U.S. Treasury Money Market Fund Class X                    
Prospectus [Line Items]                    
Annual Return [Percent] [27] 3.54% 4.55% 4.33% 1.02% none 0.17% 1.44% 1.11% 0.17% none
FAF Trust MM Prospectus Class Y Member | Government Obligations Fund | Government Obligations Fund Class Y                    
Prospectus [Line Items]                    
Annual Return [Percent] [28] 3.91% 4.87% 4.70% 1.28% 0.01% 0.25% 1.81% 1.43% 0.48% 0.01%
FAF Trust MM Prospectus Class Y Member | Retail Prime Obligations Fund | Retail Prime Obligations Fund Class Y                    
Prospectus [Line Items]                    
Annual Return [Percent] [29] 4.00% 5.00% 4.89% 1.43% 0.01% 0.34% 1.96% 1.67% 0.76%  
FAF Trust MM Prospectus Class Y Member | Retail Tax Free Obligations Fund | Retail Tax Free Obligations Fund Class Y                    
Prospectus [Line Items]                    
Annual Return [Percent] [30] 2.35% 2.99% 2.92% 0.78% 0.01% 0.32% 0.32% 1.05% 0.98% 0.41%
FAF Trust MM Prospectus Class Y Member | Treasury Obligations Fund | Treasury Obligations Fund Class Y                    
Prospectus [Line Items]                    
Annual Return [Percent] [31] 3.90% 4.85% 4.74% 1.33% 0.01% 0.24% 1.80% 1.44% 0.48% 0.01%
FAF Trust MM Prospectus Class Y Member | U.S. Treasury Money Market Fund | U.S. Treasury Money Market Fund Class Y                    
Prospectus [Line Items]                    
Annual Return [Percent] [32] 3.86% 4.86% 4.64% 1.22% none 0.25% 1.75% 1.42% 0.43% none
FAF Trust MM Prospectus Class Y Member | Institutional Prime Obligations Fund | Institutional Prime Obligations Fund Class Y                    
Prospectus [Line Items]                    
Annual Return [Percent] [33] 3.94% 4.97% 4.88% 1.44% none 0.31% 1.97% 1.65% 0.72% 0.06%
FAF Trust MM Prospectus Class Z Member | Government Obligations Fund | Government Obligations Fund Class Z                    
Prospectus [Line Items]                    
Annual Return [Percent] [34] 4.19% 5.15% 4.98% 1.48% 0.02% 0.37% 2.08% 1.70% 0.75% 0.23%
FAF Trust MM Prospectus Class Z Member | Retail Prime Obligations Fund | Retail Prime Obligations Fund Class Z                    
Prospectus [Line Items]                    
Annual Return [Percent] [35] 4.26% 5.26% 5.15% 1.63% 0.01% 0.49% 2.22% 1.93% 1.01%  
FAF Trust MM Prospectus Class Z Member | Retail Tax Free Obligations Fund | Retail Tax Free Obligations Fund Class Z                    
Prospectus [Line Items]                    
Annual Return [Percent] [36] 2.60% 3.24% 3.17% 0.98% 0.01% 0.44% 1.30% 1.24% 0.66% 0.26%
FAF Trust MM Prospectus Class Z Member | Treasury Obligations Fund | Treasury Obligations Fund Class Z                    
Prospectus [Line Items]                    
Annual Return [Percent] [37] 4.17% 5.13% 5.02% 1.54% 0.02% 0.35% 2.07% 1.71% 0.75% 0.20%
FAF Trust MM Prospectus Class Z Member | U.S. Treasury Money Market Fund | U.S. Treasury Money Market Fund Class Z                    
Prospectus [Line Items]                    
Annual Return [Percent] [38] 4.11% 5.12% 4.90% 1.41% 0.01% 0.35% 2.00% 1.67% 0.68% 0.13%
FAF Trust MM Prospectus Class Z Member | Institutional Prime Obligations Fund | Institutional Prime Obligations Fund Class Z                    
Prospectus [Line Items]                    
Annual Return [Percent] [39] 4.19% 5.25% 5.13% 1.64% 0.05% 0.50% 2.28% 1.97% 0.98% 0.29%
[1] Total return for the period 1/1/2026 through 9/30/2026 was 2.25%.
[2] Total return for the period 1/1/2026 through 9/30/2026 was 2.32%.
[3] Total return for the period 1/1/2026 through 9/30/2026 was 1.24%.
[4] Total return for the period 1/1/2026 through 9/30/2026 was 2.26%.
[5] Total return for the period 1/1/2026 through 9/30/2026 was 2.25%.
[6] Total return for the period 1/1/2026 through 9/30/2026 was 2.37%.
[7] Total return for the period 1/1/2026 through 9/30/2026 was 2.37%.
[8] Total return for the period 1/1/2026 through 9/30/2026 was 2.37%.
[9] Total return for the period 1/1/2026 through 9/30/2026 was 2.71%.
[10] Total return for the period 1/1/2026 through 9/30/2026 was 2.70%.
[11] Total return for the period 1/1/2026 through 9/30/2026 was 2.52%.
[12] Total return for the period 1/1/2026 through 9/30/2026 was 2.59%.
[13] Total return for the period 1/1/2026 through 9/30/2026 was 1.51%.
[14] Total return for the period 1/1/2026 through 9/30/2026 was 2.53%.
[15] Total return for the period 1/1/2026 through 9/30/2026 was 2.52%.
[16] Total return for the period 1/1/2026 through 9/30/2026 was 2.51%.
[17] Total return for the period 1/1/2026 through 9/30/2026 was 2.73%.
[18] Total return for the period 1/1/2026 through 9/30/2026 was 2.59%.
[19] Total return for the period 1/1/2026 through 9/30/2026 was 2.66%.
[20] Total return for the period 1/1/2026 through 9/30/2026 was 1.58%.
[21] Total return for the period 1/1/2026 through 9/30/2026 was 2.60%.
[22] Total return for the period 1/1/2026 through 9/30/2026 was 2.60%.
[23] Total return for the period 1/1/2026 through 9/30/2026 was 2.59%.
[24] Total return for the period 1/1/2026 through 9/30/2026 was 2.71%.
[25] Total return for the period 1/1/2026 through 9/30/2026 was 2.79%.
[26] Total return for the period 1/1/2026 through 9/30/2026 was 2.72%.
[27] Total return for the period 1/1/2026 through 9/30/2026 was 2.25%.
[28] Total return for the period 1/1/2026 through 9/30/2026 was 2.48%.
[29] Total return for the period 1/1/2026 through 9/30/2026 was 2.55%.
[30] Total return for the period 1/1/2026 through 9/30/2026 was 1.47%.
[31] Total return for the period 1/1/2026 through 9/30/2026 was 2.49%.
[32] Total return for the period 1/1/2026 through 9/30/2026 was 2.48%.
[33] Total return for the period 1/1/2026 through 9/30/2026 was 2.48%.
[34] Total return for the period 1/1/2026 through 9/30/2026 was 2.68%.
[35] Total return for the period 1/1/2026 through 9/30/2026 was 2.74%.
[36] Total return for the period 1/1/2026 through 9/30/2026 was 1.66%.
[37] Total return for the period 1/1/2026 through 9/30/2026 was 2.69%.
[38] Total return for the period 1/1/2026 through 9/30/2026 was 2.67%.
[39] Total return for the period 1/1/2026 through 9/30/2026 was 2.67%.