v3.26.1
Average Annual Total Returns - Investment Trust Prospectus
 12 Months Ended 43 Months Ended 60 Months Ended 62 Months Ended 99 Months Ended 101 Months Ended 120 Months Ended
Aug. 01, 2026
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Bloomberg U.S. Aggregate Bond Index                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Bloomberg U.S. Aggregate Bond Index(reflects no deduction for fees, expenses or taxes)              
Average Annual Return, Percent   7.30%   (0.36%)       2.01%
Performance Inception Date Jul. 28, 2014              
ICE BofA U.S. High Yield Constrained Index                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] ICE BofA U.S. High Yield Constrained Index (Unhedged)(reflects no deduction for fees, expenses or taxes)              
Average Annual Return, Percent   8.50%   4.50%       6.44%
ICE BofA US High Yield Constrained Index (Unhedged)                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] ICE BofA US High Yield Constrained Index (Unhedged)(reflects no deduction for fees, expenses or taxes)              
Average Annual Return, Percent   8.50%   4.50%       6.44%
Bloomberg U.S. 1-3 Year Government/Credit Bond Index                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Bloomberg U.S. 1-3 Year Government/Credit Bond Index(reflects no deduction for fees, expenses or taxes)              
Average Annual Return, Percent   5.35%   1.97%       2.09%
Bloomberg U.S. Aggregate Bond Index (reflects no deduction for fees, expenses or taxes)                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Bloomberg U.S. Aggregate Bond Index(reflects no deduction for fees, expenses or taxes)              
Average Annual Return, Percent   7.30%   (0.36%)       2.01%
Bloomberg U.S. 1-5 Year Treasury Inflation Protected Securities (TIPS) Index                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Bloomberg U.S. 1-5 Year Treasury Inflation ProtectedSecurities (TIPS) Index  (reflects no deduction for fees, expenses or taxes)              
Average Annual Return, Percent   6.55%   3.32%       3.16%
Bloomberg U.S. 1-3 Year Government/Credit Bond Index (reflects no deduction for fees, expenses or taxes)                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Bloomberg U.S. 1-3 Year Government/Credit Bond Index   (reflects no deduction for fees, expenses or taxes)              
Average Annual Return, Percent   5.35%   1.97%       2.09%
Performance Inception Date Jul. 28, 2014              
CORE PLUS FUND, INVESTOR CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Investor Class Return Before Taxes              
Average Annual Return, Percent   7.42%   (0.28%)       2.17%
Performance Inception Date Nov. 30, 2006              
CORE PLUS FUND, INVESTOR CLASS | After Taxes on Distributions                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions              
Average Annual Return, Percent   5.35%   (1.87%)       0.74%
Performance Inception Date Nov. 30, 2006              
CORE PLUS FUND, INVESTOR CLASS | After Taxes on Distributions and Sales                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares              
Average Annual Return, Percent   4.35%   (0.89%)       1.04%
Performance Inception Date Nov. 30, 2006              
CORE PLUS FUND, I CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [1] I Class1 Return Before Taxes              
Average Annual Return, Percent [1]   7.52%   (0.18%)       2.28%
Performance Inception Date [1] Apr. 10, 2017              
CORE PLUS FUND, A CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] A Class Return Before Taxes              
Average Annual Return, Percent   2.33%   (1.44%)       1.44%
Performance Inception Date Nov. 30, 2006              
CORE PLUS FUND, C CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [2] C Class2 Return Before Taxes              
Average Annual Return, Percent [2]   6.36%   (1.27%)       1.31%
Performance Inception Date [2] Nov. 30, 2006              
CORE PLUS FUND, R CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R Class Return Before Taxes              
Average Annual Return, Percent   6.89%   (0.77%)       1.66%
Performance Inception Date Nov. 30, 2006              
CORE PLUS FUND, R5 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R5 Class Return Before Taxes              
Average Annual Return, Percent   7.63%   (0.06%)       2.38%
Performance Inception Date Nov. 30, 2006              
CORE PLUS FUND G CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] G Class Return Before Taxes              
Average Annual Return, Percent   8.01%   0.27% 0.59%      
Performance Inception Date Nov. 04, 2020              
DIVERSIFIED BOND FUND, I CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] I Class Return Before Taxes              
Average Annual Return, Percent   7.38%   (0.28%)       1.99%
Performance Inception Date Apr. 01, 1993              
DIVERSIFIED BOND FUND, I CLASS | After Taxes on Distributions                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions              
Average Annual Return, Percent   5.38%   (1.75%)       0.63%
Performance Inception Date Apr. 01, 1993              
DIVERSIFIED BOND FUND, I CLASS | After Taxes on Distributions and Sales                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares              
Average Annual Return, Percent   4.34%   (0.83%)       0.96%
Performance Inception Date Apr. 01, 1993              
DIVERSIFIED BOND FUND, INVESTOR CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Investor Class Return Before Taxes              
Average Annual Return, Percent   7.06%   (0.50%)       1.77%
Performance Inception Date Dec. 03, 2001              
DIVERSIFIED BOND FUND, Y CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [3] Y Class1 Return Before Taxes              
Average Annual Return, Percent [3]   7.30%   (0.25%)       2.02%
Performance Inception Date [3] Apr. 10, 2017              
DIVERSIFIED BOND FUND, A CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] A Class Return Before Taxes              
Average Annual Return, Percent   1.99%   (1.66%)       1.06%
Performance Inception Date Dec. 03, 2001              
DIVERSIFIED BOND FUND, C CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [4] C Class2 Return Before Taxes              
Average Annual Return, Percent [4]   6.11%   (1.47%)       0.91%
Performance Inception Date [4] Jan. 31, 2003              
DIVERSIFIED BOND FUND, R CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R Class Return Before Taxes              
Average Annual Return, Percent   6.53%   (0.99%)       1.27%
Performance Inception Date Jul. 29, 2005              
DIVERSIFIED BOND FUND, R5 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [5] R5 Class3 Return Before Taxes              
Average Annual Return, Percent [5]   7.28%   (0.28%)       1.99%
Performance Inception Date [5] Apr. 10, 2017              
DIVERSIFIED BOND FUND, R6 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R6 Class Return Before Taxes              
Average Annual Return, Percent   7.32%   (0.25%)       2.04%
Performance Inception Date Jul. 26, 2013              
DIVERSIFIED BOND FUND G CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] G Class Return Before Taxes              
Average Annual Return, Percent   7.68% 2.96%          
Performance Inception Date May 19, 2022              
HIGH INCOME FUND Y CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Y Class Return Before Taxes              
Average Annual Return, Percent   8.80%   4.71%       6.53%
Performance Inception Date Dec. 27, 2012              
HIGH INCOME FUND Y CLASS | After Taxes on Distributions                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions              
Average Annual Return, Percent   5.87%   2.01%       3.89%
Performance Inception Date Dec. 27, 2012              
HIGH INCOME FUND Y CLASS | After Taxes on Distributions and Sales                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares              
Average Annual Return, Percent   5.14%   2.39%       3.87%
Performance Inception Date Dec. 27, 2012              
HIGH INCOME FUND INVESTOR CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [6] Investor Class1 Return Before Taxes              
Average Annual Return, Percent [6]   8.58%   4.51%       6.33%
Performance Inception Date [6] Oct. 02, 2017              
HIGH INCOME FUND I CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [6] I Class1 Return Before Taxes              
Average Annual Return, Percent [6]   8.82%   4.63%       6.43%
Performance Inception Date [6] Oct. 02, 2017              
HIGH INCOME FUND A CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [6] A Class1 Return Before Taxes              
Average Annual Return, Percent [6]   3.44%   3.29%       5.58%
Performance Inception Date [6] Oct. 02, 2017              
HIGH INCOME FUND R5 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [6] R5 Class1 Return Before Taxes              
Average Annual Return, Percent [6]   8.80%   4.74%       6.54%
Performance Inception Date [6] Oct. 02, 2017              
HIGH INCOME FUND, R6 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R6 Class Return Before Taxes              
Average Annual Return, Percent   8.86%   4.76%   5.19%    
Performance Inception Date Oct. 02, 2017              
HIGH INCOME FUND G CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] G Class Return Before Taxes              
Average Annual Return, Percent   9.55% 8.81%          
Performance Inception Date May 19, 2022              
HIGH-YIELD FUND, INVESTOR CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Investor Class Return Before Taxes              
Average Annual Return, Percent   8.60%   3.23%       5.07%
Performance Inception Date Sep. 30, 1997              
HIGH-YIELD FUND, INVESTOR CLASS | After Taxes on Distributions                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions              
Average Annual Return, Percent   6.01%   1.10%       2.90%
Performance Inception Date Sep. 30, 1997              
HIGH-YIELD FUND, INVESTOR CLASS | After Taxes on Distributions and Sales                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares              
Average Annual Return, Percent   5.03%   1.51%       2.94%
Performance Inception Date Sep. 30, 1997              
HIGH-YIELD FUND, I CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [7] I Class1 Return Before Taxes              
Average Annual Return, Percent [7]   8.70%   3.34%       5.17%
Performance Inception Date [7] Apr. 10, 2017              
HIGH-YIELD FUND, Y CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [7] Y Class1 Return Before Taxes              
Average Annual Return, Percent [7]   8.81%   3.44%       5.28%
Performance Inception Date [7] Apr. 10, 2017              
HIGH-YIELD FUND, A CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] A Class Return Before Taxes              
Average Annual Return, Percent   3.45%   2.00%       4.31%
Performance Inception Date Mar. 08, 2002              
HIGH-YIELD FUND, C CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [8] C Class2 Return Before Taxes              
Average Annual Return, Percent [8]   7.52%   2.17%       4.17%
Performance Inception Date [8] Dec. 10, 2001              
HIGH-YIELD FUND, R CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R Class Return Before Taxes              
Average Annual Return, Percent   8.06%   2.72%       4.53%
Performance Inception Date Jul. 29, 2005              
HIGH-YIELD FUND, R5 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R5 Class Return Before Taxes              
Average Annual Return, Percent   8.81%   3.40%       5.26%
Performance Inception Date Aug. 02, 2004              
HIGH-YIELD FUND, R6 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R6 Class Return Before Taxes              
Average Annual Return, Percent   8.87%   3.45%       5.32%
Performance Inception Date Jul. 26, 2013              
MULTISECTOR INCOME FUND, INVESTOR CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Investor Class Return Before Taxes              
Average Annual Return, Percent   7.97%   2.22%       4.11%
Performance Inception Date Jul. 28, 2014              
MULTISECTOR INCOME FUND, INVESTOR CLASS | After Taxes on Distributions                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions              
Average Annual Return, Percent   5.55%   0.11%       2.29%
Performance Inception Date Jul. 28, 2014              
MULTISECTOR INCOME FUND, INVESTOR CLASS | After Taxes on Distributions and Sales                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares              
Average Annual Return, Percent   4.67%   0.76%       2.36%
Performance Inception Date Jul. 28, 2014              
MULTISECTOR INCOME FUND, I CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [9] I Class1 Return Before Taxes              
Average Annual Return, Percent [9]   8.07%   2.34%       4.21%
Performance Inception Date [9] Apr. 10, 2017              
MULTISECTOR INCOME FUND, Y CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [9] Y Class1 Return Before Taxes              
Average Annual Return, Percent [9]   8.17%   2.42%       4.31%
Performance Inception Date [9] Apr. 10, 2017              
MULTISECTOR INCOME FUND, A CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] A Class Return Before Taxes              
Average Annual Return, Percent   2.85%   1.03%       3.37%
Performance Inception Date Jul. 28, 2014              
MULTISECTOR INCOME FUND, C CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [10] C Class2 Return Before Taxes              
Average Annual Return, Percent [10]   6.90%   1.20%       3.22%
Performance Inception Date [10] Jul. 28, 2014              
MULTISECTOR INCOME FUND, R CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R Class Return Before Taxes              
Average Annual Return, Percent   7.43%   1.71%       3.59%
Performance Inception Date Jul. 28, 2014              
MULTISECTOR INCOME FUND, R5 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R5 Class Return Before Taxes              
Average Annual Return, Percent   8.18%   2.44%       4.31%
Performance Inception Date Jul. 28, 2014              
MULTISECTOR INCOME FUND, R6 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R6 Class Return Before Taxes              
Average Annual Return, Percent   8.24%   2.49%       4.37%
Performance Inception Date Jul. 28, 2014              
PRIME MONEY MARKET FUND, INVESTOR CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Investor Class              
Average Annual Return, Percent   3.96%   2.99%       1.93%
PRIME MONEY MARKET FUND, A CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] A Class              
Average Annual Return, Percent   3.70%   2.80%       1.77%
PRIME MONEY MARKET FUND, C CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [11] C Class1              
Average Annual Return, Percent [11]   3.19%   2.44%       1.56%
SHORT DURATION FUND, INVESTOR CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Investor Class Return Before Taxes              
Average Annual Return, Percent   5.62%   2.31%       2.41%
Performance Inception Date Nov. 30, 2006              
SHORT DURATION FUND, INVESTOR CLASS | After Taxes on Distributions                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions              
Average Annual Return, Percent   3.68%   0.90%       1.28%
Performance Inception Date Nov. 30, 2006              
SHORT DURATION FUND, INVESTOR CLASS | After Taxes on Distributions and Sales                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares              
Average Annual Return, Percent   3.30%   1.15%       1.35%
Performance Inception Date Nov. 30, 2006              
SHORT DURATION FUND, I CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [12] I Class1 Return Before Taxes              
Average Annual Return, Percent [12]   5.72%   2.43%       2.52%
Performance Inception Date [12] Apr. 10, 2017              
SHORT DURATION FUND, A CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] A Class Return Before Taxes              
Average Annual Return, Percent   2.98%   1.59%       1.91%
Performance Inception Date Nov. 30, 2006              
SHORT DURATION FUND, C CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [13] C Class2 Return Before Taxes              
Average Annual Return, Percent [13]   4.57%   1.29%       1.54%
Performance Inception Date [13] Nov. 30, 2006              
SHORT DURATION FUND, R CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R Class Return Before Taxes              
Average Annual Return, Percent   5.09%   1.80%       1.90%
Performance Inception Date Nov. 30, 2006              
SHORT DURATION FUND, R5 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R5 Class Return Before Taxes              
Average Annual Return, Percent   5.94%   2.53%       2.62%
Performance Inception Date Nov. 30, 2006              
SHORT DURATION FUND, R6 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R6 Class Return Before Taxes              
Average Annual Return, Percent   5.88%   2.56%     2.71%  
Performance Inception Date Jul. 28, 2017              
SHORT DURATION FUND, G CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] G Class Return Before Taxes              
Average Annual Return, Percent   6.20%   2.88% 2.98%      
Performance Inception Date Nov. 04, 2020              
SHORT DURATION INFLATION PROTECTION BOND FUND, INVESTOR CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Investor Class Return Before Taxes              
Average Annual Return, Percent   5.95%   3.20%       2.98%
Performance Inception Date May 31, 2005              
SHORT DURATION INFLATION PROTECTION BOND FUND, INVESTOR CLASS | After Taxes on Distributions                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions              
Average Annual Return, Percent   4.28%   1.70%       1.94%
Performance Inception Date May 31, 2005              
SHORT DURATION INFLATION PROTECTION BOND FUND, INVESTOR CLASS | After Taxes on Distributions and Sales                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares              
Average Annual Return, Percent   3.52%   1.81%       1.85%
Performance Inception Date May 31, 2005              
SHORT DURATION INFLATION PROTECTION BOND FUND, I CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [14] I Class1 Return Before Taxes              
Average Annual Return, Percent [14]   6.10%   3.31%       3.08%
Performance Inception Date [14] Apr. 10, 2017              
SHORT DURATION INFLATION PROTECTION BOND FUND, Y CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [14] Y Class1 Return Before Taxes              
Average Annual Return, Percent [14]   6.11%   3.41%       3.18%
Performance Inception Date [14] Apr. 10, 2017              
SHORT DURATION INFLATION PROTECTION BOND FUND, A CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] A Class Return Before Taxes              
Average Annual Return, Percent   3.38%   2.48%       2.49%
Performance Inception Date May 31, 2005              
SHORT DURATION INFLATION PROTECTION BOND FUND, C CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [15] C Class2 Return Before Taxes              
Average Annual Return, Percent [15]   4.97%   2.19%       2.12%
Performance Inception Date [15] May 31, 2005              
SHORT DURATION INFLATION PROTECTION BOND FUND, R CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R Class Return Before Taxes              
Average Annual Return, Percent   5.46%   2.69%       2.47%
Performance Inception Date May 31, 2005              
SHORT DURATION INFLATION PROTECTION BOND FUND, R5 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R5 Class Return Before Taxes              
Average Annual Return, Percent   6.11%   3.39%       3.18%
Performance Inception Date May 31, 2005              
SHORT DURATION INFLATION PROTECTION BOND FUND, R6 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R6 Class Return Before Taxes              
Average Annual Return, Percent   6.16%   3.45%       3.23%
Performance Inception Date Jul. 26, 2013              
SHORT DURATION INFLATION PROTECTION BOND FUND, G CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] G Class Return Before Taxes              
Average Annual Return, Percent   6.59%   3.78%     3.66%  
Performance Inception Date Jul. 28, 2017              
SHORT DURATION STRATEGIC INCOME FUND, INVESTOR CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Investor Class Return Before Taxes              
Average Annual Return, Percent   6.27%   2.66%       3.23%
Performance Inception Date Jul. 28, 2014              
SHORT DURATION STRATEGIC INCOME FUND, INVESTOR CLASS | After Taxes on Distributions                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions              
Average Annual Return, Percent   4.18%   0.91%       1.78%
Performance Inception Date Jul. 28, 2014              
SHORT DURATION STRATEGIC INCOME FUND, INVESTOR CLASS | After Taxes on Distributions and Sales                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Return After Taxes on Distributions and Sale of Fund Shares              
Average Annual Return, Percent   3.68%   1.26%       1.84%
Performance Inception Date Jul. 28, 2014              
SHORT DURATION STRATEGIC INCOME FUND, I CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [16] I Class1 Return Before Taxes              
Average Annual Return, Percent [16]   6.49%   2.76%       3.33%
Performance Inception Date [16] Apr. 10, 2017              
SHORT DURATION STRATEGIC INCOME FUND, Y CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [16] Y Class1 Return Before Taxes              
Average Annual Return, Percent [16]   6.48%   2.86%       3.43%
Performance Inception Date [16] Apr. 10, 2017              
SHORT DURATION STRATEGIC INCOME FUND, A CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] A Class Return Before Taxes              
Average Annual Return, Percent   3.62%   1.93%       2.74%
Performance Inception Date Jul. 28, 2014              
SHORT DURATION STRATEGIC INCOME FUND, C CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] [17] C Class2 Return Before Taxes              
Average Annual Return, Percent [17]   5.22%   1.64%       2.36%
Performance Inception Date [17] Jul. 28, 2014              
SHORT DURATION STRATEGIC INCOME FUND, R CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R Class Return Before Taxes              
Average Annual Return, Percent   5.86%   2.17%       2.73%
Performance Inception Date Jul. 28, 2014              
SHORT DURATION STRATEGIC INCOME FUND, R5 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R5 Class Return Before Taxes              
Average Annual Return, Percent   6.48%   2.84%       3.44%
Performance Inception Date Jul. 28, 2014              
SHORT DURATION STRATEGIC INCOME FUND, R6 CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] R6 Class Return Before Taxes              
Average Annual Return, Percent   6.53%   2.91%       3.49%
Performance Inception Date Jul. 28, 2014              
U.S. GOVERNMENT MONEY MARKET FUND, INVESTOR CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] Investor Class              
Average Annual Return, Percent   3.94%   2.94%       1.86%
Performance Inception Date Apr. 01, 1993              
U.S. GOVERNMENT MONEY MARKET FUND, A CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] A Class              
Average Annual Return, Percent   3.68%   2.75%       1.70%
Performance Inception Date Dec. 01, 2015              
U.S. GOVERNMENT MONEY MARKET FUND, C CLASS                
Prospectus [Line Items]                
Average Annual Return, Label [Optional Text] C Class              
Average Annual Return, Percent   3.16%   2.39%       1.50%
Performance Inception Date Dec. 01, 2015              
[1] Historical performance for the I Class prior to its inception is based on the performance of R5 Class shares. I Class performance has been adjusted to reflect differences in expenses between classes, if applicable.
[2] C Class shares automatically convert to A Class shares after approximately eight years. All returns for periods greater than eight years reflect this conversion.
[3] Historical performance for the Y Class prior to its inception is based on the performance of R6 Class shares. Y Class performance has been adjusted to reflect differences in expenses between classes. Since inception performance for the Y Class is based on the R6 Class inception date.
[4] C Class shares automatically convert to A Class shares after approximately eight years. All returns for periods greater than eight years reflect this conversion.
[5] Historical performance for the R5 Class prior to its inception is based on the performance of I Class shares, which have the same expenses as the R5 Class.
[6] Historical performance for the Investor, I, A and R5 Classes prior to their inception is based on the performance of the Predecessor Fund and Prior Predecessor Fund. Investor, I, A and R5 Class performance has been adjusted to reflect differences in sales charges, if applicable, and expenses between classes. Since inception performance is based on the inception date of the Predecessor Funds.
[7] Historical performance for the I and Y Classes prior to their inception is based on the performance of R5 Class shares. I and Y Class performance has been adjusted to reflect differences in expenses between classes, if applicable.
[8] C Class shares automatically convert to A Class shares after approximately eight years. All returns for periods greater than eight years reflect this conversion.
[9] Historical performance for the I and Y Classes prior to their inception is based on the performance of R5 Class shares. I and Y Class performance has been adjusted to reflect differences in expenses between classes, if applicable. Since inception performance for the I and Y Class is based on the R5 Class inception date.
[10] C Class shares automatically convert to A Class shares after approximately eight years. All returns for periods greater than eight years reflect this conversion.
[11] C Class shares automatically convert to A Class shares after approximately eight years. All returns for periods greater than eight years reflect this conversion.
[12] Historical performance for the I Class prior to its inception is based on the performance of R5 Class shares. I Class performance has been adjusted to reflect differences in expenses between classes, if applicable.
[13] C Class shares automatically convert to A Class shares after approximately eight years. All returns for periods greater than eight years reflect this conversion.
[14] Historical performance for the I and Y Classes prior to their inception is based on the performance of R5 Class shares. I and Y Class performance has been adjusted to reflect differences in expenses between classes, if applicable.
[15] C Class shares automatically convert to A Class shares after approximately eight years. All returns for periods greater than eight years reflect this conversion.
[16] Historical performance for the I and Y Classes prior to their inception is based on the performance of R5 Class shares. I and Y Class performance has been adjusted to reflect differences in expenses between classes, if applicable. Since inception performance for the I and Y Class is based on the R5 Class inception date.
[17] C Class shares automatically convert to A Class shares after approximately eight years. All returns for periods greater than eight years reflect this conversion.