v3.26.1
S000001149 [Member] Average Annual Total Returns
 4 Months Ended 12 Months Ended 60 Months Ended 120 Months Ended 273 Months Ended 279 Months Ended
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Bloomberg U.S. Universal Bond Index            
Prospectus [Line Items]            
Average Annual Return, Percent [1]   7.58% 0.06% 2.44%    
Bloomberg U.S. Corporate High Yield Index –2% Issuer Cap            
Prospectus [Line Items]            
Average Annual Return, Percent [1]   8.62% 4.50% 6.52%    
CLASS I            
Prospectus [Line Items]            
Average Annual Return, Percent [1]   6.82% 3.05% 5.24%    
Performance Inception Date         Mar. 31, 2003  
CLASS M            
Prospectus [Line Items]            
Average Annual Return, Percent [1]   6.55% 2.79% 4.97%    
Performance Inception Date           Sep. 30, 2002
CLASS M | After Taxes on Distributions            
Prospectus [Line Items]            
Average Annual Return, Percent [1]   3.79% 0.49% 2.97%    
Performance Inception Date           Sep. 30, 2002
CLASS M | After Taxes on Distributions and Sales            
Prospectus [Line Items]            
Average Annual Return, Percent [1]   3.84% [2] 1.11% [2] 2.96%    
Performance Inception Date           Sep. 30, 2002
Class I-3            
Prospectus [Line Items]            
Performance Inception Date Aug. 25, 2025          
[1]
Class I-3 shares of the Fund have an inception date of August 25, 2025, and therefore do not have a full year of performance history as of the date of this Prospectus.
[2]
The “After Taxes on Distributions and Sale of Fund Shares” return is higher than the “After Taxes on Distributions” return because of realized losses that would have been sustained upon sale of Fund shares immediately after the relevant period.