v3.26.1
S000021046 [Member] Annual Fund Operating Expenses - S000021046 [Member]
Feb. 28, 2026
Prospectus [Line Items]  
Fee Waiver or Reimbursement over Assets, Date of Termination June 30, 2027
C000159975 [Member]  
Prospectus [Line Items]  
Management Fees (as a percentage of Assets) 0.74%
Distribution and Service (12b-1) Fees 0.00%
Other Expenses (as a percentage of Assets): 0.09%
Expenses (as a percentage of Assets) 0.83% [1]
Fee Waiver or Reimbursement (0.01%) [2]
Net Expenses (as a percentage of Assets) 0.82%
C000159976 [Member]  
Prospectus [Line Items]  
Management Fees (as a percentage of Assets) 0.74%
Distribution and Service (12b-1) Fees 0.00%
Other Expenses (as a percentage of Assets): 0.04%
Expenses (as a percentage of Assets) 0.78% [1]
Fee Waiver or Reimbursement 0.00% [2]
Net Expenses (as a percentage of Assets) 0.78%
C000253709 [Member]  
Prospectus [Line Items]  
Management Fees (as a percentage of Assets) 0.74%
Distribution and Service (12b-1) Fees 0.00%
Other Expenses (as a percentage of Assets): 0.17%
Expenses (as a percentage of Assets) 0.91% [1]
Fee Waiver or Reimbursement 0.00% [2]
Net Expenses (as a percentage of Assets) 0.91%
C000059843 [Member]  
Prospectus [Line Items]  
Management Fees (as a percentage of Assets) 0.74%
Distribution and Service (12b-1) Fees 0.25%
Other Expenses (as a percentage of Assets): 0.17%
Expenses (as a percentage of Assets) 1.16% [1]
Fee Waiver or Reimbursement 0.00% [2]
Net Expenses (as a percentage of Assets) 1.16%
C000059844 [Member]  
Prospectus [Line Items]  
Management Fees (as a percentage of Assets) 0.74%
Distribution and Service (12b-1) Fees 1.00%
Other Expenses (as a percentage of Assets): 0.17%
Expenses (as a percentage of Assets) 1.91% [1]
Fee Waiver or Reimbursement 0.00% [2]
Net Expenses (as a percentage of Assets) 1.91%
C000059845 [Member]  
Prospectus [Line Items]  
Management Fees (as a percentage of Assets) 0.74%
Distribution and Service (12b-1) Fees 0.50%
Other Expenses (as a percentage of Assets): 0.17%
Expenses (as a percentage of Assets) 1.41% [1]
Fee Waiver or Reimbursement 0.00% [2]
Net Expenses (as a percentage of Assets) 1.41%
C000059846 [Member]  
Prospectus [Line Items]  
Management Fees (as a percentage of Assets) 0.74%
Distribution and Service (12b-1) Fees 0.00%
Other Expenses (as a percentage of Assets): 0.17%
Expenses (as a percentage of Assets) 0.91% [1]
Fee Waiver or Reimbursement 0.00% [2]
Net Expenses (as a percentage of Assets) 0.91%
[1] “Total annual Fund operating expenses” include acquired fund fees and expenses (expenses the Fund incurs indirectly through its investments in other investment companies) and may be higher than the ratio of expenses to average net assets shown in the Financial Highlights section of this prospectus because the ratio of expenses to average net assets does not include acquired fund fees and expenses.
[2] The Fund’s transfer agent has contractually agreed to waive fees and/or to reimburse expenses through June 30, 2027, unless sooner terminated by the Fund’s Board of Trustees (the Board), so that the fees payable under the Fund’s transfer agency agreement do not exceed the annual rate of 0.04% for Class Inst2.