v3.25.4
S000000586 [Member] Annual Fund Operating Expenses - BARON FIFTH AVENUE GROWTH FUND
Sep. 30, 2025
Prospectus [Line Items]  
Fee Waiver or Reimbursement over Assets, Date of Termination August 29, 2036
BARON FIFTH AVENUE GROWTH FUND  
Prospectus [Line Items]  
Management Fees (as a percentage of Assets) 0.70%
Distribution and Service (12b-1) Fees 0.25%
Other Expenses (as a percentage of Assets): 0.08%
Expenses (as a percentage of Assets) 1.03%
Fee Waiver or Reimbursement (0.03%)
Net Expenses (as a percentage of Assets) 1.00% [1]
Institutional Shares  
Prospectus [Line Items]  
Management Fees (as a percentage of Assets) 0.70%
Distribution and Service (12b-1) Fees 0.00%
Other Expenses (as a percentage of Assets): 0.06%
Expenses (as a percentage of Assets) 0.76%
Fee Waiver or Reimbursement (0.01%)
Net Expenses (as a percentage of Assets) 0.75% [1]
R6 Shares  
Prospectus [Line Items]  
Management Fees (as a percentage of Assets) 0.70%
Distribution and Service (12b-1) Fees 0.00%
Other Expenses (as a percentage of Assets): 0.06%
Expenses (as a percentage of Assets) 0.76%
Fee Waiver or Reimbursement (0.01%)
Net Expenses (as a percentage of Assets) 0.75% [1]
[1] BAMCO, Inc. (“BAMCO” or the “Adviser”) has agreed that, pursuant to a contract with an 11-year term terminating on August 29, 2036, it will reimburse certain expenses of the Fund, limiting net annual operating expenses (portfolio transaction costs, interest and dividend expense, acquired fund fees and expenses, fees and expenses related to filing foreign tax reclaims, and extraordinary expenses are not subject to the operating expense limitation) to 1.00% of average daily net assets of Retail Shares, 0.75% of average daily net assets of Institutional Shares and 0.75% of average daily net assets of R6 shares. Only the Board of Trustees of the Fund may terminate the expense reimbursement agreement prior to its termination date.