v3.25.4
S000042178 [Member] Average Annual Total Returns
 12 Months Ended 60 Months Ended 112 Months Ended 120 Months Ended 147 Months Ended
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Russell 2000® Growth Index (reflects no deduction for fees, expenses or taxes)          
Prospectus [Line Items]          
Average Annual Return, Percent 13.01% 3.18% 8.80% 9.57%  
Russell 3000® Index (reflects no deduction for fees, expenses or taxes)          
Prospectus [Line Items]          
Average Annual Return, Percent 17.15% 13.15% 13.53% 14.29%  
BARON DISCOVERY FUND          
Prospectus [Line Items]          
Average Annual Return, Percent 10.69% 1.22%   13.91% 12.33%
Performance Inception Date         Sep. 30, 2013
BARON DISCOVERY FUND | After Taxes on Distributions          
Prospectus [Line Items]          
Average Annual Return, Percent 10.69% 0.97%   13.42% 11.93%
Performance Inception Date         Sep. 30, 2013
BARON DISCOVERY FUND | After Taxes on Distributions and Sales          
Prospectus [Line Items]          
Average Annual Return, Percent 6.33% 0.86%   11.57% 10.36%
Performance Inception Date         Sep. 30, 2013
Institutional Shares          
Prospectus [Line Items]          
Average Annual Return, Percent 10.96% 1.48%   14.20% 12.61%
Performance Inception Date         Sep. 30, 2013
R6 Shares          
Prospectus [Line Items]          
Average Annual Return, Percent [1] 10.96% 1.48% 12.61% 14.21%  
Performance Inception Date [1]     Aug. 31, 2016    
[1] Performance for the R6 Shares prior to August 31, 2016 is based on the performance of the Institutional Shares.