v3.26.1
Shareholder Report, Line Graph (Details) 190987_Buffalo Growth - Income Fund_Institutional Class_TSR Annual {Institutional Class} - USD ($)
12 Months Ended
Mar. 31, 2025
Mar. 31, 2024
Mar. 31, 2023
Mar. 31, 2022
Mar. 31, 2021
Mar. 31, 2020
Jul. 01, 2019
Mar. 31, 2026
Institutional Class                
Account Value [Line Items]                
Line Graph and Table Measure Name               Buffalo Growth & Income Fund Institutional Class
Accumulated Value $ 504,477 $ 470,167 $ 368,858 $ 384,384 $ 338,620 $ 219,149 $ 250,000 $ 553,317
Russell 3000 Index [Member]                
Account Value [Line Items]                
Line Graph and Table Measure Name               Russell 3000 Index
Accumulated Value 499,505 465,873 360,323 394,141 352,149 216,670 250,000 $ 589,843
Russell 1000 Index [Member]                
Account Value [Line Items]                
Line Graph and Table Measure Name               Russell 1000 Index
Accumulated Value $ 510,713 $ 473,668 $ 364,731 $ 398,149 $ 351,505 $ 218,887 $ 250,000 $ 601,336