v3.26.1
Shareholder Report, Line Graph (Details) 190996_Buffalo Growth 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 Fund Institutional Class
Accumulated Value $ 466,719 $ 449,470 $ 330,094 $ 376,985 $ 343,529 $ 222,691 $ 250,000 $ 510,238
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 3000 Growth Index [Member]                
Account Value [Line Items]                
Line Graph and Table Measure Name               Russell 3000 Growth Index
Accumulated Value $ 576,853 $ 538,186 $ 390,121 $ 437,754 $ 387,877 $ 236,058 $ 250,000 $ 684,989