v3.26.1
Shareholder Report, Average Annual Return (Details) 190987_Buffalo Growth - Income Fund_Investor Class_TSR Annual {Investor Class}
12 Months Ended 60 Months Ended 120 Months Ended
Mar. 31, 2026
Mar. 31, 2026
Mar. 31, 2026
Investor Class      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Buffalo Growth & Income Fund Investor Class    
Average Annual Return, Percent 9.54% 10.16% 12.22%
Russell 3000 Index [Member]      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Russell 3000 Index    
Average Annual Return, Percent 18.09% 10.87% 13.72%
Russell 1000 Index [Member]      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Russell 1000 Index    
Average Annual Return, Percent 17.74% 11.34% 13.97%