v3.26.1
Expense Example
Jul. 29, 2026
USD ($)
Buffalo Blue Chip Growth Fund | Buffalo Blue Chip Growth Fund Investor Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year $ 93
Expense Example, with Redemption, 3 Years 290
Expense Example, with Redemption, 5 Years 504
Expense Example, with Redemption, 10 Years 1,120
Buffalo Blue Chip Growth Fund | Buffalo Blue Chip Growth Fund Institutional Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 80
Expense Example, with Redemption, 3 Years 249
Expense Example, with Redemption, 5 Years 433
Expense Example, with Redemption, 10 Years 966
Buffalo Early Stage Growth Fund | Buffalo Early Stage Growth Fund Investor Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 151
Expense Example, with Redemption, 3 Years 468
Expense Example, with Redemption, 5 Years 808
Expense Example, with Redemption, 10 Years 1,768
Buffalo Early Stage Growth Fund | Buffalo Early Stage Growth Fund Institutional Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 137
Expense Example, with Redemption, 3 Years 428
Expense Example, with Redemption, 5 Years 739
Expense Example, with Redemption, 10 Years 1,624
Buffalo Flexible Allocation Fund | Buffalo Flexible Allocation Fund Investor Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 102
Expense Example, with Redemption, 3 Years 318
Expense Example, with Redemption, 5 Years 552
Expense Example, with Redemption, 10 Years 1,225
Buffalo Flexible Allocation Fund | Buffalo Flexible Allocation Fund Institutional Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 88
Expense Example, with Redemption, 3 Years 274
Expense Example, with Redemption, 5 Years 477
Expense Example, with Redemption, 10 Years 1,061
Buffalo Growth Fund | Buffalo Growth Fund Investor Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 92
Expense Example, with Redemption, 3 Years 287
Expense Example, with Redemption, 5 Years 498
Expense Example, with Redemption, 10 Years 1,108
Buffalo Growth Fund | Buffalo Growth Fund Institutional Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 79
Expense Example, with Redemption, 3 Years 246
Expense Example, with Redemption, 5 Years 428
Expense Example, with Redemption, 10 Years 954
Buffalo Growth & Income Fund | Buffalo Growth & Income Fund Investor Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 94
Expense Example, with Redemption, 3 Years 293
Expense Example, with Redemption, 5 Years 509
Expense Example, with Redemption, 10 Years 1,131
Buffalo Growth & Income Fund | Buffalo Growth & Income Fund Institutional Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 80
Expense Example, with Redemption, 3 Years 249
Expense Example, with Redemption, 5 Years 433
Expense Example, with Redemption, 10 Years 966
Buffalo High Yield Fund | Buffalo High Yield Fund Investor Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 104
Expense Example, with Redemption, 3 Years 325
Expense Example, with Redemption, 5 Years 563
Expense Example, with Redemption, 10 Years 1,248
Buffalo High Yield Fund | Buffalo High Yield Fund Institutional Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 89
Expense Example, with Redemption, 3 Years 278
Expense Example, with Redemption, 5 Years 482
Expense Example, with Redemption, 10 Years 1,073
Buffalo International Fund | Buffalo International Fund Investor Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 106
Expense Example, with Redemption, 3 Years 331
Expense Example, with Redemption, 5 Years 574
Expense Example, with Redemption, 10 Years 1,271
Buffalo International Fund | Buffalo International Fund Institutional Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 91
Expense Example, with Redemption, 3 Years 284
Expense Example, with Redemption, 5 Years 493
Expense Example, with Redemption, 10 Years 1,096
Buffalo Mid Cap Discovery Fund | Buffalo Mid Cap Discovery Fund Investor Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 104
Expense Example, with Redemption, 3 Years 325
Expense Example, with Redemption, 5 Years 563
Expense Example, with Redemption, 10 Years 1,248
Buffalo Mid Cap Discovery Fund | Buffalo Mid Cap Discovery Fund Institutional Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 89
Expense Example, with Redemption, 3 Years 278
Expense Example, with Redemption, 5 Years 482
Expense Example, with Redemption, 10 Years 1,073
Buffalo Mid Cap Growth Fund | Buffalo Mid Cap Growth Fund Investor Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 105
Expense Example, with Redemption, 3 Years 328
Expense Example, with Redemption, 5 Years 569
Expense Example, with Redemption, 10 Years 1,259
Buffalo Mid Cap Growth Fund | Buffalo Mid Cap Growth Fund Institutional Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 91
Expense Example, with Redemption, 3 Years 284
Expense Example, with Redemption, 5 Years 493
Expense Example, with Redemption, 10 Years 1,096
Buffalo Small Cap Growth Fund | Buffalo Small Cap Growth Fund Investor Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 101
Expense Example, with Redemption, 3 Years 315
Expense Example, with Redemption, 5 Years 547
Expense Example, with Redemption, 10 Years 1,213
Buffalo Small Cap Growth Fund | Buffalo Small Cap Growth Fund Institutional Class  
Prospectus [Line Items]  
Expense Example, with Redemption, 1 Year 89
Expense Example, with Redemption, 3 Years 278
Expense Example, with Redemption, 5 Years 482
Expense Example, with Redemption, 10 Years $ 1,073