v3.26.1
Fees and Expenses
Jul. 29, 2026
Buffalo Blue Chip Growth Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.
Acquired Fund Fees and Expenses, Based on Estimates [Text] Acquired Fund Fees and Expenses represent the indirect costs of the Fund’s investments in other investment companies.
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] The Total Annual Fund Operating Expenses for each Class of the Fund do not correlate to the ratio of expenses to average net assets listed in the Fund’s financial highlights, which reflects the operating expenses of each Class of the Fund and does not include the amount of the Fund’s proportionate share of the fees and expenses of other investment companies in which each Class of the Fund invests.
Shareholder Fees Caption [Optional Text] Shareholder Fees(fees paid directly from your investment)
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading] Example
Expense Example Narrative [Text Block] This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same.
Expense Example by, Year, Caption [Text] Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block] The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 52% of the average value of its portfolio.
Portfolio Turnover, Rate 52.00%
Buffalo Early Stage Growth Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.
Shareholder Fees Caption [Optional Text] Shareholder Fees(fees paid directly from your investment)
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses(expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading] Example
Expense Example Narrative [Text Block] This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same.
Expense Example by, Year, Caption [Text] Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block] The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 48% of the average value of its portfolio.
Portfolio Turnover, Rate 48.00%
Buffalo Flexible Allocation Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.
Shareholder Fees Caption [Optional Text] Shareholder Fees(fees paid directly from your investment)
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses(expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading] Example
Expense Example Narrative [Text Block] This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same.
Expense Example by, Year, Caption [Text] Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block] The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 0% of the average value of its portfolio.
Portfolio Turnover, Rate none
Buffalo Growth Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.
Shareholder Fees Caption [Optional Text] Shareholder Fees(fees paid directly from your investment)
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses(expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading] Example
Expense Example Narrative [Text Block] This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same.
Expense Example by, Year, Caption [Text] Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block] The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 10% of the average value of its portfolio.
Portfolio Turnover, Rate 10.00%
Buffalo Growth & Income Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] The Total Annual Fund Operating Expenses for each Class of the Fund do not correlate to the ratio of expenses to average net assets listed in the Fund’s financial highlights, which reflects the operating expenses of each Class of the Fund and does not include the amount of the Fund’s proportionate share of the fees and expenses of other investment companies in which each Class of the Fund invests.
Shareholder Fees Caption [Optional Text] Shareholder Fees(fees paid directly from your investment)
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses(expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading] Example
Expense Example Narrative [Text Block] This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same.
Expense Example by, Year, Caption [Text] Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block] The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 4% of the average value of its portfolio.
Portfolio Turnover, Rate 4.00%
Buffalo High Yield Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] The Total Annual Fund Operating Expenses for each Class of the Fund do not correlate to the ratio of expenses to average net assets listed in the Fund’s financial highlights, which reflects the operating expenses of each Class of the Fund and does not include the amount of the Fund’s proportionate share of the fees and expenses of other investment companies in which each Class of the Fund invests.
Shareholder Fees Caption [Optional Text] Shareholder Fees(fees paid directly from your investment)
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses(expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading] Example
Expense Example Narrative [Text Block] This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same.
Expense Example by, Year, Caption [Text] Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block] The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 39% of the average value of its portfolio.
Portfolio Turnover, Rate 39.00%
Buffalo International Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] The Total Annual Fund Operating Expenses for each Class of the Fund do not correlate to the ratio of expenses to average net assets listed in the Fund’s financial highlights, which reflects the operating expenses of each Class of the Fund and does not include the amount of the Fund’s proportionate share of the fees and expenses of other investment companies in which each Class of the Fund invests.
Shareholder Fees Caption [Optional Text] Shareholder Fees(fees paid directly from your investment)
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses(expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading] Example
Expense Example Narrative [Text Block] This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same.
Expense Example by, Year, Caption [Text] Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block] The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 16% of the average value of its portfolio.
Portfolio Turnover, Rate 16.00%
Buffalo Mid Cap Discovery Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] The Total Annual Fund Operating Expenses for each Class of the Fund do not correlate to the ratio of expenses to average net assets listed in the Fund’s financial highlights, which reflects the operating expenses of each Class of the Fund and does not include the amount of the Fund’s proportionate share of the fees and expenses of other investment companies in which each Class of the Fund invests.
Shareholder Fees Caption [Optional Text] Shareholder Fees(fees paid directly from your investment)
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses(expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading] Example
Expense Example Narrative [Text Block] This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year, and that the Fund’s operating expenses remain the same.
Expense Example by, Year, Caption [Text] Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block] The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 74% of the average value of its portfolio.
Portfolio Turnover, Rate 74.00%
Buffalo Mid Cap Growth Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] The Total Annual Fund Operating Expenses for each Class of the Fund do not correlate to the ratio of expenses to average net assets listed in the Fund’s financial highlights, which reflects the operating expenses of each Class of the Fund and does not include the amount of the Fund’s proportionate share of the fees and expenses of other investment companies in which each Class of the Fund invests.
Shareholder Fees Caption [Optional Text] Shareholder Fees(fees paid directly from your investment)
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses(expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading] Example
Expense Example Narrative [Text Block] This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same.
Expense Example by, Year, Caption [Text] Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block] The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 39% of the average value of its portfolio.
Portfolio Turnover, Rate 39.00%
Buffalo Small Cap Growth Fund  
Prospectus [Line Items]  
Expense Heading [Optional Text] FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block]
This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and example below.
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text] The Total Annual Fund Operating Expenses for each Class of the Fund do not correlate to the ratio of expenses to average net assets listed in the Fund’s financial highlights, which reflects the operating expenses of each Class of the Fund and does not include the amount of the Fund’s proportionate share of the fees and expenses of other investment companies in which each Class of the Fund invests.
Shareholder Fees Caption [Optional Text] Shareholder Fees(fees paid directly from your investment)
Operating Expenses Caption [Optional Text] Annual Fund Operating Expenses(expenses that you pay each year as a percentage of the value of your investment)
Expense Example [Heading] Example
Expense Example Narrative [Text Block] This example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same.
Expense Example by, Year, Caption [Text] Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Portfolio Turnover [Heading] Portfolio Turnover
Portfolio Turnover [Text Block] The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 37% of the average value of its portfolio.
Portfolio Turnover, Rate 37.00%