S000054634 [Member] Fees and Expenses - NexPoint Merger Arbitrage Fund	Jun. 30, 2026 USD ($)
Prospectus [Line Items]
Expense Heading [Optional Text]	Fees and Expenses of the Fund
Expense Narrative [Text Block]	The following tables describe 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 examples. You may qualify for sales charge discounts on purchases of Class A Shares if you and your family invest, or agree to invest in the future, at least $50,000 in the Fund. More information about these and other discounts is available from your financial professional and in the “Reduced Sales Charges for Class A Shares” section on page 57 of the Fund’s Prospectus and the “Programs for Reducing or Eliminating Sales Charges” section on page 55 of the Fund’s Statement of Additional Information. Investors investing in the Fund through an intermediary should consult the Appendix to the Fund’s Prospectus, which includes information regarding financial intermediary-specific sales charges and related discount policies that apply to purchases through certain specified intermediaries.
Expense Breakpoint Discounts [Text]	You may qualify for sales charge discounts on purchases of Class A Shares if you and your family invest, or agree to invest in the future, at least $50,000 in the Fund. More information about these and other discounts is available from your financial professional and in the “Reduced Sales Charges for Class A Shares” section on page 57 of the Fund’s Prospectus and the “Programs for Reducing or Eliminating Sales Charges” section on page 55 of the Fund’s Statement of Additional Information.
Expense Breakpoint, Minimum Investment Required [Amount]	$ 50,000
Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]	Total Annual Fund Operating Expenses differ from the ratios of expenses to average net assets shown in the Financial Highlights, which reflect the operating expenses of the Fund and do not include acquired fund fees and expenses.
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)3
Expenses Deferred Charges [Text Block]	Class A Shares bought without an initial sales charge in accounts aggregating $500,000 or more at the time of purchase are subject to a 1.00% contingent deferred sales charge (“CDSC”) if the shares are sold within 18 months of purchase.Class C Shares are subject to a 1% CDSC for redemptions of shares within one year of purchase. This CDSC does not apply to redemptions under a systematic withdrawal plan.
Expense Example [Heading]	Expense Example
Expense Example Narrative [Text Block]	This Example helps you compare the cost of investing in the Fund to the cost of investing in other mutual funds. The Example assumes that (i) you invest $10,000 in the Fund for the time periods indicated and then sell or redeem all your shares at the end of those periods, (ii) your investment has a 5% return each year, and (iii) operating expenses remain the same. Only the first year of each period in the Example takes into account the expense reimbursement described above. Your actual costs may be higher or lower.
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 Expense Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 377% of the average value of its portfolio.
Portfolio Turnover, Rate	377.00%

S000054634 [Member] Fees and Expenses - NexPoint Merger Arbitrage Fund

Jun. 30, 2026

USD ($)

Fees and Expenses of the Fund

The following tables describe 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 examples.

You may qualify for sales charge discounts on purchases of Class A Shares if you and your family invest, or agree to invest in the future, at least $50,000 in the Fund. More information about these and other discounts is available from your financial professional and in the “Reduced Sales Charges for Class A Shares” section on page 57 of the Fund’s Prospectus and the “Programs for Reducing or Eliminating Sales Charges” section on page 55 of the Fund’s Statement of Additional Information. Investors investing in the Fund through an intermediary should consult the Appendix to the Fund’s Prospectus, which includes information regarding financial intermediary-specific sales charges and related discount policies that apply to purchases through certain specified intermediaries.

Expense Breakpoint Discounts [Text]

Expense Breakpoint, Minimum Investment Required [Amount]

$ 50,000

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

Total Annual Fund Operating Expenses differ from the ratios of expenses to average net assets shown in the Financial Highlights, which reflect the operating expenses of the Fund and do not include acquired fund fees and expenses.

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)3

Expenses Deferred Charges [Text Block]

Class A Shares bought without an initial sales charge in accounts aggregating $500,000 or more at the time of purchase are subject to a 1.00% contingent deferred sales charge (“CDSC”) if the shares are sold within 18 months of purchase.Class C Shares are subject to a 1% CDSC for redemptions of shares within one year of purchase. This CDSC does not apply to redemptions under a systematic withdrawal plan.

Expense Example [Heading]

Expense Example

Expense Example Narrative [Text Block]

This Example helps you compare the cost of investing in the Fund to the cost of investing in other mutual funds. The Example assumes that (i) you invest $10,000 in the Fund for the time periods indicated and then sell or redeem all your shares at the end of those periods, (ii) your investment has a 5% return each year, and (iii) operating expenses remain the same. Only the first year of each period in the Example takes into account the expense reimbursement described above. Your actual costs may be higher or lower.

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 Expense Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 377% of the average value of its portfolio.

Portfolio Turnover, Rate

377.00%