Objective, Primary [Text Block]

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Risk/Return [Heading]

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AlphaSimplex Global Alternatives Fund

Objective [Heading]

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Investment Goal

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The Fund pursues an absolute return strategy that seeks to provide capital appreciation consistent with the risk-return characteristics of a diversified portfolio of hedge funds.

Objective, Secondary [Text Block]

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The secondary goal of the Fund is to achieve these returns with less volatility than major equity indices.

Expense [Heading]

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Fund Fees & Expenses

Expense Narrative [Text Block]

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The following 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 this table. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the Natixis Funds Complex. More information about these and other discounts is available from your financial professional and in the section “How Sales Charges Are Calculated” on page 85 of the Prospectus, in Appendix A to the Prospectus and on page 130 in the section “Reduced Sales Charges” of the Statement of Additional Information (“SAI”).

Shareholder Fees Caption [Text]

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Shareholder Fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

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Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Fee Waiver or Reimbursement over Assets, Date of Termination

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April 30, 2024

Portfolio Turnover [Heading]

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Portfolio Turnover

Portfolio Turnover [Text Block]

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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 for you if your 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 its most recently ended fiscal year, the Fund’s portfolio turnover rate was 124% of the average value of its portfolio.

Portfolio Turnover, Rate

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124.00%

Expenses Deferred Charges [Text Block]

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A 1.00% contingent deferred sales charge (“CDSC”) may apply to certain purchases of Class A shares of $1,000,000 or more that are redeemed within eighteen months of the date of purchase.

Expense Breakpoint Discounts [Text]

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You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the Natixis Funds Complex.

Expense Breakpoint, Minimum Investment Required [Amount]

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$ 50,000

Other Expenses, New Fund, Based on Estimates [Text]

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Other expenses for Class T shares are estimated for the current fiscal year.

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

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The expense information shown in the table above includes acquired fund fees and expenses of less than 0.01%; the ratios differ from the expense information disclosed in the Fund’s financial highlights table because the financial highlights table reflects the operating expenses of the Fund and does not include acquired fund fees and expenses.

Expense Example [Heading]

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Example

Expense Example Narrative [Text Block]

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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 (except where indicated). The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same, except that the example is based on the Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement assuming that such waiver and/or reimbursement will only be in place through the date noted above and on the Total Annual Fund Operating Expenses for the remaining periods. The example for Class C shares for the ten-year period reflects the conversion to Class A shares after eight years. The example does not take into account brokerage commissions and other fees to financial intermediaries that you may pay on your purchases and sales of shares of the Fund. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Expense Example by, Year, Caption [Text]

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If shares are redeemed:

Expense Example, No Redemption, By Year, Caption [Text]

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If shares are not redeemed:

Strategy [Heading]

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Investments, Risks and Performance Principal Investment Strategies

Strategy Narrative [Text Block]

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The Fund seeks to achieve long and short exposure to global equity, bond, currency and commodity markets through a wide range of derivative instruments and direct investments. Under normal market conditions, the Adviser typically will make extensive use of derivative instruments, in particular futures, forward contracts and swaps on global equity and fixed-income securities, securities indices (including both broad- and narrow-based securities indices), currencies, commodities and other instruments. These investments are intended to provide the Fund with risk and return characteristics similar to those of a diversified portfolio of hedge funds. The Fund may also make direct long and short investments in equity and fixed-income securities.

The Fund seeks to generate absolute returns over time rather than track the performance of any particular index of hedge fund returns. In selecting investments for the Fund, the Adviser uses quantitative models to estimate the market exposures that drive the aggregate returns of a diverse set of hedge funds. The Adviser seeks to capture these market exposures in the aggregate while adding value through dynamic allocation among market exposures and volatility management. These market exposures may include, for example, exposures to the returns of stocks, fixed-income securities (including U.S. and non-U.S. government securities, as well as corporate debt securities), currencies and commodities. In estimating these market exposures, the Adviser may use various approaches, including analyses of the returns of hedge funds included in one or more commercially available databases selected by the Adviser (for example, the Lipper TASS hedge fund database) and regulatory filings. The Fund may also directly employ various strategies commonly used by hedge funds that seek to profit from underlying risk factors, such as merger arbitrage and trend-following strategies. In a merger arbitrage strategy, the Adviser buys shares of target companies in corporate reorganizations and establishes short positions in shares of the acquiring companies. Trend-following strategies analyze markets over various time horizons to invest either long or short in assets whose values are rising or falling, respectively.

The Adviser will have great flexibility to allocate the Fund’s exposure among various securities, indices, currencies, commodities and other instruments; the amount of the Fund’s assets that may be allocated to various strategies and among investments is expected to vary over time. When buying and selling securities and other instruments for the Fund, the Adviser also may consider other factors, such as: (i) the Fund’s obligations under its various derivative positions; (ii) portfolio rebalancing; (iii) redemption requests; (iv) yield management; (v) credit management; and (vi) volatility management. The Fund will not invest directly in hedge funds. The Fund may invest in non-U.S. securities and instruments and securities and instruments traded outside the United States, and expects to engage in non-U.S. currency transactions.

The Adviser currently targets an annualized volatility level of 9% or less (as measured by the standard deviation of the Fund’s returns). The Fund’s actual or realized volatility during certain periods or over time may materially exceed its target volatility for various reasons, including changes in market levels of volatility and because the Fund’s portfolio may include instruments that are inherently volatile. This would increase the risk of investing in the Fund.

Under normal market conditions, it is expected that no more than 25% of the Fund’s total assets will be dedicated to initial and variation margin payments relating to the Fund’s derivative transactions. The gross notional value of the Fund’s derivative investments, however, will generally exceed 25% of the Fund’s assets, and may significantly exceed the total value of the Fund’s assets. The Adviser will invest a portion of the Fund’s assets, which may vary over time, in short-term, high-quality securities. Such investments will be used primarily to finance the Fund’s investments in derivatives and, secondarily, to provide the Fund with incremental income and liquidity, and may include: (i) short-term obligations issued or guaranteed by the United States government, its agencies or instrumentalities; (ii) securities issued by foreign governments, their political subdivisions or agencies or instrumentalities; (iii) certificates of deposit, time deposits and bankers’ acceptances issued by domestic banks, foreign branches of domestic banks, foreign subsidiaries of domestic banks, and domestic and foreign branches of foreign banks; (iv) variable amount master demand notes; (v) participation interests in loans extended by banks to companies; (vi) commercial paper or similar debt obligations; and (vii) repurchase agreements. The Adviser will select such investments based on various factors, including the security’s maturity and credit rating.

Although the Fund does not intend to invest in physical commodities directly, the Fund expects to obtain investment exposure to commodities and commodity-related derivatives through a wholly-owned subsidiary organized under the laws of the Cayman Islands that will make commodity-related investments (the “Commodity Subsidiary”). The Fund may invest up to 25% of its total assets in the Commodity Subsidiary. Under normal market conditions, no more than 10% of the Fund’s total assets will be dedicated to initial and variation margin payments relating to these transactions.

The Fund will concentrate its investments in the financial services industry, which means it will normally invest at least 25% of its total assets in securities and other obligations (for example, bank certificates of deposit) of issuers in such industry. The Fund may engage in active and frequent trading of securities and other instruments. Effects of frequent trading may include high transaction costs, which may lower the Fund’s return, and realization of greater short-term capital gains, distributions of which are taxable as ordinary income to taxable shareholders. Trading costs and tax effects associated with frequent trading may adversely affect the Fund’s performance. The Fund’s trading in derivatives is active and frequent. Active and frequent trading of derivatives, like active and frequent trading of securities, will result in transaction costs which reduce fund returns.

The percentage limitations set forth herein are not investment restrictions and the Fund may exceed these limits from time to time.

The Fund's shareholders approved an Agreement and Plan of Reorganization (the "Agreement") which provides for the reorganization of the Fund with and into the Virtus AlphaSimplex Global Alternatives Fund. It is expected that on or about May 20, 2023 (the "Closing Date"), the Fund will transfer its assets and liabilities to the Virtus AlphaSimplex Global Alternatives Fund, and the Fund will subsequently liquidate. In connection with the reorganization, shareholders of the Fund will receive shares of the Virtus AlphaSimplex Global Alternatives Fund that are equal in aggregate net asset value to the shares of the Fund held on the Closing Date. Additional information on the arrangements will be provided in supplements or other documents provided to the shareholders if these events do not occur substantially in accordance with the schedule outlined above.

Risk [Heading]

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Principal Investment Risks

Risk Narrative [Text Block]

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The principal risks of investing in the Fund are summarized below. The Fund does not represent a complete investment program. You may lose money by investing in the Fund.

Fund shares are not bank deposits and are not guaranteed, endorsed or insured by the Federal Deposit Insurance Corporation or any other government agency, and are subject to investment risks, including possible loss of the principal invested.

The significance of any specific risk to an investment in the Fund will vary over time, depending on the composition of the Fund’s portfolio, market conditions, and other factors. You should read all of the risk information presented below carefully, because any one or more of these risks may result in losses to the Fund.

Leverage Risk: Taking short positions in securities results in a form of leverage. Leverage is the risk associated with securities or investment practices (e.g., borrowing and the use of certain derivatives) that multiply small index, market or asset-price movements into larger changes in value. The use of leverage increases the impact of gains and losses on the Fund’s returns, and may lead to significant losses if investments are not successful.

Derivatives Risk: Derivative instruments (such as those in which the Fund may invest, including futures, swaps, forward contracts, and other foreign currency transactions and commodity-linked derivatives) are subject to changes in the value of the underlying assets or indices on which such instruments are based. There is no guarantee that the use of derivatives will be effective or that suitable transactions will be available. Even a small investment in derivatives may give rise to leverage risk and can have a significant impact on the Fund’s exposure to commodities markets, securities market values, interest rates or currency exchange rates. It is possible that the Fund’s liquid assets may be insufficient to support its obligations under its derivatives positions. The use of derivatives for other than hedging purposes may be considered a speculative activity, and involves greater risks than are involved in hedging. The use of derivatives may cause the Fund to incur losses greater than those that would have occurred had derivatives not been used. The Fund’s use of derivatives involves other risks, such as credit/counterparty risk relating to the other party to a derivative contract (which is greater for forward currency contracts, uncleared swaps and other over-the-counter (“OTC”) derivatives), the risk of difficulties in pricing and valuation, the risk that changes in the value of a derivative may not correlate as expected with changes in the value of relevant assets, rates or indices, liquidity risk, allocation risk and the risk of losing more than the initial margin (if any) required to initiate derivatives positions. There is also the risk that the Fund may be unable to terminate or sell a derivative position at an advantageous time or price. The Fund’s derivative counterparties may experience financial difficulties or otherwise be unwilling or unable to honor their obligations, possibly resulting in losses to the Fund. There is a risk that the Adviser’s use of derivatives, such as futures and forward contracts, to manage the Fund’s volatility may be ineffective or may exacerbate losses, for example, if the derivative or the underlying assets decrease in value over time.

Equity Securities Risk: The value of the Fund’s investments in equity securities could be subject to unpredictable declines in the value of individual securities and periods of below-average performance in individual securities or in the equity market as a whole. In the event an issuer is liquidated or declares bankruptcy, the claims of owners of the issuer’s bonds generally take precedence over the claims of those who own preferred stock or common stock.

Short Exposure Risk: A short exposure through a derivative or short sale may present various risks, including credit/counterparty risk and leverage risk. If the value of the asset, asset class or index on which the Fund has obtained a short investment exposure increases, the Fund will incur a loss. Unlike a direct cash investment such as a stock, bond or exchange-traded fund (“ETF”), where the potential loss is limited to the purchase price, the potential risk of loss from a short exposure is theoretically unlimited. Moreover, there can be no assurance that securities necessary to cover (repurchase in order to close) a short position will be available for purchase. The Fund may be unable to borrow securities in connection with a short sale or to enter into a short position at an advantageous time or price, which could limit its ability to obtain the desired short exposure.

Models and Data Risk: The Adviser utilizes various proprietary quantitative models to identify investment opportunities. There is a possibility that one or all of the quantitative models may fail to identify profitable opportunities at any time. Furthermore, the models may incorrectly identify opportunities and these misidentified opportunities may lead to substantial losses for the Fund. Models may be predictive in nature and such models may result in an incorrect assessment of future events. Data used in the construction of models may prove to be inaccurate or stale, which may result in losses for the Fund.

Allocation Risk: This is the risk that the Adviser’s judgments about, and allocations between, asset classes and market exposures may adversely affect the Fund’s performance. The allocation, as set forth above, may not be optimal in every market condition. You could lose money on your investment in the Fund as

a result of this allocation. This risk can be increased by the use of derivatives to increase allocations to various market exposures. This is because derivatives can create investment leverage, which will magnify the impact to the Fund of its investment in any underperforming market exposure.

Commodity Risk: This is the risk that exposure to the commodities markets may subject the Fund to greater volatility than investments in traditional securities. The value of physical commodities or commodity-linked derivative instruments may be affected by changes in overall market movements, commodity price volatility, changes in interest rates, currency fluctuations, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, embargoes, tariffs and international economic, political and regulatory developments.

Commodity Subsidiary Risk: Investing in the Commodity Subsidiary will indirectly expose the Fund to the risks associated with the Commodity Subsidiary’s investments, such as commodity risk. The Commodity Subsidiary is not registered under the Investment Company Act of 1940 (the “1940 Act”) and is not subject to all of the investor protections of the 1940 Act. Changes in the laws of the United States and/or the Cayman Islands, under which the Fund and the Commodity Subsidiary, respectively, are organized, could negatively affect the Fund and its shareholders.

Concentrated Investment Risk: The Fund is particularly vulnerable to events affecting companies in the financial services industry because the Fund concentrates its investments in securities and other obligations of issuers in such industry. Examples of risks affecting the financial services industry include changes in governmental regulation, issues relating to the availability and cost of capital, changes in interest rates and/or monetary policy and price competition. In addition, financial services companies are often more highly leveraged than other companies, making them inherently riskier. As a result, the Fund’s shares may rise and fall in value more rapidly and to a greater extent than shares of a fund that does not concentrate or focus in a particular industry or economic sector.

Credit/Counterparty Risk: Credit/counterparty risk is the risk that the issuer or guarantor of a fixed-income security, or the counterparty to a derivative or other transaction, will be unable or unwilling to make timely payments of interest or principal or to otherwise honor its obligations. As a result, the Fund may sustain losses or be unable or delayed in its ability to realize gains. The Fund will be subject to credit/counterparty risk with respect to the counterparties to its derivatives transactions. This risk will be heightened to the extent the Fund enters into derivative transactions with a single counterparty (or affiliated counterparties that are part of the same organization), causing the Fund to have significant exposure to such counterparty. Many of the protections afforded to participants on organized exchanges and clearinghouses, such as the performance guarantee given by a central clearinghouse, are not available in connection with OTC derivatives transactions, such as foreign currency transactions. For centrally cleared derivatives, such as cleared swaps, futures and many options, the primary credit/counterparty risk is the creditworthiness of the Fund’s clearing broker and the central clearinghouse itself.

Currency Risk: Fluctuations in the exchange rates between different currencies may negatively affect an investment. The Fund may be subject to currency risk because it may invest a significant portion of its assets in currency-related instruments and may invest in securities or other instruments denominated in, or that generate income denominated in, foreign currencies. The Fund may elect not to hedge currency risk, or may hedge such risk imperfectly, which may cause the Fund to incur losses that would not have been incurred had the risk been hedged.

Cybersecurity and Technology Risk: The Fund, its service providers, and other market participants increasingly depend on complex information technology and communications systems, which are subject to a number of different threats and risks that could adversely affect the Fund and its shareholders. Cybersecurity and other operational and technology issues may result in financial losses to the Fund and its shareholders.

Foreign Securities Risk: Investments in foreign securities may be subject to greater political, economic, environmental, credit/counterparty and information risks. The Fund’s investments in foreign securities also are subject to foreign currency fluctuations and other foreign currency-related risks. Foreign securities may be subject to higher volatility than U.S. securities, varying degrees of regulation and limited liquidity.

Hedge Fund Risk: Hedge funds are typically unregulated private investment pools available only to sophisticated investors. They are often illiquid and highly leveraged. Although the Fund will not invest directly in hedge funds, because the Fund’s investments are intended to provide exposure to the factors that drive hedge fund returns, an investment in the Fund will be subject to many of the same risks associated with an investment in a diversified portfolio of hedge funds. Therefore, the Fund’s performance may be lower than the returns of the broader stock market and the Fund’s net asset value may fluctuate substantially over time.

Index/Tracking Error Risk: Although the Fund does not seek to track any particular index, the Fund seeks to analyze the factors that drive hedge fund returns, as determined by reference to one or more indices. These indices may not provide an accurate representation of hedge fund returns generally, and the Adviser’s strategy may not successfully identify or be able to replicate factors that drive returns. There is a risk that hedge fund return data provided by third party hedge fund index providers may be inaccurate or may not accurately reflect hedge fund returns due to survivorship bias, self-reporting bias or other biases.

Interest Rate Risk: Interest rate risk is the risk that the value of the Fund’s investments will fall if interest rates rise. Generally, the value of fixed-income securities rises when prevailing interest rates fall and falls when interest rates rise. Interest rate risk generally is greater for funds that invest in fixed-income securities with relatively longer durations than for funds that invest in fixed-income securities with shorter durations. In addition, an economic downturn or period of rising interest rates could adversely affect the market for these securities and reduce the Fund’s ability to sell them, negatively impacting the performance of the Fund. Potential future changes in government and/or central bank monetary policy and action may also affect the level of interest rates. Recently, there have been inflationary price movements, which have caused the fixed income securities markets to experience heightened levels of interest volatility and liquidity risk. The risks associated with rising interest rates may be particularly acute because of recent monetary policy measures.

Investments in Other Investment Companies Risk: The Fund will indirectly bear the management, service and other fees of any other investment companies, including ETFs, in which it invests in addition to its own expenses.

Large Investor Risk: Ownership of shares of the Fund may be concentrated in one or a few large investors. Such investors may redeem shares in large quantities or on a frequent basis. Redemptions by a large investor can affect the performance of the Fund, may increase realized capital gains, including short-term capital gains taxable as ordinary income, may accelerate the realization of taxable income to shareholders and may increase transaction costs. These transactions potentially limit the use of any capital loss carryforwards and certain other losses to offset future realized capital gains (if any). Such transactions may also increase the Fund’s expenses.

Liquidity Risk: Liquidity risk is the risk that the Fund may be unable to find a buyer for its investments when it seeks to sell them or to receive the price it expects. Decreases in the number of financial institutions willing to make markets in the Fund’s investments or in their capacity or willingness to transact may increase the Fund’s exposure to this risk. Events that may lead to increased redemptions, such as market disruptions or increases in interest rates, may also negatively impact the liquidity of the Fund’s investments when it needs to dispose of them. If the Fund is forced to sell its investments at an unfavorable time and/or under adverse conditions in order to meet redemption requests, such sales could negatively affect the Fund. During times of market turmoil, there may be no buyers or sellers for securities in certain asset classes. In other circumstances, liquid investments may become illiquid. Derivatives, and particularly OTC derivatives, are generally subject to liquidity risk as well. Liquidity issues may also make it difficult to value the Fund’s investments. The Fund may invest in liquid investments that become illiquid due to financial distress, or geopolitical events such as sanctions, trading halts or wars.

Management Risk: A strategy used by the Fund’s portfolio managers may fail to produce the intended result.

Market/Issuer Risk: The market value of the Fund’s investments will move up and down, sometimes rapidly and unpredictably, based upon overall market and economic conditions, as well as a number of reasons that directly relate to the issuers of the Fund’s investments, such as management performance, financial condition and demand for the issuers’ goods and services. The Adviser will attempt to reduce this risk by implementing various volatility management strategies and techniques. However, there is no guarantee that such strategies and techniques will produce the intended result.

Portfolio Turnover Rate Risk: The Fund may engage in active and frequent trading of portfolio securities to pursue its principal investment strategy. A high rate of portfolio turnover may involve correspondingly greater expenses, which must be borne by the Fund and its shareholders, and also may result in short-term capital gains or losses to shareholders.

U.S. Government Securities Risk: Investments in certain U.S. government securities may not be supported by the full faith and credit of the U.S. government. Accordingly, no assurance can be given that the U.S. government will provide financial support to U.S. government agencies, instrumentalities or sponsored enterprises if it is not obligated to do so by law. The maximum potential liability of the issuers of some U.S. government securities held by the Fund may greatly exceed their current resources, and it is possible that these issuers will not have the funds to meet their payment obligations in the future. In such a case, the Fund would have to look principally to the agency, instrumentality or sponsored enterprise issuing or guaranteeing the security for ultimate repayment, and the Fund may not be able to assert a claim against the U.S. government itself in the event the agency, instrumentality or sponsored enterprise does not meet its commitment. Concerns about the capacity or willingness of the U.S. government to meet its obligations may raise the interest rates payable on its securities, negatively impacting the price of such securities already held by the Fund.

Valuation Risk: This is the risk that the Fund has valued certain securities or positions at a higher price than the price at which they can be sold. This risk may be especially pronounced for investments, such as derivatives, that may be illiquid or may become illiquid.

Risk Lose Money [Text]

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You may lose money by investing in the Fund.

RIsk Not Insured [Text]

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Bar Chart and Performance Table [Heading]

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Risk/Return Bar Chart and Table

Performance Narrative [Text Block]

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The bar chart and table shown below provide some indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year-to-year and by showing how the Fund’s average annual returns for the one-year, five-year, ten-year and life-of-class periods (as applicable) compare to those of a broad measure of market performance. The Barclay Fund of Funds Index is a measure of the average return of all funds of funds in the Barclay database. Performance for Class C shares includes the automatic conversion to Class A shares after eight years. The Fund’s past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated performance information is available online at im.natixis.com and/or by calling the Fund toll-free at 800-225-5478.

The chart does not reflect any sales charge that you may be required to pay when you buy or redeem the Fund’s shares. A sales charge will reduce your return.

Performance Information Illustrates Variability of Returns [Text]

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Performance Availability Phone [Text]

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800-225-5478

Performance Availability Website Address [Text]

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im.natixis.com

Performance Past Does Not Indicate Future [Text]

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The Fund’s past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future.

Bar Chart [Heading]

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Total Returns for Class Y Shares

Bar Chart Does Not Reflect Sales Loads [Text]

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The chart does not reflect any sales charge that you may be required to pay when you buy or redeem the Fund’s shares. A sales charge will reduce your return.

Bar Chart Closing [Text Block]

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Highest Quarterly Return:First Quarter 2015, 5.96%Lowest Quarterly Return:First Quarter 2020, -9.51%

Performance Table Heading

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Average Annual Total Returns (for the periods ended December 31, 2022)

Index No Deduction for Fees, Expenses, Taxes [Text]

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Index performance reflects no deduction for fees, expenses or taxes, but does reflect the management fees and other expenses of both the funds of funds in the index and the hedge funds in which those funds of funds invest.

Performance Table Uses Highest Federal Rate

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After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

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Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their shares through tax-advantaged arrangements, such as 401(k) plans, qualified plans, education savings accounts, such as 529 plans, or individual retirement accounts.

Performance Table One Class of after Tax Shown [Text]

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The after-tax returns are shown for only one class of the Fund.After-tax returns for the other classes of the Fund will vary.

Performance Table Explanation after Tax Higher

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The Return After Taxes on Distributions and Sale of Fund Shares for the 1-year period exceeds the Return Before Taxes due to an assumed tax benefit from losses on a sale of Fund shares at the end of the measurement period.

Performance Table Closing [Text Block]

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The Fund did not have Class T shares outstanding during the periods shown above. The returns of Class T shares would have been substantially similar to the returns of the Fund’s other share classes because they would have been invested in the same portfolio of securities and would only differ to the extent the other share classes did not have the same expenses. Performance of Class T shares shown above is that of Class A shares, which have the same expenses as Class T shares, restated to reflect the different sales load applicable to Class T shares.

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their shares through tax-advantaged arrangements, such as 401(k) plans, qualified plans, education savings accounts, such as 529 plans, or individual retirement accounts. The after-tax returns are shown for only one class of the Fund. After-tax returns for the other classes of the Fund will vary. Index performance reflects no deduction for fees, expenses or taxes, but does reflect the management fees and other expenses of both the funds of funds in the index and the hedge funds in which those funds of funds invest. The Return After Taxes on Distributions and Sale of Fund Shares for the 1-year period exceeds the Return Before Taxes due to an assumed tax benefit from losses on a sale of Fund shares at the end of the measurement period.

AlphaSimplex Global Alternatives Fund | Class A

Maximum sales charge (load) imposed on purchases (as a percentage of offering price)

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rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

5.75%

Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, as applicable)

rr_MaximumDeferredSalesChargeOverOther

none

^[1]

rr_RedemptionFee

none

rr_ManagementFeesOverAssets

1.10%

rr_DistributionAndService12b1FeesOverAssets

0.25%

rr_OtherExpensesOverAssets

0.29%

rr_ExpensesOverAssets

1.64%

^[2]

Total annual fund operating expenses after fee waiver and/or expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.14%

rr_NetExpensesOverAssets

1.50%

^[3],[4]

rr_ExpenseExampleYear01

$ 719

rr_ExpenseExampleYear03

1,050

rr_ExpenseExampleYear05

1,403

rr_ExpenseExampleYear10

$ 2,396

rr_AverageAnnualReturnYear01

(6.52%)

rr_AverageAnnualReturnYear05

(0.97%)

rr_AverageAnnualReturnYear10

1.62%

AlphaSimplex Global Alternatives Fund | Class C

rr_AverageAnnualReturnSinceInception

Maximum sales charge (load) imposed on purchases (as a percentage of offering price)

rr_RiskReturnAbstract

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, as applicable)

rr_MaximumDeferredSalesChargeOverOther

1.00%

rr_RedemptionFee

none

rr_ManagementFeesOverAssets

1.10%

rr_DistributionAndService12b1FeesOverAssets

1.00%

rr_OtherExpensesOverAssets

0.29%

rr_ExpensesOverAssets

2.39%

^[2]

Total annual fund operating expenses after fee waiver and/or expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.14%

rr_NetExpensesOverAssets

2.25%

^[3],[4]

rr_ExpenseExampleYear01

$ 328

rr_ExpenseExampleYear03

732

rr_ExpenseExampleYear05

1,263

rr_ExpenseExampleYear10

2,529

rr_ExpenseExampleNoRedemptionYear01

228

rr_ExpenseExampleNoRedemptionYear03

732

rr_ExpenseExampleNoRedemptionYear05

1,263

rr_ExpenseExampleNoRedemptionYear10

$ 2,529

rr_AverageAnnualReturnYear01

(2.41%)

rr_AverageAnnualReturnYear05

(0.55%)

rr_AverageAnnualReturnYear10

1.61%

AlphaSimplex Global Alternatives Fund | Class N

rr_AverageAnnualReturnSinceInception

Maximum sales charge (load) imposed on purchases (as a percentage of offering price)

rr_RiskReturnAbstract

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, as applicable)

rr_MaximumDeferredSalesChargeOverOther

none

rr_RedemptionFee

none

rr_ManagementFeesOverAssets

1.10%

rr_DistributionAndService12b1FeesOverAssets

none

rr_OtherExpensesOverAssets

0.22%

rr_ExpensesOverAssets

1.32%

^[2]

Total annual fund operating expenses after fee waiver and/or expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.12%

rr_NetExpensesOverAssets

1.20%

^[3],[4]

rr_ExpenseExampleYear01

$ 122

rr_ExpenseExampleYear03

406

rr_ExpenseExampleYear05

712

rr_ExpenseExampleYear10

$ 1,580

rr_AverageAnnualReturnYear01

(0.56%)

rr_AverageAnnualReturnYear05

0.49%

rr_AverageAnnualReturnYear10

AlphaSimplex Global Alternatives Fund | Class T

rr_AverageAnnualReturnSinceInception

1.84%

Inception Date

rr_AverageAnnualReturnInceptionDate

May 01, 2013

Maximum sales charge (load) imposed on purchases (as a percentage of offering price)

rr_RiskReturnAbstract

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

2.50%

Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, as applicable)

rr_MaximumDeferredSalesChargeOverOther

none

rr_RedemptionFee

none

rr_ManagementFeesOverAssets

1.10%

rr_DistributionAndService12b1FeesOverAssets

0.25%

rr_OtherExpensesOverAssets

0.29%

^[5]

rr_ExpensesOverAssets

1.64%

^[2]

Total annual fund operating expenses after fee waiver and/or expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.14%

rr_NetExpensesOverAssets

1.50%

^[3],[4]

rr_ExpenseExampleYear01

$ 399

rr_ExpenseExampleYear03

741

rr_ExpenseExampleYear05

1,107

rr_ExpenseExampleYear10

$ 2,134

rr_AverageAnnualReturnYear01

(3.31%)

rr_AverageAnnualReturnYear05

(0.30%)

rr_AverageAnnualReturnYear10

1.97%

AlphaSimplex Global Alternatives Fund | Class Y

rr_AverageAnnualReturnSinceInception

Maximum sales charge (load) imposed on purchases (as a percentage of offering price)

rr_RiskReturnAbstract

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum deferred sales charge (load) (as a percentage of original purchase price or redemption proceeds, as applicable)

rr_MaximumDeferredSalesChargeOverOther

none

rr_RedemptionFee

none

rr_ManagementFeesOverAssets

1.10%

rr_DistributionAndService12b1FeesOverAssets

none

rr_OtherExpensesOverAssets

0.29%

rr_ExpensesOverAssets

1.39%

^[2]

Total annual fund operating expenses after fee waiver and/or expense reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.14%

rr_NetExpensesOverAssets

1.25%

^[3],[4]

rr_ExpenseExampleYear01

$ 127

rr_ExpenseExampleYear03

426

rr_ExpenseExampleYear05

747

Highest Quarterly Return, Label

rr_ExpenseExampleYear10

$ 1,656

2013

rr_AnnualReturn2013

16.05%

2014

rr_AnnualReturn2014

3.77%

2015

rr_AnnualReturn2015

(2.38%)

2016

rr_AnnualReturn2016

(4.23%)

2017

rr_AnnualReturn2017

10.93%

2018

rr_AnnualReturn2018

(6.04%)

2019

rr_AnnualReturn2019

10.49%

2020

rr_AnnualReturn2020

(2.12%)

2021

rr_AnnualReturn2021

1.29%

2022

rr_AnnualReturn2022

(0.53%)

rr_HighestQuarterlyReturnLabel

Highest Quarterly Return:

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2015

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

5.96%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Quarterly Return:

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Mar. 31, 2020

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(9.51%)

rr_AverageAnnualReturnYear01

(0.53%)

rr_AverageAnnualReturnYear05

0.47%

rr_AverageAnnualReturnYear10

2.49%

AlphaSimplex Global Alternatives Fund | Return After Taxes on Distributions | Class Y

rr_AverageAnnualReturnSinceInception

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

(4.01%)

rr_AverageAnnualReturnYear05

(0.62%)

rr_AverageAnnualReturnYear10

1.33%

AlphaSimplex Global Alternatives Fund | Return After Taxes on Distributions and Sale of Fund Shares | Class Y

rr_AverageAnnualReturnSinceInception

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

(0.25%)

rr_AverageAnnualReturnYear05

(0.07%)

rr_AverageAnnualReturnYear10

1.52%

AlphaSimplex Global Alternatives Fund | Barclay Fund of Funds Index

rr_AverageAnnualReturnSinceInception

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

(9.74%)

rr_AverageAnnualReturnYear05

1.10%

AlphaSimplex Global Alternatives Fund | Barclay Fund of Funds Index | Class N

rr_AverageAnnualReturnYear10

2.21%

rr_RiskReturnAbstract