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Label Element Value
Prospectus [Line Items] rr_ProspectusLineItems  
Document Type dei_DocumentType 497
Document Period End Date dei_DocumentPeriodEndDate Feb. 14, 2025
Entity Registrant Name dei_EntityRegistrantName THE RBB FUND, INC.
Entity Central Index Key dei_EntityCentralIndexKey 0000831114
Entity Inv Company Type dei_EntityInvCompanyType N-1A
Amendment Flag dei_AmendmentFlag false
Document Creation Date dei_DocumentCreationDate Feb. 19, 2025
Document Effective Date dei_DocumentEffectiveDate Feb. 19, 2025
Prospectus Date rr_ProspectusDate Feb. 14, 2025
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk/Return [Heading] rr_RiskReturnHeading SUMMARY SECTION – F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF (RBIL)
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock

The investment objective of the F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF (the “F/m Ultrashort TIPS Fund” or the “Fund”) is to seek investment results that correspond (before fees and expenses) generally to the price and yield performance of the Bloomberg U.S. Ultrashort TIPS 1-13 Months Total Return Unhedged USD Index (I39232US).
Expense [Heading] rr_ExpenseHeading Fees and Expenses
Expense Narrative [Text Block] rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the F/m Ultrashort TIPS Fund (“Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Operating Expenses Caption [Text] rr_OperatingExpensesCaption Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
Portfolio Turnover [Heading] rr_PortfolioTurnoverHeading Portfolio Turnover
Portfolio Turnover [Text Block] rr_PortfolioTurnoverTextBlock

The F/m Ultrashort TIPS 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 the 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. No portfolio turnover rate is provided for the Fund because the Fund did not commence operations prior to the date of this Prospectus.
Expense Example [Heading] rr_ExpenseExampleHeading Example
Expense Example Narrative [Text Block] rr_ExpenseExampleNarrativeTextBlock

This Example is intended to help you compare the cost of investing in the F/m Ultrashort TIPS Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then hold or redeem all of your Shares at the end of those periods. The Example also assumes that: (1) your investment has a 5% return each year, and (2) the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading] rr_StrategyHeading Principal Investment Strategies
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock

The F/m Ultrashort TIPS Fund is a passively-managed exchange-traded fund (“ETF”) that seeks investment results, before fees and expenses, that correspond generally to the price and yield performance of the Bloomberg U.S. Ultrashort TIPS 1-13 Months Total Return Unhedged USD Index (I39232US) (“Underlying Index”), which measures the performance of U.S. Treasury Inflation-Protected Securities (“TIPS”) with maturities from 1 month up to (but not including) 13 months. TIPS are income-generating instruments whose interest and principal payments are adjusted for inflation. The inflation adjustment, which is typically applied monthly to the principal of the bond, follows a designated inflation index, the non-seasonally adjusted Consumer Price Index for All Urban Consumers (“CPI-U”), and TIPS’ principal payments are adjusted according to changes in the CPI-U. A fixed coupon rate is applied to the inflation-adjusted principal so that, as inflation rises, both the principal value and the interest payments increase. This can provide a hedge against inflation, as it helps preserve the purchasing power of an investment. Because of this inflation adjustment feature, inflation-protected bonds typically have lower yields than conventional fixed-rate bonds. Under normal market conditions, F/m Investments LLC (the “Adviser”) seeks to achieve the Fund’s investment objective by investing at least 80% of the Fund’s net assets (plus any borrowings for investment purposes) in TIPS with maturities of 1-13 months.

 

The Adviser uses a representative sampling indexing strategy in seeking to achieve the Fund’s investment objective. Under normal market conditions, the Fund invests substantially all of its assets in the securities comprising the Underlying Index and in securities that the Adviser determines to have economic characteristics that are substantially identical to the economic characteristics of the securities that comprise the Underlying Index, including, but not limited to, bonds that are capital-indexed and linked to a commonly used domestic inflation index.

 

In seeking to track the Underlying Index, the Fund may invest in securities that are not included in the Underlying Index, cash and cash equivalents and/or money market instruments, such as repurchase agreements and money market funds. The Fund is “non-diversified,” which means it may invest a greater percentage of its assets in the securities of a single issuer than a “diversified” fund.

 

The Underlying Index

 

The Underlying Index was incepted in January 2025, with history back to January 1, 2015, by Bloomberg Finance LP (the “Index Provider”). The Underlying Index is composed of equally weighted sub-components that have a remaining maturity from one (1) month up to (but not including) thirteen (13) months (e.g., 1-2 month maturities, 2-3 maturities, etc.). Federal Reserve holdings of TIPS are excluded from the face amount outstanding of each bond in the Underlying Index.

 

The Underlying Index has a minimum liquidity requirement of $500M USD par amount outstanding (not adjusted for index duration). The bonds included in the Underlying Index are capital-indexed and linked to a commonly used domestic inflation index. Principal and interest are inflation-linked and denominated in U.S. dollars. The bonds are rated investment grade (Baa3/BBB-/BBB- or higher) using the middle rating of Moody’s® Investors Service, Inc.(“Moody’s”), Fitch Ratings, Inc. (“Fitch”) and Standard & Poor’s® Financial Services LLC (“S&P”); when a rating from only two agencies is available, the lower is used; when only one agency rates a bond, that rating is used. In cases where explicit bond level ratings are not available, the Index Provider may use other sources to classify securities by credit quality.

 

The Underlying Index is rebalanced by the Index Provider on the last business day of each month. The Underlying Index is calculated and administered by the Index Provider, which is not affiliated with the Fund or the Adviser. The Index Provider calculates the Underlying Index and Parent Index on a total return basis.

 

Additional information regarding the Underlying Index, including its value, is available at https://www.bloomberg.com/professional/products/indices/fixed-income/.

 

The Fund may invest in securities of other affiliated and unaffiliated ETFs registered under the Investment Company Act of 1940, as amended, that invest primarily in Fund eligible investments (collectively, “Underlying Funds”) to the extent permitted by applicable law and subject to certain restrictions.

 

The Fund may also seek to increase its income by lending securities. These loans will be secured by collateral (consisting of cash, U.S. government securities, or irrevocable letters of credit) maintained in an amount equal to at least 100% of the market value, determined daily, of the loaned securities. Cash collateral received by the Fund in connection with its lending of portfolio securities will be invested in short-term investments, including money market funds.

 

The F/m Ultrashort TIPS Fund has elected to qualify each year for treatment as a regulated investment company (“RIC”) under Subchapter M of Subtitle A, Chapter 1, of the Internal Revenue Code of 1986, as amended (the “Code”).
Risk [Heading] rr_RiskHeading Principal Investment Risks
Bar Chart and Performance Table [Heading] rr_BarChartAndPerformanceTableHeading Performance Information
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock

Performance information for the F/m Ultrashort TIPS Fund is not included because the Fund had not commenced operations prior to the date of this Prospectus. Performance information will be included once the Fund has at least one calendar year of performance. Updated performance information will be available on the Fund’s website at www.ustreasuryetf.com.
Performance One Year or Less [Text] rr_PerformanceOneYearOrLess Performance information will be included once the Fund has at least one calendar year of performance.
Performance Availability Website Address [Text] rr_PerformanceAvailabilityWebSiteAddress www.ustreasuryetf.com
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Risk Lose Money [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock As with any investment, you could lose all or part of your investment in the F/m Ultrashort TIPS Fund and the Fund’s performance could trail that of other investments.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Affiliated Fund Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Affiliated Fund Risk. Affiliated fund risk is the risk that the Adviser may select investments for the Fund based on its own financial interests or other business considerations rather than the Fund’s interests. The Adviser may be subject to potential conflicts of interest in selecting the Underlying Funds because the Underlying Funds pay an advisory fee to the Adviser based on their assets, the fees paid to the Adviser by some affiliated Underlying Funds may be higher than other Underlying Funds or the Underlying Funds may be in need of assets to enhance their appeal to other investors, liquidity and trading and/or to enable them to carry out their investment strategies. However, the Adviser is a fiduciary to the Fund and is legally obligated to act in the Fund’s best interest when selecting Underlying Funds.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Asset Class Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Asset Class Risk. Securities and other assets in the Fund’s portfolio may underperform in comparison to the general financial markets, a particular financial market, or other asset classes.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Concentration Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Concentration Risk. The Fund may be susceptible to an increased risk of loss, including losses due to adverse events that affect the Fund’s investments more than the market as a whole, to the extent that the Fund’s investments are concentrated in a particular issue, issuer or issuers, country, market segment, or asset class.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Cyber Security Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Cyber Security Risk. Cyber security risk is the risk of an unauthorized breach and access to the Fund’s assets, Fund or customer data (including private shareholder information), or proprietary information, or the risk of an incident occurring that causes the Fund, the Adviser, custodian, transfer agent, distributor and other service providers and financial intermediaries to suffer data breaches, data corruption or lose operational functionality or prevent the Fund’s investors from purchasing, redeeming or exchanging shares or receiving distributions. While the Fund and Adviser have established business continuity plans and risk management systems seeking to address system breaches or failures, there are inherent limitations in such plans and systems. Further, the Fund cannot control the cybersecurity plans and systems of the Fund’s Index Provider and other service providers, market makers, or issuers of securities in which the Fund invests. The Fund and the Adviser have limited ability to prevent or mitigate cyber security incidents affecting third-party service providers, and such third-party service providers may have limited indemnification obligations to the Fund or the Adviser. Successful cyber-attacks or other cyber-failures or events affecting the Fund or its service providers may adversely impact and cause financial losses to the Fund or its shareholders. Issuers of securities in which the Fund invests are also subject to cyber security risks, and the value of these securities could decline if the issuers experience cyberattacks or other cyber-failures.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Duration Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Duration Risk. Duration is a measure of the price sensitivity of a debt security or portfolio to interest rate changes. Duration risk is the risk that longer-duration debt securities will be more volatile and thus more likely to decline in price, and to a greater extent, in a rising interest rate environment than shorter-duration debt securities.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | ETF Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●ETF Risk. The Fund is an ETF, and, as a result of an ETF’s structure, it is exposed to the following risks:

 

●Authorized Participants, Market Makers and Liquidity Providers Concentration Risk. Only an authorized participant (“AP”) may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of financial institutions that are institutional investors and may act as APs. In addition, there may be a limited number of market makers and/or liquidity providers in the marketplace. To the extent either of the following events occur, Fund Shares may trade at a material discount to NAV and possibly face delisting: (i) APs exit the business or otherwise become unable to process creation and/or redemption orders and no other APs step forward to perform these services, or (ii) market makers and/or liquidity providers exit the business or significantly reduce their business activities and no other entities step forward to perform their functions. These events, among others, may lead to the Fund Shares trading at a premium or discount to NAV. Thus, you may pay more (or less) than the NAV when you buy Shares of the Fund in the secondary market, and you may receive less (or more) than NAV when you sell those Shares in the secondary market. A diminished market for an ETF’s Shares substantially increases the risk that a shareholder may pay considerably more or receive significantly less than the underlying value of the ETF Shares bought or sold. In periods of market volatility, APs, market makers and/or liquidity providers may be less willing to transact in Fund Shares.

 

●Secondary Market Trading Risk. Although the Fund’s Shares are listed on a national securities exchange, The Nasdaq Stock Market, LLC (the “Exchange”), and may be traded on U.S. exchanges other than the Exchange, there can be no assurance that an active or liquid trading market for them will develop or be maintained. In addition, trading in Shares on the Exchange may be halted. During periods of market stress, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount). This risk is heightened in times of market volatility or periods of steep market declines.
  
●Shares May Trade at Prices Other Than NAV Risk. As with all ETFs, Fund Shares may be bought and sold in the secondary market at market prices. Although it is expected that the market price of Shares will approximate the Fund’s NAV, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount). This risk is heightened in times of market volatility or periods of steep market declines.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Fixed Income Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Fixed-Income Market Risk. The market value of a fixed-income security may decline due to general market conditions that are not specifically related to a particular issuer, such as real or perceived adverse economic conditions, changes in the outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. The fixed-income securities market can be susceptible to increases in volatility and decreases in liquidity. Liquidity can decline unpredictably in response to overall economic conditions or credit tightening. Increases in volatility and decreases in liquidity may be caused by a rise in interest rates (or the expectation of a rise in interest rates). An unexpected increase in Fund redemption requests, including requests from shareholders who may own a significant percentage of the Fund’s Shares, which may be triggered by market turmoil or an increase in interest rates, could cause the Fund to sell its holdings at a loss or at undesirable prices and adversely affect the Fund’s Share price and increase the Fund’s liquidity risk, expenses and/or taxable distributions.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | High Portfolio Turnover Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●High Portfolio Turnover Risk. The Fund may incur relatively high portfolio turnover. The active and frequent trading of the Fund’s portfolio securities may result in increased transaction costs to the Fund, including brokerage commissions, dealer mark-ups and other transaction costs, which could reduce the Fund’s return.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Income Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Income Risk. The Fund’s income may decline if interest rates fall. This decline in income can occur because the Fund may subsequently invest in lower yielding bonds as bonds in its portfolio mature, are near maturity, or are called, or the Fund otherwise needs to purchase additional bonds.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Index Related Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Index-Related Risk. There is no guarantee that the Fund’s investment results will have a high degree of correlation to those of the Underlying Index or that the Fund will achieve its investment objective. Market disruptions and regulatory restrictions could have an adverse effect on the Fund’s ability to adjust its exposure to the required levels in order to track the Underlying Index. The Index Provider may rely on various sources of information to assess the criteria of components of the Underlying Index, including information that may be based on assumptions and estimates. Neither the Fund nor the Adviser can offer assurances that the Index Provider’s methodology or sources of information will provide an accurate assessment of included components. Errors in index data, index computations or the construction of the Underlying Index in accordance with its methodology may occur from time to time and may not be identified and corrected by the Index Provider for a period of time or at all, which may have an adverse impact on the Fund and its shareholders. Unusual market conditions or other unforeseen circumstances (such as natural disasters, political unrest or war) may impact the Index Provider or a third-party Provider and may cause the Index Provider to postpone a scheduled rebalance, which could cause the Underlying Index to vary from its normal or expected composition.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Inflation Indexed Bonds Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Inflation-Indexed Bonds Risk. The principal value of an investment is not protected or otherwise guaranteed by virtue of the Fund’s investments in inflation-indexed bonds. Inflation-indexed bonds are fixed-income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of U.S. Treasury inflation-indexed bonds. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal value. The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Short-term increases in inflation may lead to a decline in value. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity. Periodic adjustments for inflation to the principal amount of an inflation-indexed bond may give rise to original issue discount, which will be includable in the Fund’s gross income. Due to original issue discount, the Fund may be required to make annual distributions to shareholders that exceed the cash received, which may cause the Fund to liquidate certain investments when it is not advantageous to do so. Also, if the principal value of an inflation-indexed bond is adjusted downward due to deflation, amounts previously distributed in the taxable year may be characterized in some circumstances as a return of capital.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Inflation Linked Securities [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Inflation-Linked Securities. In general, the value of an inflation-linked security, including TIPS, will typically decrease when real interest rates (nominal interest rates reduced by the expected impact of inflation) increase and increase when real interest rates decrease. When inflation is negative or concerns over inflation are low, the value and income of inflation-linked securities could fall and result in losses for the Fund and during periods of very low inflation, the yield on an inflation-linked security may be negative. Conversely, during sustained periods of high inflation, the Fund’s yield should increase, which may not be repeated. Funds that invest heavily in inflation-linked securities do not always move in lockstep with inflation because they do not necessarily buy inflation-linked securities when they are originally issued or hold them until maturity. In addition, the accrual of inflation adjustments on the Fund’s holdings may significantly impact the current level of dividends actually paid to shareholders. Changes in inflation rates and/or interest rates may cause the Fund’s yield to vary substantially over time.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Interest Rate Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Interest Rate Risk. Interest rate risk is the risk of losses attributable to changes in interest rates. In general, if prevailing interest rates rise, the values of debt instruments tend to fall, and if interest rates fall, the values of debt instruments tend to rise. Changes in the value of a debt instrument usually will not affect the amount of income the Fund receives from it but will generally affect the value of your investment in the Fund. Changes in interest rates may also affect the liquidity of the Fund’s investments in debt instruments. In general, the longer the maturity or duration of a debt instrument, the greater its sensitivity to changes in interest rates. The Fund is subject to the risk that the income generated by its investments may not keep pace with inflation. Actions by governments and central banking authorities can result in increases or decreases in interest rates, which may negatively affect the value of debt instruments held by the Fund and have a negative impact on the Fund’s performance and NAV. Rising interest rates may prompt redemptions from the Fund, which may force the Fund to sell investments at a time when it is not advantageous to do so, which could result in losses. During periods of very low or negative interest rates, the Fund may be unable to maintain positive returns or pay dividends to Fund shareholders. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, result in heightened market volatility and detract from the Fund’s performance to the extent the Fund is exposed to such interest rates. Additionally, under certain market conditions in which interest rates are low and the market prices for portfolio securities have increased, the Fund may have a very low or even negative yield. A low or negative yield would cause the Fund to lose money in certain conditions and over certain time periods. An increase in interest rates will generally cause the value of securities held by the Fund to decline, may lead to heightened volatility in the fixed-income markets and may adversely affect the liquidity of certain fixed-income investments, including those held by the Fund. The historically low-interest rate environment in recent years heightens the risks associated with rising interest rates.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Management Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Management Risk. As the Fund’s portfolio will not typically replicate the Underlying Index fully, it is subject to the risk that the Adviser’s investment strategy may not produce the intended results. The Adviser’s use of a representative sampling indexing strategy to manage the Fund’s portfolio may subject the Fund to an increased risk of tracking error, in that the securities selected in aggregate for the Fund’s portfolio may not have an investment profile similar to those of the Underlying Index.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Market Risk. The trading prices of securities and other instruments fluctuate in response to a variety of factors. The Fund’s NAV and market price may fluctuate significantly in response to these and other factors including economic, political, financial, public health crises (such as epidemics or pandemics), war, acts of terrorism, recessions or other disruptive events (whether real, expected or perceived) in the local, regional or global markets. These factors could have a significant impact on the Fund and its investments and could result in increased premiums or discounts to the Fund’s NAV. As a result, an investor could lose money over short periods due to short-term market movements or long periods of time during prolonged market downturns.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Market Trading Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Market Trading Risk. The Fund faces numerous market trading risks, including the potential lack of an active market for the Shares, losses from trading in secondary markets, and disruption in the creation/redemption process of the Fund. In stressed market conditions, the market for Shares may become less liquid in response to deteriorating liquidity in the markets for the Fund’s portfolio holdings, which may cause a variance in the market price of Shares and their underlying NAV. In addition, an exchange or market may issue trading halts on specific securities or financial instruments. As a result, the ability to trade certain securities or financial instruments may be restricted, which may disrupt the Fund’s creation/redemption process, potentially affect the price at which Shares trade in the secondary market, and/or result in the Fund being unable to trade certain securities or financial instruments at all. In these circumstances, the Fund may be unable to rebalance its portfolio, may be unable to accurately price its investments and/or may incur substantial trading losses. Any of these factors may lead to the Shares trading at a premium or discount to the Fund’s NAV.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | New Fund Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●New Fund Risk. The Fund is a newly organized management investment company with a limited operating history. In addition, there can be no assurance that the Fund will grow to, or maintain, an economically viable size, in which case the Board of Directors (the “Board”) of The RBB Fund, Inc. (the “Company”) may determine to liquidate the Fund.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Operational Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Operational Risk. The Fund is exposed to operational risks arising from a number of factors, including, but not limited to, human error, processing and communication errors, errors of the Fund’s service providers, counterparties, or other third parties, failed or inadequate processes or technology or systems failures. The Fund and the Adviser seek to reduce these operational risks through controls and procedures. However, these measures do not address every possible risk and may be inadequate to address significant operational risks.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Passive Investment Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Passive Investment Risk. Although the Fund is permitted to invest up to 100% of its assets in money market instruments for temporary defensive or liquidity purposes, the Adviser generally does not attempt to invest the Fund’s assets in defensive positions.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Reinvestment Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Reinvestment Risk. Reinvestment risk is the risk that income from the Fund’s portfolio will decline if and when the Fund reinvests the proceeds from the disposition of its portfolio securities at market interest rates that are below the portfolio’s current earnings rate. A decline in income could negatively affect the market price of the Shares.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Risk Of Investing In The United States [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Risk of Investing in the United States. Certain changes in the United States economy, such as when the economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | Securities Lending Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Securities Lending Risk. The Fund may engage in securities lending (i.e., lend portfolio securities to institutions, such as certain broker dealers). Securities lending involves the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. These events could also trigger adverse tax consequences for the Fund. The Fund could also experience a loss or delay in the recovery of its securities if the borrowing institution breaches its agreement with the Fund.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | US Treasury Obligations Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●U.S. Treasury Obligations Risk. While U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. Government, such securities are nonetheless subject to credit risk (i.e., the risk that the U.S. Government may be, or be perceived to be, unable or unwilling to honor its financial obligations, such as making payments). Securities issued or guaranteed by federal agencies or authorities and U.S. Government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. Government. U.S. Treasury obligations may differ from other securities in their interest rates, maturities, times of issuance and other characteristics and may provide relatively lower returns than those of other securities. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of the Fund’s U.S. Treasury obligations to decline.
F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF | F/m Ultrashort Treasury Inflation-Protected Security (TIPS) ETF Shares  
Prospectus [Line Items] rr_ProspectusLineItems  
Trading Symbol dei_TradingSymbol RBIL
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.25%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets none [1]
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.25%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 26
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 $ 80
F/m Yield Curve Steepening Strategy ETF  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk/Return [Heading] rr_RiskReturnHeading SUMMARY SECTION – F/m Yield Curve Steepening Strategy ETF (USTP)
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock

The investment objective of the F/m Yield Curve Steepening Strategy ETF (the “F/m Yield Curve Steepening Fund” or the “Fund”) is to seek to implement a steepener yield curve strategy that is designed to benefit from the widening spread between short-term and long-term U.S. Treasury yields that typically occurs when shorter-maturity rates fall faster than longer-maturity rates, or when longer-maturity rates rise relative to shorter-maturity rates.
Expense [Heading] rr_ExpenseHeading Fees and Expenses
Expense Narrative [Text Block] rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the F/m Yield Curve Steepening Fund (“Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Operating Expenses Caption [Text] rr_OperatingExpensesCaption Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
Portfolio Turnover [Heading] rr_PortfolioTurnoverHeading Portfolio Turnover
Portfolio Turnover [Text Block] rr_PortfolioTurnoverTextBlock

The F/m Yield Curve Steepening 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. No portfolio turnover rate is provided for the Fund because the Fund had not commenced operations prior to the date of this Prospectus.
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This Example is intended to help you compare the cost of investing in the F/m Yield Curve Steepening Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then hold or redeem all of your Shares at the end of those periods. The Example also assumes that: (1) your investment has a 5% return each year, and (2) the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading] rr_StrategyHeading Principal Investment Strategies
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock

The F/m Yield Curve Steepening Fund is an actively-managed exchange-traded fund (“ETF”) that seeks to implement a steepener yield curve strategy that is designed to benefit from the widening spread between short-term and long-term U.S. Treasury yields that typically occurs when shorter-maturity rates fall faster than longer-maturity rates, or when longer-maturity rates rise relative to shorter-maturity rates.

 

Under normal market conditions, F/m Investments LLC (the “Adviser”) seeks to achieve the Fund’s investment objective by investing at least 80% of the Fund’s net assets (plus any borrowings for investment purposes) in a combination of long and short positions in U.S. Treasury securities or derivatives, such as U.S. Treasury futures, interest rate swaps, and options, to express a view on the shape of the yield curve. Specifically, the Fund may:

 

●Take short positions in longer-duration U.S. Treasury securities or derivatives or affiliated ETFs to gain exposure to rising yields at the long end of the curve.

 

●Take long positions in shorter-duration U.S. Treasury securities or derivatives or affiliated ETFs to gain exposure to falling yields at the short end of the curve.

The Adviser actively manages the Fund’s positions based on market conditions, macroeconomic trends, and interest rate forecasts. The Fund’s portfolio is constructed and rebalanced periodically to maintain exposure aligned with the yield steepener objective, considering factors such as economic data, Federal Reserve policy, and global interest rate dynamics.

 

The Fund may also allocate a portion of its assets to cash, cash equivalents, or high-quality short-term instruments for liquidity and collateral purposes. The Fund does not seek to maintain a specific duration target, as its primary focus is on the relative movement between segments of the yield curve.

 

The Fund may enter into reverse repurchase agreements in amounts not exceeding one-third of the Fund’s total assets (including the amount borrowed). The Fund may invest in securities of other affiliated and unaffiliated ETFs registered under the Investment Company Act of 1940, as amended, that invest primarily in Fund eligible investments (collectively, “Underlying Funds”) to the extent permitted by applicable law and subject to certain restrictions.

 

The Fund may also seek to increase its income by lending securities. These loans will be secured by collateral (consisting of cash, U.S. government securities, or irrevocable letters of credit) maintained in an amount equal to at least 100% of the market value, determined daily, of the loaned securities. Cash collateral received by the Fund in connection with its lending of portfolio securities will be invested in short-term investments, including money market funds.

 

The F/m Yield Curve Steepening Fund has elected to qualify each year for treatment as a regulated investment company (“RIC”) under Subchapter M of Subtitle A, Chapter 1, of the Internal Revenue Code of 1986, as amended (the “Code”).
Risk [Heading] rr_RiskHeading Principal Investment Risks
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock

Performance Information: Performance information for the F/m Yield Curve Steepening Fund is not included because the Fund had not commenced operations prior to the date of this Prospectus. Performance information will be included once the Fund has at least one calendar year of performance. Updated performance information will be available on the Fund’s website at www.fminvest.com.
Performance One Year or Less [Text] rr_PerformanceOneYearOrLess Performance information will be included once the Fund has at least one calendar year of performance.
Performance Availability Website Address [Text] rr_PerformanceAvailabilityWebSiteAddress www.fminvest.com
F/m Yield Curve Steepening Strategy ETF | Risk Lose Money [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock As a result, you may lose money on your investment in the Fund, and there can be no assurance that the Fund will achieve its investment objective.
F/m Yield Curve Steepening Strategy ETF | Affiliated Fund Risk [Member]  
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●Affiliated Fund Risk. Affiliated fund risk is the risk that the Adviser may select investments for the Fund based on its own financial interests or other business considerations rather than the Fund’s interests. The Adviser may be subject to potential conflicts of interest in selecting the Underlying Funds because the Underlying Funds pay an advisory fee to the Adviser based on their assets, the fees paid to the Adviser by some affiliated Underlying Funds may be higher than other Underlying Funds or the Underlying Funds may be in need of assets to enhance their appeal to other investors, liquidity and trading and/or to enable them to carry out their investment strategies. However, the Adviser is a fiduciary to the Fund and is legally obligated to act in the Fund’s best interest when selecting Underlying Funds.
F/m Yield Curve Steepening Strategy ETF | Asset Class Risk [Member]  
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●Asset Class Risk. Securities and other assets in the Fund’s portfolio may underperform in comparison to the general financial markets, a particular financial market, or other asset classes.
F/m Yield Curve Steepening Strategy ETF | Concentration Risk [Member]  
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●Concentration Risk. The Fund may be susceptible to an increased risk of loss, including losses due to adverse events that affect the Fund’s investments more than the market as a whole, to the extent that the Fund’s investments are concentrated in a particular issue, issuer or issuers, country, market segment, or asset class.
F/m Yield Curve Steepening Strategy ETF | Cyber Security Risk [Member]  
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●Cyber Security Risk. Cyber security risk is the risk of an unauthorized breach and access to the Fund’s assets, Fund or customer data (including private shareholder information), or proprietary information, or the risk of an incident occurring that causes the Fund, the Adviser, custodian, transfer agent, distributor and other service providers and financial intermediaries to suffer data breaches, data corruption or lose operational functionality or prevent the Fund’s investors from purchasing, redeeming or exchanging shares or receiving distributions. While the Fund and the Adviser have established business continuity plans and risk management systems seeking to address system breaches or failures, there are inherent limitations in such plans and systems. Further, the Fund cannot control the cybersecurity plans and systems of the Fund’s service providers, market makers, or issuers of securities in which the Fund invests. The Fund and the Adviser have limited ability to prevent or mitigate cyber security incidents affecting third-party service providers, and such third-party service providers may have limited indemnification obligations to the Fund or the Adviser. Successful cyber-attacks or other cyber-failures or events affecting the Fund or its service providers may adversely impact and cause financial losses to the Fund or its shareholders. Issuers of securities in which the Fund invests are also subject to cyber security risks, and the value of these securities could decline if the issuers experience cyber-attacks or other cyber-failures.
F/m Yield Curve Steepening Strategy ETF | Duration Risk [Member]  
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●Duration Risk. Duration is a measure of the price sensitivity of a debt security or portfolio to interest rate changes. Duration risk is the risk that longer-duration debt securities will be more volatile and thus more likely to decline in price, and to a greater extent, in a rising interest rate environment than shorter-duration debt securities.
F/m Yield Curve Steepening Strategy ETF | ETF Risk [Member]  
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●ETF Risk. The Fund is an ETF, and, as a result of an ETF’s structure, it is exposed to the following risks:

 

●Authorized Participants, Market Makers and Liquidity Providers Concentration Risk. Only an authorized participant (“AP”) may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of financial institutions that are institutional investors and may act as APs. In addition, there may be a limited number of market makers and/or liquidity providers in the marketplace. To the extent either of the following events occur, Note Fund Shares may trade at a material discount to net asset value (“NAV”) and possibly face delisting: (i) APs exit the business or otherwise become unable to process creation and/or redemption orders and no other APs step forward to perform these services, or (ii) market makers and/or liquidity providers exit the business or significantly reduce their business activities and no other entities step forward to perform their functions. These events, among others, may lead to the Fund Shares trading at a premium or discount to NAV. Thus, you may pay more (or less) than the NAV when you buy Shares of the Fund in the secondary market, and you may receive less (or more) than NAV when you sell those Shares in the secondary market. A diminished market for an ETF’s shares substantially increases the risk that a shareholder may pay considerably more or receive significantly less than the underlying value of the ETF shares bought or sold. In periods of market volatility, APs, market makers and/or liquidity providers may be less willing to transact in Fund Shares.

 

●Secondary Market Trading Risk. Although Shares are listed on a national securities exchange (the “Exchange”), and may be traded on U.S. exchanges other than the Exchange, there can be no assurance that an active or liquid trading market for them will develop or be maintained. In addition, trading in Shares on the Exchange may be halted. During periods of market stress, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount). This risk is heightened in times of market volatility or periods of steep market declines.

 

●Shares May Trade at Prices Other Than NAV Risk. As with all ETFs, Shares may be bought and sold in the secondary market at market prices. Shares trade on a stock exchange at prices at, above, or below the Fund’s most recent NAV. The Fund’s NAV is calculated at the end of each business day and fluctuates with changes in the market value of the Fund’s holdings. The trading price of the Shares fluctuates continuously throughout trading hours on the exchange, based on both the relative market supply of, and demand for, the Shares and the underlying value of the Fund’s portfolio holdings. As a result, the trading prices of the Shares may deviate from the Fund’s NAV. Although it is expected that the market price of Shares will approximate the Fund’s NAV, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount). This risk is heightened in times of market volatility or periods of steep market declines. Any of these factors, among others, may lead to the Shares trading at a premium or discount to NAV.
F/m Yield Curve Steepening Strategy ETF | Fixed Income Market Risk [Member]  
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●Fixed-Income Market Risk. When the Fund invests in fixed income securities, the value of your investment in the Fund will fluctuate with changes in interest rates. Typically, a rise in interest rates causes a decline in the value of fixed income securities owned by the Fund. In general, the market price of fixed income securities with longer maturities or duration will increase or decrease more in response to changes in interest rates than shorter-term securities. Other risk factors include credit risk (the debtor may default), extension risk (an issuer may exercise its right to repay principal on a fixed rate obligation held by the Fund later than expected), and prepayment risk (the debtor may pay its obligation early, reducing the amount of interest payments). These risks could affect the value of a particular investment by the Fund, possibly causing the Fund’s share price and total return to be reduced and fluctuate more than other types of investments.
F/m Yield Curve Steepening Strategy ETF | High Portfolio Turnover Risk [Member]  
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●High Portfolio Turnover Risk. The Fund may incur relatively high portfolio turnover. The active and frequent trading of the Fund’s portfolio securities may result in increased transaction costs to the Fund, including brokerage commissions, dealer mark-ups and other transaction costs, which could reduce the Fund’s return.
F/m Yield Curve Steepening Strategy ETF | Income Risk [Member]  
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●Income Risk. The Fund’s income may decline if interest rates fall. This decline in income can occur because the Fund may subsequently invest in lower yielding bonds as bonds in its portfolio mature, are near maturity or are called, or the Fund otherwise needs to purchase additional bonds.
F/m Yield Curve Steepening Strategy ETF | Interest Rate Risk [Member]  
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●Interest Rate Risk. Interest rate risk is the risk of losses attributable to changes in interest rates. In general, if prevailing interest rates rise, the values of debt instruments tend to fall, and if interest rates fall, the values of debt instruments tend to rise. Changes in the value of a debt instrument usually will not affect the amount of income the Fund receives from it but will generally affect the value of your investment in the Fund. Changes in interest rates may also affect the liquidity of the Fund’s investments in debt instruments. In general, the longer the maturity or duration of a debt instrument, the greater its sensitivity to changes in interest rates. The Fund is subject to the risk that the income generated by its investments may not keep pace with inflation. Actions by governments and central banking authorities can result in increases or decreases in interest rates, which may negatively affect the value of debt instruments held by the Fund and have a negative impact on the Fund’s performance and NAV. Rising interest rates may prompt redemptions from the Fund, which may force the Fund to sell investments at a time when it is not advantageous to do so, which could result in losses. During periods of very low or negative interest rates, the Fund may be unable to maintain positive returns or pay dividends to Fund shareholders. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, result in heightened market volatility and detract from the Fund’s performance to the extent the Fund is exposed to such interest rates. Additionally, under certain market conditions in which interest rates are low and the market prices for portfolio securities have increased, the Fund may have a very low or even negative yield. A low or negative yield would cause the Fund to lose money in certain conditions and over certain time periods. An increase in interest rates will generally cause the value of securities held by the Fund to decline, may lead to heightened volatility in the fixed-income markets and may adversely affect the liquidity of certain fixed-income investments, including those held by the Fund. The historically low-interest rate environment in recent years heightens the risks associated with rising interest rates.
F/m Yield Curve Steepening Strategy ETF | Market Risk [Member]  
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●Market Risk. The trading prices of securities and other instruments fluctuate in response to a variety of factors. The Fund’s NAV and market price may fluctuate significantly in response to these and other factors including economic, political, financial, public health crises (such as epidemics or pandemics), war, acts of terrorism, recessions or other disruptive events (whether real, expected or perceived) in the local, regional or and global markets. These factors could have a significant impact on the Fund and its investments and could result in increased premiums or discounts to the Fund’s NAV. As a result, an investor could lose money over short periods due to short-term market movements or long periods of time during prolonged market downturns.
F/m Yield Curve Steepening Strategy ETF | Market Trading Risk [Member]  
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●Market Trading Risk. The Fund faces numerous market trading risks, including the potential lack of an active market for the Shares, losses from trading in secondary markets, and disruption in the creation/redemption process of the Fund. In stressed market conditions, the market for Shares may become less liquid in response to deteriorating liquidity in the markets for the Fund’s portfolio holdings, which may cause a variance in the market price of Shares and their underlying NAV. In addition, an exchange or market may issue trading halts on specific securities or financial instruments. As a result, the ability to trade certain securities or financial instruments may be restricted, which may disrupt the Fund’s creation/redemption process, potentially affect the price at which Shares trade in the secondary market, and/or result in the Fund being unable to trade certain securities or financial instruments at all. In these circumstances, the Fund may be unable to rebalance its portfolio, may be unable to accurately price its investments and/or may incur substantial trading losses. Any of these factors may lead to the Shares trading at a premium or discount to the Fund’s NAV.
F/m Yield Curve Steepening Strategy ETF | New Fund Risk [Member]  
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●New Fund Risk. The Fund is a newly organized management investment company with a limited operating history. In addition, there can be no assurance that the Fund will grow to, or maintain, an economically viable size, in which case the Board of Directors (the “Board”) of The RBB Fund, Inc. (the “Company”) may determine to liquidate the Fund.
F/m Yield Curve Steepening Strategy ETF | Operational Risk [Member]  
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●Operational Risk. The Fund is exposed to operational risks arising from a number of factors, including, but not limited to, human error, processing and communication errors, errors of the Fund’s service providers, counterparties or other third parties, failed or inadequate processes and technology or systems failures. The Fund and the Adviser seek to reduce these operational risks through controls and procedures. However, these measures do not address every possible risk and may be inadequate to address significant operational risks.
F/m Yield Curve Steepening Strategy ETF | Reinvestment Risk [Member]  
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●Reinvestment Risk. Reinvestment risk is the risk that income from the Fund’s portfolio will decline if and when the Fund reinvests the proceeds from the disposition of its portfolio securities at market interest rates that are below the portfolio’s current earnings rate. A decline in income could negatively affect the market price of the Shares.
F/m Yield Curve Steepening Strategy ETF | Risk Of Investing In The United States [Member]  
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●Risk of Investing in the United States. Certain changes in the United States economy, such as when the economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.
F/m Yield Curve Steepening Strategy ETF | Securities Lending Risk [Member]  
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●Securities Lending Risk. The Fund may engage in securities lending (i.e., lend portfolio securities to institutions, such as certain broker dealers). Securities lending involves the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. These events could also trigger adverse tax consequences for the Fund. The Fund could also experience a loss or delay in the recovery of its securities if the borrowing institution breaches its agreement with the Fund.
F/m Yield Curve Steepening Strategy ETF | US Treasury Obligations Risk [Member]  
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●U.S. Treasury Obligations Risk. While U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. Government, such securities are nonetheless subject to credit risk (i.e., the risk that the U.S. Government may be, or be perceived to be, unable or unwilling to honor its financial obligations, such as making payments). Securities issued or guaranteed by federal agencies or authorities and U.S. Government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. Government. U.S. Treasury obligations may differ from other securities in their interest rates, maturities, times of issuance and other characteristics and may provide relatively lower returns than those of other securities. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of the Fund’s U.S. Treasury obligations to decline.
F/m Yield Curve Steepening Strategy ETF | Active Management Risk [Member]  
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●Active Management Risk. The Fund is actively managed using proprietary investment strategies and processes. There can be no guarantee that these strategies and processes will be successful or that the Fund will achieve its investment objective.
F/m Yield Curve Steepening Strategy ETF | Cash or Cash Equivalents Risk [Member]  
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●Cash or Cash Equivalents Risk. At any time, the Fund may have significant investments in cash or cash equivalents. When a substantial portion of a portfolio is held in cash or cash equivalents, there is the risk that the value of the cash account, including interest, will not keep pace with inflation, thus reducing purchasing power over time. Additionally, in rising markets, holding cash or cash equivalents may adversely affect the Fund’s performance and the Fund may not achieve its investment objective.
F/m Yield Curve Steepening Strategy ETF | Counterparty Risk [Member]  
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●Counterparty Risk. Counterparty risk is the risk that a counterparty to a swap contract or other similar investment instrument may default on its payment obligation to the Fund. Such a default may cause the value of an investment in the Fund to decrease.
F/m Yield Curve Steepening Strategy ETF | Derivatives Risk [Member]  
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●Derivatives Risk. A Fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. These risks include (i) the risk that the counterparty to a derivative transaction may not fulfill its contractual obligations; (ii) risk of mispricing or improper valuation; and (iii) the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. Derivative prices are highly volatile and may fluctuate substantially during a short period of time. Such prices are influenced by numerous factors that affect the markets, including, but not limited to: changing supply and demand relationships; government programs and policies; national and international political and economic events, changes in interest rates, inflation and deflation and changes in supply and demand relationships. Trading derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities.
F/m Yield Curve Steepening Strategy ETF | Early Close Trading Halt Risk [Member]  
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●Early Close/Trading Halt Risk. An exchange or market may close or issue trading halts on specific securities, or the ability to buy or sell certain securities or financial instruments may be restricted, which may prevent a Fund from buying or selling certain securities or financial instruments. In these circumstances, a Fund may be unable to rebalance its portfolio, may be unable to accurately price its investments and may incur substantial trading losses.
F/m Yield Curve Steepening Strategy ETF | Futures Risk [Member]  
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●Futures Risk. Futures are standardized, exchange-traded contracts that obligate a purchaser to take delivery, and a seller to make delivery, of a specific amount of an asset at a specified future date at a specified price. The primary risks associated with the use of futures contracts and options are: (a) the imperfect correlation between the change in market value of the instruments held by the Fund and the price of the futures contract or option; (b) the possible lack of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; (c) losses caused by unanticipated market movements, which are potentially unlimited; (d) the investment adviser’s inability to predict correctly the direction of securities prices, interest rates, currency exchange rates and other economic factors; and (e) the possibility that the counterparty will default in the performance of its obligations.
F/m Yield Curve Steepening Strategy ETF | Illiquid Investments Risk [Member]  
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●Illiquid Investments Risk. The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately.
F/m Yield Curve Steepening Strategy ETF | Issuer Risk [Member]  
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●Issuer Risk. The performance of the Fund depends on the performance of individual securities or other assets to which the Fund has exposure. The value of securities or other assets may decline, or perform differently from the market as a whole, due to changes in the financial condition or credit rating of the issuer or counterparty.
F/m Yield Curve Steepening Strategy ETF | Leverage Risk [Member]  
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●Leverage Risk. Using derivatives can create leverage, which can amplify the effects of market volatility on the Fund's share price and make the Fund's returns more volatile. The use of leverage may cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The use of leverage may also cause the Fund to have higher expenses than those of other funds that do not use such techniques.
F/m Yield Curve Steepening Strategy ETF | Liquidity Risk [Member]  
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●Liquidity Risk. Certain securities held by the Fund may be difficult (or impossible) to sell at the time and at the price the Adviser would like. As a result, the Fund may have to hold these securities longer than it would like and may forego other investment opportunities. There is the possibility that the Fund may lose money or be prevented from realizing capital gains if it cannot sell a security at a particular time and price.
F/m Yield Curve Steepening Strategy ETF | Options Risk [Member]  
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●Options Risk. When the Fund purchases a call option, it receives, in return for the premium it pays, the right to buy from the writer of the option the underlying security at a specified price at any time before the option expires. The Fund purchases call options in anticipation of an increase in the market value of securities that it intends ultimately to buy. During the life of the call option, a Fund is able to buy the underlying security at the exercise price regardless of any increase in the market price of the underlying security. In order for a call option to result in a gain, the market price of the underlying security must exceed the sum of the exercise price, the premium paid, and transaction costs.
F/m Yield Curve Steepening Strategy ETF | Over the Counter Market Risk [Member]  
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●Over-the-Counter Market Risk. Securities and options traded in over-the-counter markets may trade less frequently and in limited volumes and thus exhibit more volatility and liquidity risk, and the prices paid by the Fund in over-the-counter transactions may include an undisclosed dealer markup. The Fund is also exposed to default by the over-the-counter option writer who may be unwilling or unable to perform its contractual obligations to the Fund.
F/m Yield Curve Steepening Strategy ETF | Pricing Risk [Member]  
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●Pricing Risk. If market conditions make it difficult to value some investments, the Fund may value these investments using more subjective methods, such as fair value pricing. In such cases, the value determined for an investment could be different from the value realized upon such investment’s sale. As a result, you could pay more than the market value when buying Fund Shares or receive less than the market value when selling Fund Shares.
F/m Yield Curve Steepening Strategy ETF | Rate Linked Derivatives Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Rate-Linked Derivatives Risk. The Fund’s exposure to derivatives tied to interest rates subjects the Fund to greater volatility than investments in traditional securities, such as stocks and bonds. Investing in derivatives tied to interest rates, including through options tied to the shape of the U.S. interest rate curve, can be extremely volatile. The value of such investments may fluctuate rapidly based on a variety of factors, including overall market movements; economic events and policies; changes in interest rates or inflation rates; changes in monetary and exchange control programs; war; acts of terrorism; natural disasters; and technological developments. The Fund is expected to benefit from the options it holds if long-term U.S. interest rates rise during the time period in which the Fund holds the options. However, if long-term U.S. interest rates decrease, the Fund will lose money on the options, up to the amount invested in option premiums, and underperform an otherwise identical bond fund that had not used such options. Rate-linked derivatives may lose money if interest rates change in a manner not anticipated by the Adviser. An increase in interest rates may cause the value of securities held directly or indirectly by the Fund to decline to the extent that the Fund’s hedging strategy is not effectively implemented. Even if the Fund is hedged against losses due to long-term interest rate increases linked to U.S. interest rates, outright interest rate increases may also lead to heightened volatility in the fixed-income markets and may positively affect the value of the Fund’s options while negatively impacting the Fund’s investments in U.S. Treasuries. The Fund could lose money on the options held by the Fund, and the present value of the Fund’s portfolio investments could decrease if inflation increases. These interest rate-linked options may also cause the Fund’s net asset value and returns to be more volatile and expose the Fund to increased counterparty risk. Fluctuations in the U.S. interest rate curve or the price of the options owned by the Fund could materially adversely affect an investment in the Fund. The Fund’s investments in options are not intended to mitigate duration and credit risk or other factors influencing the price of U.S. government bonds, which may have a greater impact on the bonds’ returns than interest rate risk. Moreover, to the extent that interest rate risk has been priced into the government bonds owned directly or indirectly by the Fund, the Fund could underperform other investments even during periods of rising long-term U.S. interest rates. There is no guarantee that the Fund will have positive performance even in environments of sharply rising U.S. interest rates. There is no guarantee that the Fund will be able to successfully mitigate interest rate risk.
F/m Yield Curve Steepening Strategy ETF | Rating Agencies Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Rating Agencies Risk. Ratings are not an absolute standard of quality, but rather general indicators that reflect only the view of the originating rating agencies from which an explanation of the significance of such ratings may be obtained. There is no assurance that a particular rating will continue for any given period of time or that any such rating will not be revised downward or withdrawn entirely if, in the judgment of the agency establishing the rating, circumstances so warrant. A downward revision or withdrawal of such ratings, or either of them, may have an effect on the liquidity or market price of the securities in which the Fund invests.
F/m Yield Curve Steepening Strategy ETF | Reverse Repurchase Agreements Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Reverse Repurchase Agreements Risk. Reverse repurchase agreements are a form of secured borrowing and subject the Fund to the risks associated with leverage, including exposure to potential gains and losses in excess of the amount invested, resulting in an increase in the speculative character of the Fund’s outstanding shares. Reverse repurchase agreements involve the risk that the investment return earned by the Fund (from the investment of the proceeds) will be less than the interest expense of the transaction, that the market value of the securities sold by the Fund will decline below the price the Fund is obligated to pay to repurchase the securities, and that the other party may fail to return the securities in a timely manner or at all.
F/m Yield Curve Steepening Strategy ETF | Shorting US Treasury Securities Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Shorting U.S. Treasury Securities Risk. The Fund may seek short exposure to financial instruments such as U.S. Treasury securities. There is no guarantee that the returns on the Fund’s short positions will produce positive returns and the Fund could lose money if the short positions produce negative returns. U.S. Treasury prices are highly sensitive to changes in interest rates and a decrease in yields (increase in prices) could result in significant losses for short positions. Shorting typically requires borrowing securities, which involves reliance on the availability of lenders and custodians. The failure of a counterparty to deliver the securities may impact the Fund’s execution of its strategy.
F/m Yield Curve Steepening Strategy ETF | Swap Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Swap Risk. Swaps are subject to tracking risk because they may not be perfect substitutes for the instruments they are intended to hedge or replace. Over the counter swaps are subject to counterparty default. Leverage inherent in derivatives will tend to magnify the Fund’s losses.
F/m Yield Curve Steepening Strategy ETF | Swaptions Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Swaptions Risk: A “swaption” is a contract that gives a counterparty the right (but not the obligation) to enter into a new swap agreement or to shorten, extend, cancel or otherwise modify an existing swap agreement, at some designated future time on specified terms. The Fund may purchase interest rate payer swaptions. When the Fund purchases a swaption, it risks losing only the amount of the premium it has paid should it decide to let the option expire unexercised.
F/m Yield Curve Steepening Strategy ETF | TBA Securities Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●TBA Securities Risk. In a TBA transaction, a seller agrees to deliver a security at a future date, but does not specify the particular security to be delivered. Instead, the seller agrees to accept any security that meets specified terms. TBA transactions involve the risk that the securities received may have less favorable characteristics than what was anticipated when the Fund entered into the transaction. TBA transactions are also subject to counterparty risk and will be exposed to changes in the value of the underlying investments during the term of the agreement.
F/m Yield Curve Steepening Strategy ETF | U S Treasury and Agency Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●U.S. Treasury and Agency Market Risk. The U.S. Treasury and agency market can be volatile, and the value of instruments correlated with these markets may fluctuate dramatically from day to day. U.S. Treasury and agency obligations may provide relatively lower returns than those of other securities. Similar to other debt instruments, U.S. Treasury and agency obligations are subject to debt instrument risk and interest rate risk. In addition, changes to the financial condition or credit rating of the U.S. Government may cause the value of U.S. Treasury and agency obligations to decline. U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. government and are generally considered to have negligible credit risk. Securities issued or guaranteed by federal agencies or authorities and U.S. government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. government.
F/m Yield Curve Steepening Strategy ETF | Valuation Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Valuation Risk. The prices provided by the Fund’s pricing services or independent dealers or the fair value determinations made by the valuation committee of the Adviser may be different from the prices used by other funds or from the prices at which securities are actually bought and sold. The prices of certain securities provided by pricing services may be subject to frequent and significant change, and will vary depending on the information that is available.
F/m Yield Curve Steepening Strategy ETF | F/m Yield Curve Steepening Strategy ETF Shares  
Prospectus [Line Items] rr_ProspectusLineItems  
Trading Symbol dei_TradingSymbol USTP
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.50%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets none
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.50%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 51
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 $ 160
F/m Yield Curve Flattening Strategy ETF  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk/Return [Heading] rr_RiskReturnHeading SUMMARY SECTION – F/m Yield Curve Flattening Strategy ETF (UFLT)
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock

The investment objective of the F/m Yield Curve Flattening Strategy ETF (the “F/m Yield Curve Flattening Fund” or the “Fund”) is to seek to implement a flattener yield curve strategy that is designed to benefit from the narrowing spread between short-term and long-term U.S. Treasury yields that typically occurs when shorter-maturity rates rise faster than longer-maturity rates, or when longer-maturity rates decline relative to shorter-maturity rates.
Expense [Heading] rr_ExpenseHeading Fees and Expenses
Expense Narrative [Text Block] rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the F/m Yield Curve Flattening Fund (“Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Operating Expenses Caption [Text] rr_OperatingExpensesCaption Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
Portfolio Turnover [Heading] rr_PortfolioTurnoverHeading Portfolio Turnover
Portfolio Turnover [Text Block] rr_PortfolioTurnoverTextBlock

The F/m Yield Curve Flattening 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. No portfolio turnover rate is provided for the Fund because the Fund had not commenced operations prior to the date of this Prospectus.
Expense Example [Heading] rr_ExpenseExampleHeading Example
Expense Example Narrative [Text Block] rr_ExpenseExampleNarrativeTextBlock

This Example is intended to help you compare the cost of investing in the F/m Yield Curve Flattening Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then hold or redeem all of your Shares at the end of those periods. The Example also assumes that: (1) your investment has a 5% return each year, and (2) the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading] rr_StrategyHeading Principal Investment Strategies
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock

The F/m Yield Curve Flattening Fund is an actively-managed exchange-traded fund (“ETF”) that seeks to implement a flattener yield curve strategy that is designed to benefit from the narrowing spread between short-term and long-term U.S. Treasury yields that typically occurs when shorter-maturity rates rise faster than longer-maturity rates, or when longer-maturity rates decline relative to shorter-maturity rates.

 

Under normal market conditions, F/m Investments LLC (the “Adviser”) seeks to achieve the Fund’s investment objective by investing at least 80% of the Fund’s net assets (plus any borrowings for investment purposes) in a combination of long and short positions in U.S. Treasury securities or derivatives, such as U.S. Treasury futures, interest rate swaps, and options, to express a view on the shape of the yield curve. Specifically, the Fund may:

 

●Take long positions in longer-duration U.S. Treasury securities or derivatives or affiliated ETFs to gain exposure to declining yields at the long end of the curve.

 

●Take short positions in shorter-duration U.S. Treasury securities or derivatives or affiliated ETFs to gain exposure to rising yields at the short end of the curve.

 

The Adviser actively manages the Fund’s positions based on market conditions, macroeconomic trends, and interest rate forecasts. The Fund’s portfolio is constructed and rebalanced periodically to maintain exposure aligned with the yield flattener objective, considering factors such as economic data, Federal Reserve policy, and global interest rate dynamics.

The Fund may also allocate a portion of its assets to cash, cash equivalents, or high-quality short-term instruments for liquidity and collateral purposes. The Fund does not seek to maintain a specific duration target, as its primary focus is on the relative movement between segments of the yield curve.

 

The Fund may enter into reverse repurchase agreements in amounts not exceeding one-third of the Fund’s total assets (including the amount borrowed). The Fund may invest in securities of other affiliated and unaffiliated ETFs registered under the Investment Company Act of 1940, as amended, that invest primarily in Fund eligible investments (collectively, “Underlying Funds”) to the extent permitted by applicable law and subject to certain restrictions.

 

The Fund may also seek to increase its income by lending securities. These loans will be secured by collateral (consisting of cash, U.S. government securities, or irrevocable letters of credit) maintained in an amount equal to at least 100% of the market value, determined daily, of the loaned securities. Cash collateral received by the Fund in connection with its lending of portfolio securities will be invested in short-term investments, including money market funds.

 

The F/m Yield Curve Flattening Fund has elected to qualify each year for treatment as a regulated investment company (“RIC”) under Subchapter M of Subtitle A, Chapter 1, of the Internal Revenue Code of 1986, as amended (the “Code”).
Risk [Heading] rr_RiskHeading Principal Investment Risks
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock

Performance Information: Performance information for the F/m Yield Curve Flattening Fund is not included because the Fund had not commenced operations prior to the date of this Prospectus. Performance information will be included once the Fund has at least one calendar year of performance. Updated performance information will be available on the Fund’s website at www.fminvest.com.
Performance One Year or Less [Text] rr_PerformanceOneYearOrLess Performance information will be included once the Fund has at least one calendar year of performance.
Performance Availability Website Address [Text] rr_PerformanceAvailabilityWebSiteAddress www.fminvest.com
F/m Yield Curve Flattening Strategy ETF | Risk Lose Money [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock As a result, you may lose money on your investment in the Fund, and there can be no assurance that the Fund will achieve its investment objective.
F/m Yield Curve Flattening Strategy ETF | Affiliated Fund Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Affiliated Fund Risk. Affiliated fund risk is the risk that the Adviser may select investments for the Fund based on its own financial interests or other business considerations rather than the Fund’s interests. The Adviser may be subject to potential conflicts of interest in selecting the Underlying Funds because the Underlying Funds pay an advisory fee to the Adviser based on their assets, the fees paid to the Adviser by some affiliated Underlying Funds may be higher than other Underlying Funds or the Underlying Funds may be in need of assets to enhance their appeal to other investors, liquidity and trading and/or to enable them to carry out their investment strategies. However, the Adviser is a fiduciary to the Fund and is legally obligated to act in the Fund’s best interest when selecting Underlying Funds.
F/m Yield Curve Flattening Strategy ETF | Asset Class Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Asset Class Risk. Securities and other assets in the Fund’s portfolio may underperform in comparison to the general financial markets, a particular financial market, or other asset classes.
F/m Yield Curve Flattening Strategy ETF | Concentration Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Concentration Risk. The Fund may be susceptible to an increased risk of loss, including losses due to adverse events that affect the Fund’s investments more than the market as a whole, to the extent that the Fund’s investments are concentrated in a particular issue, issuer or issuers, country, market segment, or asset class.
F/m Yield Curve Flattening Strategy ETF | Cyber Security Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Cyber Security Risk. Cyber security risk is the risk of an unauthorized breach and access to the Fund’s assets, Fund or customer data (including private shareholder information), or proprietary information, or the risk of an incident occurring that causes the Fund, the Adviser, custodian, transfer agent, distributor and other service providers and financial intermediaries to suffer data breaches, data corruption or lose operational functionality or prevent the Fund’s investors from purchasing, redeeming or exchanging shares or receiving distributions. While the Fund and the Adviser have established business continuity plans and risk management systems seeking to address system breaches or failures, there are inherent limitations in such plans and systems. Further, the Fund cannot control the cybersecurity plans and systems of the Fund’s service providers, market makers, or issuers of securities in which the Fund invests. The Fund and the Adviser have limited ability to prevent or mitigate cyber security incidents affecting third-party service providers, and such third-party service providers may have limited indemnification obligations to the Fund or the Adviser. Successful cyber-attacks or other cyber-failures or events affecting the Fund or its service providers may adversely impact and cause financial losses to the Fund or its shareholders. Issuers of securities in which the Fund invests are also subject to cyber security risks, and the value of these securities could decline if the issuers experience cyber-attacks or other cyber-failures.
F/m Yield Curve Flattening Strategy ETF | Duration Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Duration Risk. Duration is a measure of the price sensitivity of a debt security or portfolio to interest rate changes. Duration risk is the risk that longer-duration debt securities will be more volatile and thus more likely to decline in price, and to a greater extent, in a rising interest rate environment than shorter-duration debt securities.
F/m Yield Curve Flattening Strategy ETF | ETF Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●ETF Risk. The Fund is an ETF, and, as a result of an ETF’s structure, it is exposed to the following risks:

 

●Authorized Participants, Market Makers and Liquidity Providers Concentration Risk. Only an authorized participant (“AP”) may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of financial institutions that are institutional investors and may act as AP. In addition, there may be a limited number of market makers and/or liquidity providers in the marketplace. To the extent either of the following events occur, Note Fund Shares may trade at a material discount to net asset value (“NAV”) and possibly face delisting: (i) APs exit the business or otherwise become unable to process creation and/or redemption orders and no other APs step forward to perform these services, or (ii) market makers and/or liquidity providers exit the business or significantly reduce their business activities and no other entities step forward to perform their functions. These events, among others, may lead to the Fund Shares trading at a premium or discount to NAV. Thus, you may pay more (or less) than the NAV when you buy Shares of the Fund in the secondary market, and you may receive less (or more) than NAV when you sell those Shares in the secondary market. A diminished market for an ETF’s shares substantially increases the risk that a shareholder may pay considerably more or receive significantly less than the underlying value of the ETF shares bought or sold. In periods of market volatility, APs, market makers and/or liquidity providers may be less willing to transact in Fund Shares.

 

●Secondary Market Trading Risk. Although Shares are listed on a national securities exchange (the “Exchange”), and may be traded on U.S. exchanges other than the Exchange, there can be no assurance that an active or liquid trading market for them will develop or be maintained. In addition, trading in Shares on the Exchange may be halted. During periods of market stress, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount). This risk is heightened in times of market volatility or periods of steep market declines.

 

●Shares May Trade at Prices Other Than NAV Risk. As with all ETFs, Shares may be bought and sold in the secondary market at market prices. Shares trade on a stock exchange at prices at, above, or below the Fund’s most recent NAV. The Fund’s NAV is calculated at the end of each business day and fluctuates with changes in the market value of the Fund’s holdings. The trading price of the Shares fluctuates continuously throughout trading hours on the exchange, based on both the relative market supply of, and demand for, the Shares and the underlying value of the Fund’s portfolio holdings. As a result the trading prices of the Shares may deviate from the Fund’s NAV. Although it is expected that the market price of Shares will approximate the Fund’s NAV, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount). This risk is heightened in times of market volatility or periods of steep market declines. Any of these factors, among others, may lead to the Shares trading at a premium or discount to NAV.
F/m Yield Curve Flattening Strategy ETF | High Portfolio Turnover Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●High Portfolio Turnover Risk. The Fund may incur relatively high portfolio turnover. The active and frequent trading of the Fund’s portfolio securities may result in increased transaction costs to the Fund, including brokerage commissions, dealer mark-ups and other transaction costs, which could reduce the Fund’s return.
F/m Yield Curve Flattening Strategy ETF | Income Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Income Risk. The Fund’s income may decline if interest rates fall. This decline in income can occur because the Fund may subsequently invest in lower yielding bonds as bonds in its portfolio mature, are near maturity or are called, or the Fund otherwise needs to purchase additional bonds.
F/m Yield Curve Flattening Strategy ETF | Interest Rate Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Interest Rate Risk. Interest rate risk is the risk of losses attributable to changes in interest rates. In general, if prevailing interest rates rise, the values of debt instruments tend to fall, and if interest rates fall, the values of debt instruments tend to rise. Changes in the value of a debt instrument usually will not affect the amount of income the Fund receives from it but will generally affect the value of your investment in the Fund. Changes in interest rates may also affect the liquidity of the Fund’s investments in debt instruments. In general, the longer the maturity or duration of a debt instrument, the greater its sensitivity to changes in interest rates. The Fund is subject to the risk that the income generated by its investments may not keep pace with inflation. Actions by governments and central banking authorities can result in increases or decreases in interest rates, which may negatively affect the value of debt instruments held by the Fund and have a negative impact on the Fund’s performance and NAV. Rising interest rates may prompt redemptions from the Fund, which may force the Fund to sell investments at a time when it is not advantageous to do so, which could result in losses. During periods of very low or negative interest rates, the Fund may be unable to maintain positive returns or pay dividends to Fund shareholders. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, result in heightened market volatility and detract from the Fund’s performance to the extent the Fund is exposed to such interest rates. Additionally, under certain market conditions in which interest rates are low and the market prices for portfolio securities have increased, the Fund may have a very low or even negative yield. A low or negative yield would cause the Fund to lose money in certain conditions and over certain time periods. An increase in interest rates will generally cause the value of securities held by the Fund to decline, may lead to heightened volatility in the fixed-income markets and may adversely affect the liquidity of certain fixed-income investments, including those held by the Fund. The historically low-interest rate environment in recent years heightens the risks associated with rising interest rates.
F/m Yield Curve Flattening Strategy ETF | Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Market Risk. The trading prices of securities and other instruments fluctuate in response to a variety of factors. The Fund’s NAV and market price may fluctuate significantly in response to these and other factors including economic, political, financial, public health crises (such as epidemics or pandemics), war, acts of terrorism, recessions or other disruptive events (whether real, expected or perceived) in the local, regional or global markets. These factors could have a significant impact on the Fund and its investments and could result in increased premiums or discounts to the Fund’s NAV. As a result, an investor could lose money over short periods of time due to short-term market movements or long periods of time during prolonged market downturns.
F/m Yield Curve Flattening Strategy ETF | Market Trading Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Market Trading Risk. The Fund faces numerous market trading risks, including the potential lack of an active market for the Shares, losses from trading in secondary markets, and disruption in the creation/redemption process of the Fund. In stressed market conditions, the market for Shares may become less liquid in response to deteriorating liquidity in the markets for the Fund’s portfolio holdings, which may cause a variance in the market price of Shares and their underlying NAV. In addition, an exchange or market may issue trading halts on specific securities or financial instruments. As a result, the ability to trade certain securities or financial instruments may be restricted, which may disrupt the Fund’s creation/redemption process, potentially affect the price at which Shares trade in the secondary market, and/or result in the Fund being unable to trade certain securities or financial instruments at all. In these circumstances, the Fund may be unable to rebalance its portfolio, may be unable to accurately price its investments and/or may incur substantial trading losses. Any of these factors may lead to the Shares trading at a premium or discount to the Fund’s NAV.
F/m Yield Curve Flattening Strategy ETF | New Fund Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●New Fund Risk. The Fund is a newly organized management investment company with a limited operating history. In addition, there can be no assurance that the Fund will grow to, or maintain, an economically viable size, in which case the Board of Directors (the “Board”) of The RBB Fund, Inc. (the “Company”) may determine to liquidate the Fund.
F/m Yield Curve Flattening Strategy ETF | Operational Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Operational Risk. The Fund is exposed to operational risks arising from a number of factors, including, but not limited to, human error, processing and communication errors, errors of the Fund’s service providers, counterparties or other third parties, failed or inadequate processes and technology or systems failures. The Fund and the Adviser seek to reduce these operational risks through controls and procedures. However, these measures do not address every possible risk and may be inadequate to address these risks.
F/m Yield Curve Flattening Strategy ETF | Reinvestment Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Reinvestment Risk. Reinvestment risk is the risk that income from the Fund’s portfolio will decline if and when the Fund reinvests the proceeds from the disposition of its portfolio securities at market interest rates that are below the portfolio’s current earnings rate. A decline in income could negatively affect the market price of the Shares.
F/m Yield Curve Flattening Strategy ETF | Risk Of Investing In The United States [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Risk of Investing in the United States. Certain changes in the United States economy, such as when the economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.
F/m Yield Curve Flattening Strategy ETF | Securities Lending Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Securities Lending Risk. The Fund may engage in securities lending (i.e., lend portfolio securities to institutions, such as certain broker dealers). Securities lending involves the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. These events could also trigger adverse tax consequences for the Fund. The Fund could also experience a loss or delay in the recovery of its securities if the borrowing institution breaches its agreement with the Fund.
F/m Yield Curve Flattening Strategy ETF | US Treasury Obligations Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●U.S. Treasury Obligations Risk. While U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. Government, such securities are nonetheless subject to credit risk (i.e., the risk that the U.S. Government may be, or be perceived to be, unable or unwilling to honor its financial obligations, such as making payments). Securities issued or guaranteed by federal agencies or authorities and U.S. Government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. Government. U.S. Treasury obligations may differ from other securities in their interest rates, maturities, times of issuance and other characteristics and may provide relatively lower returns than those of other securities. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of the Fund’s U.S. Treasury obligations to decline.
F/m Yield Curve Flattening Strategy ETF | Active Management Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Active Management Risk. The Fund is actively managed using proprietary investment strategies and processes. There can be no guarantee that these strategies and processes will be successful or that the Fund will achieve its investment objective.
F/m Yield Curve Flattening Strategy ETF | Cash or Cash Equivalents Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Cash or Cash Equivalents Risk. At any time, the Fund may have significant investments in cash or cash equivalents. When a substantial portion of a portfolio is held in cash or cash equivalents, there is the risk that the value of the cash account, including interest, will not keep pace with inflation, thus reducing purchasing power over time. Additionally, in rising markets, holding cash or cash equivalents may adversely affect the Fund’s performance and the Fund may not achieve its investment objective.
F/m Yield Curve Flattening Strategy ETF | Counterparty Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Counterparty Risk. Counterparty risk is the risk that a counterparty to a swap contract or other similar investment instrument may default on its payment obligation to the Fund. Such a default may cause the value of an investment in the Fund to decrease.
F/m Yield Curve Flattening Strategy ETF | Derivatives Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Derivatives Risk. A Fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. These risks include (i) the risk that the counterparty to a derivative transaction may not fulfill its contractual obligations; (ii) risk of mispricing or improper valuation; and (iii) the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. Derivative prices are highly volatile and may fluctuate substantially during a short period of time. Such prices are influenced by numerous factors that affect the markets, including, but not limited to: changing supply and demand relationships; government programs and policies; national and international political and economic events, changes in interest rates, inflation and deflation and changes in supply and demand relationships. Trading derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities.
F/m Yield Curve Flattening Strategy ETF | Early Close Trading Halt Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Early Close/Trading Halt Risk. An exchange or market may close or issue trading halts on specific securities, or the ability to buy or sell certain securities or financial instruments may be restricted, which may prevent a Fund from buying or selling certain securities or financial instruments. In these circumstances, a Fund may be unable to rebalance its portfolio, may be unable to accurately price its investments and may incur substantial trading losses.
F/m Yield Curve Flattening Strategy ETF | Futures Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Futures Risk. Futures are standardized, exchange-traded contracts that obligate a purchaser to take delivery, and a seller to make delivery, of a specific amount of an asset at a specified future date at a specified price. The primary risks associated with the use of futures contracts and options are: (a) the imperfect correlation between the change in market value of the instruments held by the Fund and the price of the futures contract or option; (b) the possible lack of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; (c) losses caused by unanticipated market movements, which are potentially unlimited; (d) the investment adviser’s inability to predict correctly the direction of securities prices, interest rates, currency exchange rates and other economic factors; and (e) the possibility that the counterparty will default in the performance of its obligations.
F/m Yield Curve Flattening Strategy ETF | Illiquid Investments Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Illiquid Investments Risk. The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately.
F/m Yield Curve Flattening Strategy ETF | Issuer Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Issuer Risk. The performance of the Fund depends on the performance of individual securities or other assets to which the Fund has exposure. The value of securities or other assets may decline, or perform differently from the market as a whole, due to changes in the financial condition or credit rating of the issuer or counterparty.
F/m Yield Curve Flattening Strategy ETF | Leverage Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Leverage Risk. Using derivatives can create leverage, which can amplify the effects of market volatility on the Fund’s share price and make the Fund’s returns more volatile. The use of leverage may cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The use of leverage may also cause the Fund to have higher expenses than those of other funds that do not use such techniques.
F/m Yield Curve Flattening Strategy ETF | Liquidity Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Liquidity Risk. Certain securities held by the Fund may be difficult (or impossible) to sell at the time and at the price the Adviser would like. As a result, the Fund may have to hold these securities longer than it would like and may forego other investment opportunities. There is the possibility that the Fund may lose money or be prevented from realizing capital gains if it cannot sell a security at a particular time and price.
F/m Yield Curve Flattening Strategy ETF | Options Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Options Risk. When the Fund purchases a call option, it receives, in return for the premium it pays, the right to buy from the writer of the option the underlying security at a specified price at any time before the option expires. The Fund purchases call options in anticipation of an increase in the market value of securities that it intends ultimately to buy. During the life of the call option, a Fund is able to buy the underlying security at the exercise price regardless of any increase in the market price of the underlying security. In order for a call option to result in a gain, the market price of the underlying security must exceed the sum of the exercise price, the premium paid, and transaction costs.
F/m Yield Curve Flattening Strategy ETF | Over the Counter Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Over-the-Counter Market Risk. Securities and options traded in over-the-counter markets may trade less frequently and in limited volumes and thus exhibit more volatility and liquidity risk, and the prices paid by the Fund in over-the-counter transactions may include an undisclosed dealer markup. The Fund is also exposed to default by the over-the-counter option writer who may be unwilling or unable to perform its contractual obligations to the Fund.
F/m Yield Curve Flattening Strategy ETF | Pricing Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Pricing Risk. If market conditions make it difficult to value some investments, the Fund may value these investments using more subjective methods, such as fair value pricing. In such cases, the value determined for an investment could be different from the value realized upon such investment’s sale. As a result, you could pay more than the market value when buying Fund Shares or receive less than the market value when selling Fund Shares.
F/m Yield Curve Flattening Strategy ETF | Rate Linked Derivatives Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Rate-Linked Derivatives Risk. The Fund’s exposure to derivatives tied to interest rates subjects the Fund to greater volatility than investments in traditional securities, such as stocks and bonds. Investing in derivatives tied to interest rates, including through options tied to the shape of the U.S. interest rate curve, can be extremely volatile. The value of such investments may fluctuate rapidly based on a variety of factors, including overall market movements; economic events and policies; changes in interest rates or inflation rates; changes in monetary and exchange control programs; war; acts of terrorism; natural disasters; and technological developments. The Fund is expected to benefit from the options it holds if long-term U.S. interest rates rise during the time period in which the Fund holds the options. However, if long-term U.S. interest rates decrease, the Fund will lose money on the options, up to the amount invested in option premiums, and underperform an otherwise identical bond fund that had not used such options. Rate-linked derivatives may lose money if interest rates change in a manner not anticipated by the Adviser. An increase in interest rates may cause the value of securities held directly or indirectly by the Fund to decline to the extent that the Fund’s hedging strategy is not effectively implemented. Even if the Fund is hedged against losses due to long-term interest rate increases linked to U.S. interest rates, outright interest rate increases may also lead to heightened volatility in the fixed-income markets and may positively affect the value of the Fund’s options while negatively impacting the Fund’s investments in U.S. Treasuries. The Fund could lose money on the options held by the Fund, and the present value of the Fund’s portfolio investments could decrease if inflation increases. These interest rate-linked options may also cause the Fund’s net asset value and returns to be more volatile and expose the Fund to increased counterparty risk. Fluctuations in the U.S. interest rate curve or the price of the options owned by the Fund could materially adversely affect an investment in the Fund. The Fund’s investments in options are not intended to mitigate duration and credit risk or other factors influencing the price of U.S. government bonds, which may have a greater impact on the bonds’ returns than interest rate risk. Moreover, to the extent that interest rate risk has been priced into the government bonds owned directly or indirectly by the Fund, the Fund could underperform other investments even during periods of rising long-term U.S. interest rates. There is no guarantee that the Fund will have positive performance even in environments of sharply rising U.S. interest rates. There is no guarantee that the Fund will be able to successfully mitigate interest rate risk.
F/m Yield Curve Flattening Strategy ETF | Rating Agencies Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Rating Agencies Risk. Ratings are not an absolute standard of quality, but rather general indicators that reflect only the view of the originating rating agencies from which an explanation of the significance of such ratings may be obtained. There is no assurance that a particular rating will continue for any given period of time or that any such rating will not be revised downward or withdrawn entirely if, in the judgment of the agency establishing the rating, circumstances so warrant. A downward revision or withdrawal of such ratings, or either of them, may have an effect on the liquidity or market price of the securities in which the Fund invests.
F/m Yield Curve Flattening Strategy ETF | Reverse Repurchase Agreements Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Reverse Repurchase Agreements Risk. Reverse repurchase agreements are a form of secured borrowing and subject the Fund to the risks associated with leverage, including exposure to potential gains and losses in excess of the amount invested, resulting in an increase in the speculative character of the Fund’s outstanding shares. Reverse repurchase agreements involve the risk that the investment return earned by the Fund (from the investment of the proceeds) will be less than the interest expense of the transaction, that the market value of the securities sold by the Fund will decline below the price the Fund is obligated to pay to repurchase the securities, and that the other party may fail to return the securities in a timely manner or at all.
F/m Yield Curve Flattening Strategy ETF | Shorting US Treasury Securities Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Shorting U.S. Treasury Securities Risk. The Fund may seek short exposure to financial instruments such as U.S. Treasury securities. There is no guarantee that the returns on the Fund’s short positions will produce positive returns and the Fund could lose money if the short positions produce negative returns. U.S. Treasury prices are highly sensitive to changes in interest rates and a decrease in yields (increase in prices) could result in significant losses for short positions. Shorting typically requires borrowing securities, which involves reliance on the availability of lenders and custodians. The failure of a counterparty to deliver the securities may impact the Fund’s execution of its strategy.
F/m Yield Curve Flattening Strategy ETF | Swap Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Swap Risk. Swaps are subject to tracking risk because they may not be perfect substitutes for the instruments they are intended to hedge or replace. Over the counter swaps are subject to counterparty default. Leverage inherent in derivatives will tend to magnify the Fund’s losses.
F/m Yield Curve Flattening Strategy ETF | Swaptions Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Swaptions Risk. A “swaption” is a contract that gives a counterparty the right (but not the obligation) to enter into a new swap agreement or to shorten, extend, cancel or otherwise modify an existing swap agreement, at some designated future time on specified terms. The Fund may purchase interest rate payer swaptions. When the Fund purchases a swaption, it risks losing only the amount of the premium it has paid should it decide to let the option expire unexercised.
F/m Yield Curve Flattening Strategy ETF | TBA Securities Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●TBA Securities Risk. In a TBA transaction, a seller agrees to deliver a security at a future date, but does not specify the particular security to be delivered. Instead, the seller agrees to accept any security that meets specified terms. TBA transactions involve the risk that the securities received may have less favorable characteristics than what was anticipated when the Fund entered into the transaction. TBA transactions are also subject to counterparty risk and will be exposed to changes in the value of the underlying investments during the term of the agreement.
F/m Yield Curve Flattening Strategy ETF | U S Treasury and Agency Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●U.S. Treasury and Agency Market Risk. The U.S. Treasury and agency market can be volatile, and the value of instruments correlated with these markets may fluctuate dramatically from day to day. U.S. Treasury and agency obligations may provide relatively lower returns than those of other securities. Similar to other debt instruments, U.S. Treasury and agency obligations are subject to debt instrument risk and interest rate risk. In addition, changes to the financial condition or credit rating of the U.S. Government may cause the value of U.S. Treasury and agency obligations to decline. U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. government and are generally considered to have negligible credit risk. Securities issued or guaranteed by federal agencies or authorities and U.S. government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. government.
F/m Yield Curve Flattening Strategy ETF | Valuation Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Valuation Risk. The prices provided by the Fund’s pricing services or independent dealers or the fair value determinations made by the valuation committee of the Adviser may be different from the prices used by other funds or from the prices at which securities are actually bought and sold. The prices of certain securities provided by pricing services may be subject to frequent and significant change, and will vary depending on the information that is available.
F/m Yield Curve Flattening Strategy ETF | Fixed Income Securities Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Fixed-Income Market Risk. When the Fund invests in fixed income securities, the value of your investment in the Fund will fluctuate with changes in interest rates. Typically, a rise in interest rates causes a decline in the value of fixed income securities owned by the Fund. In general, the market price of fixed income securities with longer maturities or duration will increase or decrease more in response to changes in interest rates than shorter-term securities. Other risk factors include credit risk (the debtor may default), extension risk (an issuer may exercise its right to repay principal on a fixed rate obligation held by the Fund later than expected), and prepayment risk (the debtor may pay its obligation early, reducing the amount of interest payments). These risks could affect the value of a particular investment by the Fund, possibly causing the Fund’s share price and total return to be reduced and fluctuate more than other types of investments.
F/m Yield Curve Flattening Strategy ETF | F/m Yield Curve Flattening Strategy ETF Shares  
Prospectus [Line Items] rr_ProspectusLineItems  
Trading Symbol dei_TradingSymbol UFLT
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.50%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets none
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.50%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 51
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 $ 160
F/m Rising Interest Rates Strategy ETF  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk/Return [Heading] rr_RiskReturnHeading SUMMARY SECTION – F/m Rising Interest Rates Strategy ETF (URIZ)
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock

The investment objective of the F/m Rising Interest Rates Strategy ETF (the “F/m Rising Rates Fund” or the “Fund”) is to seek to implement a rising rate strategy that is designed to benefit from rising interest rates in both short-term and long-term U.S. Treasury yields.
Expense [Heading] rr_ExpenseHeading Fees and Expenses
Expense Narrative [Text Block] rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the F/m Rising Rates Fund (“Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Operating Expenses Caption [Text] rr_OperatingExpensesCaption Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
Portfolio Turnover [Heading] rr_PortfolioTurnoverHeading Portfolio Turnover
Portfolio Turnover [Text Block] rr_PortfolioTurnoverTextBlock

The F/m Rising Rates 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. No portfolio turnover rate is provided for the Fund because the Fund had not commenced operations prior to the date of this Prospectus.
Expense Example [Heading] rr_ExpenseExampleHeading Example
Expense Example Narrative [Text Block] rr_ExpenseExampleNarrativeTextBlock

This Example is intended to help you compare the cost of investing in the F/m Rising Rates Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then hold or redeem all of your Shares at the end of those periods. The Example also assumes that: (1) your investment has a 5% return each year, and (2) the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading] rr_StrategyHeading Principal Investment Strategies
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock

The F/m Rising Rates Fund is an actively-managed exchange-traded fund (“ETF”) that seeks to implement a rising rate strategy that is designed to benefit from rising interest rates in both short-term and long-term U.S. Treasury yields.

 

Under normal market conditions, F/m Investments LLC (the “Adviser”) seeks to achieve the Fund’s investment objective by investing at least 80% of the Fund’s net assets (plus any borrowings for investment purposes) in a combination of long and short positions in U.S. Treasury securities or derivatives, such as U.S. Treasury futures, interest rate swaps, and options, to express a view on the direction of interest rates. Specifically, the Fund may:

 

●Take short positions in longer-duration and shorter-duration U.S. Treasury securities or derivatives or affiliated ETFs to gain exposure to rising yields across the curve.

 

●Take long positions in U.S. Treasury securities or derivatives or affiliated ETFs to gain exposure to areas of the yield curve where yields may fall or rise less than other parts of the curve.

 

The Adviser actively manages the Fund’s positions based on market conditions, macroeconomic trends, and interest rate forecasts. The Fund’s portfolio is constructed and rebalanced periodically to maintain exposure aligned with rising rates strategy, considering factors such as economic data, Federal Reserve policy, and global interest rate dynamics.

 

The Fund may also allocate a portion of its assets to cash, cash equivalents, or high-quality short-term instruments for liquidity and collateral purposes. The Fund does not seek to maintain a specific duration target, as its primary focus is on the relative movement between segments of the yield curve. 

The Fund may enter into reverse repurchase agreements in amounts not exceeding one-third of the Fund’s total assets (including the amount borrowed). The Fund may invest in securities of other affiliated and unaffiliated ETFs registered under the Investment Company Act of 1940, as amended, that invest primarily in Fund eligible investments (collectively, “Underlying Funds”) to the extent permitted by applicable law and subject to certain restrictions.

 

The Fund may also seek to increase its income by lending securities. These loans will be secured by collateral (consisting of cash, U.S. government securities, or irrevocable letters of credit) maintained in an amount equal to at least 100% of the market value, determined daily, of the loaned securities. Cash collateral received by the Fund in connection with its lending of portfolio securities will be invested in short-term investments, including money market funds.

 

The F/m Rising Rates Fund has elected to qualify each year for treatment as a regulated investment company (“RIC”) under Subchapter M of Subtitle A, Chapter 1, of the Internal Revenue Code of 1986, as amended (the “Code”).
Risk [Heading] rr_RiskHeading Principal Investment Risks
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock

Performance Information: Performance information for the F/m Rising Rates Fund is not included because the Fund had not commenced operations prior to the date of this Prospectus. Performance information will be included once the Fund has at least one calendar year of performance. Updated performance information will be available on the Fund’s website at www.fminvest.com.
Performance One Year or Less [Text] rr_PerformanceOneYearOrLess Performance information will be included once the Fund has at least one calendar year of performance.
Performance Availability Website Address [Text] rr_PerformanceAvailabilityWebSiteAddress www.fminvest.com
F/m Rising Interest Rates Strategy ETF | Risk Lose Money [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock As a result, you may lose money on your investment in the Fund, and there can be no assurance that the Fund will achieve its investment objective.
F/m Rising Interest Rates Strategy ETF | Affiliated Fund Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Affiliated Fund Risk. Affiliated fund risk is the risk that the Adviser may select investments for the Fund based on its own financial interests or other business considerations rather than the Fund’s interests. The Adviser may be subject to potential conflicts of interest in selecting the Underlying Funds because the Underlying Funds pay an advisory fee to the Adviser based on their assets, the fees paid to the Adviser by some affiliated Underlying Funds may be higher than other Underlying Funds or the Underlying Funds may be in need of assets to enhance their appeal to other investors, liquidity and trading and/or to enable them to carry out their investment strategies. However, the Adviser is a fiduciary to the Fund and is legally obligated to act in the Fund’s best interest when selecting Underlying Funds.
F/m Rising Interest Rates Strategy ETF | Asset Class Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Asset Class Risk. Securities and other assets in the Fund’s portfolio may underperform in comparison to the general financial markets, a particular financial market, or other asset classes.
F/m Rising Interest Rates Strategy ETF | Concentration Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Concentration Risk. The Fund may be susceptible to an increased risk of loss, including losses due to adverse events that affect the Fund’s investments more than the market as a whole, to the extent that the Fund’s investments are concentrated in a particular issue, issuer or issuers, country, market segment, or asset class.
F/m Rising Interest Rates Strategy ETF | Cyber Security Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Cyber Security Risk. Cyber security risk is the risk of an unauthorized breach and access to the Fund’s assets, Fund or customer data (including private shareholder information), or proprietary information, or the risk of an incident occurring that causes the Fund, the Adviser, custodian, transfer agent, distributor and other service providers and financial intermediaries to suffer data breaches, data corruption or lose operational functionality or prevent the Fund’s investors from purchasing, redeeming or exchanging shares or receiving distributions. While the Fund and the Adviser have established business continuity plans and risk management systems seeking to address system breaches or failures, there are inherent limitations in such plans and systems. Further, the Fund cannot control the cybersecurity plans and systems of the Fund’s service providers, market makers, or issuers of securities in which the Fund invests. The Fund and the Adviser have limited ability to prevent or mitigate cyber security incidents affecting third-party service providers, and such third-party service providers may have limited indemnification obligations to the Fund or the Adviser. Successful cyber-attacks or other cyber-failures or events affecting the Fund or its service providers may adversely impact and cause financial losses to the Fund or its shareholders. Issuers of securities in which the Fund invests are also subject to cyber security risks, and the value of these securities could decline if the issuers experience cyber-attacks or other cyber-failures.
F/m Rising Interest Rates Strategy ETF | Duration Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Duration Risk. Duration is a measure of the price sensitivity of a debt security or portfolio to interest rate changes. Duration risk is the risk that longer-duration debt securities will be more volatile and thus more likely to decline in price, and to a greater extent, in a rising interest rate environment than shorter-duration debt securities.
F/m Rising Interest Rates Strategy ETF | ETF Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●ETF Risk. The Fund is an ETF, and, as a result of an ETF’s structure, it is exposed to the following risks:

 

●Authorized Participants, Market Makers and Liquidity Providers Concentration Risk. Only an authorized participant (“AP”) may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of financial institutions that are institutional investors and may act as AP. In addition, there may be a limited number of market makers and/or liquidity providers in the marketplace. To the extent either of the following events occur, Note Fund Shares may trade at a material discount to net asset value (“NAV”) and possibly face delisting: (i) APs exit the business or otherwise become unable to process creation and/or redemption orders and no other APs step forward to perform these services, or (ii) market makers and/or liquidity providers exit the business or significantly reduce their business activities and no other entities step forward to perform their functions. These events, among others, may lead to the Fund Shares trading at a premium or discount to NAV. Thus, you may pay more (or less) than the NAV when you buy Shares of the Fund in the secondary market, and you may receive less (or more) than NAV when you sell those Shares in the secondary market. A diminished market for an ETF’s shares substantially increases the risk that a shareholder may pay considerably more or receive significantly less than the underlying value of the ETF shares bought or sold. In periods of market volatility, APs, market makers and/or liquidity providers may be less willing to transact in Fund Shares.

 

●Secondary Market Trading Risk. Although Shares are listed on a national securities exchange (the “Exchange”), and may be traded on U.S. exchanges other than the Exchange, there can be no assurance that an active or liquid trading market for them will develop or be maintained. In addition, trading in Shares on the Exchange may be halted. During periods of market stress, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount). This risk is heightened in times of market volatility or periods of steep market declines.

 

●Shares May Trade at Prices Other Than NAV Risk. As with all ETFs, Shares may be bought and sold in the secondary market at market prices. Shares trade on a stock exchange at prices at, above, or below the Fund’s most recent NAV. The Fund’s NAV is calculated at the end of each business day and fluctuates with changes in the market value of the Fund’s holdings. The trading price of the Shares fluctuates continuously throughout trading hours on the exchange, based on both the relative market supply of, and demand for, the Shares and the underlying value of the Fund’s portfolio holdings. As a result the trading prices of the Shares may deviate from the Fund’s NAV. Although it is expected that the market price of Shares will approximate the Fund’s NAV, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount). This risk is heightened in times of market volatility or periods of steep market declines. Any of these factors, among others, may lead to the Shares trading at a premium or discount to NAV.
F/m Rising Interest Rates Strategy ETF | Fixed Income Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Fixed-Income Market Risk. When the Fund invests in fixed income securities, the value of your investment in the Fund will fluctuate with changes in interest rates. Typically, a rise in interest rates causes a decline in the value of fixed income securities owned by the Fund. In general, the market price of fixed income securities with longer maturities or duration will increase or decrease more in response to changes in interest rates than shorter-term securities. Other risk factors include credit risk (the debtor may default), extension risk (an issuer may exercise its right to repay principal on a fixed rate obligation held by the Fund later than expected), and prepayment risk (the debtor may pay its obligation early, reducing the amount of interest payments). These risks could affect the value of a particular investment by the Fund, possibly causing the Fund’s share price and total return to be reduced and fluctuate more than other types of investments.
F/m Rising Interest Rates Strategy ETF | High Portfolio Turnover Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●High Portfolio Turnover Risk. The Fund may incur relatively high portfolio turnover. The active and frequent trading of the Fund’s portfolio securities may result in increased transaction costs to the Fund, including brokerage commissions, dealer mark-ups and other transaction costs, which could reduce the Fund’s return.
F/m Rising Interest Rates Strategy ETF | Income Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Income Risk. The Fund’s income may decline if interest rates fall. This decline in income can occur because the Fund may subsequently invest in lower yielding bonds as bonds in its portfolio mature, are near maturity or are called, or the Fund otherwise needs to purchase additional bonds.
F/m Rising Interest Rates Strategy ETF | Interest Rate Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Interest Rate Risk. Interest rate risk is the risk of losses attributable to changes in interest rates. In general, if prevailing interest rates rise, the values of debt instruments tend to fall, and if interest rates fall, the values of debt instruments tend to rise. Changes in the value of a debt instrument usually will not affect the amount of income the Fund receives from it but will generally affect the value of your investment in the Fund. Changes in interest rates may also affect the liquidity of the Fund’s investments in debt instruments. In general, the longer the maturity or duration of a debt instrument, the greater its sensitivity to changes in interest rates. The Fund is subject to the risk that the income generated by its investments may not keep pace with inflation. Actions by governments and central banking authorities can result in increases or decreases in interest rates, which may negatively affect the value of debt instruments held by the Fund and have a negative impact on the Fund’s performance and NAV. Rising interest rates may prompt redemptions from the Fund, which may force the Fund to sell investments at a time when it is not advantageous to do so, which could result in losses. During periods of very low or negative interest rates, the Fund may be unable to maintain positive returns or pay dividends to Fund shareholders. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, result in heightened market volatility and detract from the Fund’s performance to the extent the Fund is exposed to such interest rates. Additionally, under certain market conditions in which interest rates are low and the market prices for portfolio securities have increased, the Fund may have a very low or even negative yield. A low or negative yield would cause the Fund to lose money in certain conditions and over certain time periods. An increase in interest rates will generally cause the value of securities held by the Fund to decline, may lead to heightened volatility in the fixed-income markets and may adversely affect the liquidity of certain fixed-income investments, including those held by the Fund. The historically low-interest rate environment in recent years heightens the risks associated with rising interest rates.
F/m Rising Interest Rates Strategy ETF | Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Market Risk. The trading prices of securities and other instruments fluctuate in response to a variety of factors. The Fund’s NAV and market price may fluctuate significantly in response to these and other factors including economic, political, financial, public health crises (such as epidemics or pandemics) or other disruptive events (whether real, expected or perceived) in the U.S. and global markets. As a result, an investor could lose money over short or long periods of time.
F/m Rising Interest Rates Strategy ETF | Market Trading Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Market Trading Risk. The Fund faces numerous market trading risks, including the potential lack of an active market for the Shares, losses from trading in secondary markets, and disruption in the creation/redemption process of the Fund. In stressed market conditions, the market for Shares may become less liquid in response to deteriorating liquidity in the markets for the Fund’s portfolio holdings, which may cause a variance in the market price of Shares and their underlying NAV. In addition, an exchange or market may issue trading halts on specific securities or financial instruments. As a result, the ability to trade certain securities or financial instruments may be restricted, which may disrupt the Fund’s creation/redemption process, potentially affect the price at which Shares trade in the secondary market, and/or result in the Fund being unable to trade certain securities or financial instruments at all. In these circumstances, the Fund may be unable to rebalance its portfolio, may be unable to accurately price its investments and/or may incur substantial trading losses. Any of these factors may lead to the Shares trading at a premium or discount to the Fund’s NAV.
F/m Rising Interest Rates Strategy ETF | New Fund Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●New Fund Risk. The Fund is a newly organized management investment company with a limited operating history. In addition, there can be no assurance that the Fund will grow to, or maintain, an economically viable size, in which case the Board of Directors (the “Board”) of The RBB Fund, Inc. (the “Company”) may determine to liquidate the Fund.
F/m Rising Interest Rates Strategy ETF | Operational Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Operational Risk. The Fund is exposed to operational risks arising from a number of factors, including, but not limited to, human error, processing and communication errors, errors of the Fund’s service providers, counterparties or other third parties, failed or inadequate processes and technology or systems failures. The Fund and the Adviser seek to reduce these operational risks through controls and procedures. However, these measures do not address every possible risk and may be inadequate to address these risks.
F/m Rising Interest Rates Strategy ETF | Reinvestment Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Reinvestment Risk. Reinvestment risk is the risk that income from the Fund’s portfolio will decline if and when the Fund reinvests the proceeds from the disposition of its portfolio securities at market interest rates that are below the portfolio’s current earnings rate. A decline in income could negatively affect the market price of the Shares.
F/m Rising Interest Rates Strategy ETF | Risk Of Investing In The United States [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Risk of Investing in the United States. Certain changes in the United States economy, such as when the economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.
F/m Rising Interest Rates Strategy ETF | Securities Lending Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Securities Lending Risk. The Fund may engage in securities lending (i.e., lend portfolio securities to institutions, such as certain broker dealers). Securities lending involves the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. These events could also trigger adverse tax consequences for the Fund. The Fund could also experience a loss or delay in the recovery of its securities if the borrowing institution breaches its agreement with the Fund.
F/m Rising Interest Rates Strategy ETF | US Treasury Obligations Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●U.S. Treasury Obligations Risk. While U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. Government, such securities are nonetheless subject to credit risk (i.e., the risk that the U.S. Government may be, or be perceived to be, unable or unwilling to honor its financial obligations, such as making payments). Securities issued or guaranteed by federal agencies or authorities and U.S. Government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. Government. U.S. Treasury obligations may differ from other securities in their interest rates, maturities, times of issuance and other characteristics and may provide relatively lower returns than those of other securities. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of the Fund’s U.S. Treasury obligations to decline.
F/m Rising Interest Rates Strategy ETF | Active Management Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Active Management Risk. The Fund is actively managed using proprietary investment strategies and processes. There can be no guarantee that these strategies and processes will be successful or that the Fund will achieve its investment objective.
F/m Rising Interest Rates Strategy ETF | Cash or Cash Equivalents Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Cash or Cash Equivalents Risk. At any time, the Fund may have significant investments in cash or cash equivalents. When a substantial portion of a portfolio is held in cash or cash equivalents, there is the risk that the value of the cash account, including interest, will not keep pace with inflation, thus reducing purchasing power over time. Additionally, in rising markets, holding cash or cash equivalents may adversely affect the Fund’s performance and the Fund may not achieve its investment objective.
F/m Rising Interest Rates Strategy ETF | Counterparty Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Counterparty Risk. Counterparty risk is the risk that a counterparty to a swap contract or other similar investment instrument may default on its payment obligation to the Fund. Such a default may cause the value of an investment in the Fund to decrease.
F/m Rising Interest Rates Strategy ETF | Derivatives Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Derivatives Risk. A Fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. These risks include (i) the risk that the counterparty to a derivative transaction may not fulfill its contractual obligations; (ii) risk of mispricing or improper valuation; and (iii) the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. Derivative prices are highly volatile and may fluctuate substantially during a short period of time. Such prices are influenced by numerous factors that affect the markets, including, but not limited to: changing supply and demand relationships; government programs and policies; national and international political and economic events, changes in interest rates, inflation and deflation and changes in supply and demand relationships. Trading derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities.
F/m Rising Interest Rates Strategy ETF | Early Close Trading Halt Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Early Close/Trading Halt Risk. An exchange or market may close or issue trading halts on specific securities, or the ability to buy or sell certain securities or financial instruments may be restricted, which may prevent a Fund from buying or selling certain securities or financial instruments. In these circumstances, a Fund may be unable to rebalance its portfolio, may be unable to accurately price its investments and may incur substantial trading losses.
F/m Rising Interest Rates Strategy ETF | Futures Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Futures Risk. Futures are standardized, exchange-traded contracts that obligate a purchaser to take delivery, and a seller to make delivery, of a specific amount of an asset at a specified future date at a specified price. The primary risks associated with the use of futures contracts and options are: (a) the imperfect correlation between the change in market value of the instruments held by the Fund and the price of the futures contract or option; (b) the possible lack of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; (c) losses caused by unanticipated market movements, which are potentially unlimited; (d) the investment adviser’s inability to predict correctly the direction of securities prices, interest rates, currency exchange rates and other economic factors; and (e) the possibility that the counterparty will default in the performance of its obligations.
F/m Rising Interest Rates Strategy ETF | Illiquid Investments Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Illiquid Investments Risk. The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately.
F/m Rising Interest Rates Strategy ETF | Issuer Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Issuer Risk. The performance of the Fund depends on the performance of individual securities or other assets to which the Fund has exposure. The value of securities or other assets may decline, or perform differently from the market as a whole, due to changes in the financial condition or credit rating of the issuer or counterparty.
F/m Rising Interest Rates Strategy ETF | Leverage Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Leverage Risk. Using derivatives can create leverage, which can amplify the effects of market volatility on the Fund's share price and make the Fund's returns more volatile. The use of leverage may cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The use of leverage may also cause the Fund to have higher expenses than those of other funds that do not use such techniques.
F/m Rising Interest Rates Strategy ETF | Liquidity Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Liquidity Risk. Certain securities held by the Fund may be difficult (or impossible) to sell at the time and at the price the Adviser would like. As a result, the Fund may have to hold these securities longer than it would like and may forego other investment opportunities. There is the possibility that the Fund may lose money or be prevented from realizing capital gains if it cannot sell a security at a particular time and price.
F/m Rising Interest Rates Strategy ETF | Options Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Options Risk. When the Fund purchases a call option, it receives, in return for the premium it pays, the right to buy from the writer of the option the underlying security at a specified price at any time before the option expires. The Fund purchases call options in anticipation of an increase in the market value of securities that it intends ultimately to buy. During the life of the call option, a Fund is able to buy the underlying security at the exercise price regardless of any increase in the market price of the underlying security. In order for a call option to result in a gain, the market price of the underlying security must exceed the sum of the exercise price, the premium paid, and transaction costs.
F/m Rising Interest Rates Strategy ETF | Over the Counter Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Over-the-Counter Market Risk. Securities and options traded in over-the-counter markets may trade less frequently and in limited volumes and thus exhibit more volatility and liquidity risk, and the prices paid by the Fund in over-the-counter transactions may include an undisclosed dealer markup. The Fund is also exposed to default by the over-the-counter option writer who may be unwilling or unable to perform its contractual obligations to the Fund.
F/m Rising Interest Rates Strategy ETF | Pricing Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Pricing Risk. If market conditions make it difficult to value some investments, the Fund may value these investments using more subjective methods, such as fair value pricing. In such cases, the value determined for an investment could be different from the value realized upon such investment’s sale. As a result, you could pay more than the market value when buying Fund Shares or receive less than the market value when selling Fund Shares.
F/m Rising Interest Rates Strategy ETF | Rate Linked Derivatives Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Rate-Linked Derivatives Risk. The Fund’s exposure to derivatives tied to interest rates subjects the Fund to greater volatility than investments in traditional securities, such as stocks and bonds. Investing in derivatives tied to interest rates, including through options tied to the shape of the U.S. interest rate curve, can be extremely volatile. The value of such investments may fluctuate rapidly based on a variety of factors, including overall market movements; economic events and policies; changes in interest rates or inflation rates; changes in monetary and exchange control programs; war; acts of terrorism; natural disasters; and technological developments. The Fund is expected to benefit from the options it holds if long-term U.S. interest rates rise during the time period in which the Fund holds the options. However, if long-term U.S. interest rates decrease, the Fund will lose money on the options, up to the amount invested in option premiums, and underperform an otherwise identical bond fund that had not used such options. Rate-linked derivatives may lose money if interest rates change in a manner not anticipated by the Adviser. An increase in interest rates may cause the value of securities held directly or indirectly by the Fund to decline to the extent that the Fund’s hedging strategy is not effectively implemented. Even if the Fund is hedged against losses due to long-term interest rate increases linked to U.S. interest rates, outright interest rate increases may also lead to heightened volatility in the fixed-income markets and may positively affect the value of the Fund’s options while negatively impacting the Fund’s investments in U.S. Treasuries. The Fund could lose money on the options held by the Fund, and the present value of the Fund’s portfolio investments could decrease if inflation increases. These interest rate-linked options may also cause the Fund’s net asset value and returns to be more volatile and expose the Fund to increased counterparty risk. Fluctuations in the U.S. interest rate curve or the price of the options owned by the Fund could materially adversely affect an investment in the Fund. The Fund’s investments in options are not intended to mitigate duration and credit risk or other factors influencing the price of U.S. government bonds, which may have a greater impact on the bonds’ returns than interest rate risk. Moreover, to the extent that interest rate risk has been priced into the government bonds owned directly or indirectly by the Fund, the Fund could underperform other investments even during periods of rising long-term U.S. interest rates. There is no guarantee that the Fund will have positive performance even in environments of sharply rising U.S. interest rates. There is no guarantee that the Fund will be able to successfully mitigate interest rate risk.
F/m Rising Interest Rates Strategy ETF | Rating Agencies Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Rating Agencies Risk. Ratings are not an absolute standard of quality, but rather general indicators that reflect only the view of the originating rating agencies from which an explanation of the significance of such ratings may be obtained. There is no assurance that a particular rating will continue for any given period of time or that any such rating will not be revised downward or withdrawn entirely if, in the judgment of the agency establishing the rating, circumstances so warrant. A downward revision or withdrawal of such ratings, or either of them, may have an effect on the liquidity or market price of the securities in which the Fund invests.
F/m Rising Interest Rates Strategy ETF | Reverse Repurchase Agreements Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Reverse Repurchase Agreements Risk. Reverse repurchase agreements are a form of secured borrowing and subject the Fund to the risks associated with leverage, including exposure to potential gains and losses in excess of the amount invested, resulting in an increase in the speculative character of the Fund’s outstanding shares. Reverse repurchase agreements involve the risk that the investment return earned by the Fund (from the investment of the proceeds) will be less than the interest expense of the transaction, that the market value of the securities sold by the Fund will decline below the price the Fund is obligated to pay to repurchase the securities, and that the other party may fail to return the securities in a timely manner or at all.
F/m Rising Interest Rates Strategy ETF | Shorting US Treasury Securities Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Shorting U.S. Treasury Securities Risk. The Fund may seek short exposure to financial instruments such as U.S. Treasury securities. There is no guarantee that the returns on the Fund’s short positions will produce positive returns and the Fund could lose money if the short positions produce negative returns. U.S. Treasury prices are highly sensitive to changes in interest rates and a decrease in yields (increase in prices) could result in significant losses for short positions. Shorting typically requires borrowing securities, which involves reliance on the availability of lenders and custodians. The failure of a counterparty to deliver the securities may impact the Fund’s execution of its strategy.
F/m Rising Interest Rates Strategy ETF | Swap Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Swap Risk. Swaps are subject to tracking risk because they may not be perfect substitutes for the instruments they are intended to hedge or replace. Over the counter swaps are subject to counterparty default. Leverage inherent in derivatives will tend to magnify the Fund’s losses.
F/m Rising Interest Rates Strategy ETF | Swaptions Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Swaptions Risk. A “swaption” is a contract that gives a counterparty the right (but not the obligation) to enter into a new swap agreement or to shorten, extend, cancel or otherwise modify an existing swap agreement, at some designated future time on specified terms. The Fund may purchase interest rate payer swaptions. When the Fund purchases a swaption, it risks losing only the amount of the premium it has paid should it decide to let the option expire unexercised.
F/m Rising Interest Rates Strategy ETF | TBA Securities Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●TBA Securities Risk. In a TBA transaction, a seller agrees to deliver a security at a future date, but does not specify the particular security to be delivered. Instead, the seller agrees to accept any security that meets specified terms. TBA transactions involve the risk that the securities received may have less favorable characteristics than what was anticipated when the Fund entered into the transaction. TBA transactions are also subject to counterparty risk and will be exposed to changes in the value of the underlying investments during the term of the agreement.
F/m Rising Interest Rates Strategy ETF | U S Treasury and Agency Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●U.S. Treasury and Agency Market Risk. The U.S. Treasury and agency market can be volatile, and the value of instruments correlated with these markets may fluctuate dramatically from day to day. U.S. Treasury and agency obligations may provide relatively lower returns than those of other securities. Similar to other debt instruments, U.S. Treasury and agency obligations are subject to debt instrument risk and interest rate risk. In addition, changes to the financial condition or credit rating of the U.S. Government may cause the value of U.S. Treasury and agency obligations to decline. U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. government and are generally considered to have negligible credit risk. Securities issued or guaranteed by federal agencies or authorities and U.S. government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. government.
F/m Rising Interest Rates Strategy ETF | Valuation Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Valuation Risk. The prices provided by the Fund’s pricing services or independent dealers or the fair value determinations made by the valuation committee of the Adviser may be different from the prices used by other funds or from the prices at which securities are actually bought and sold. The prices of certain securities provided by pricing services may be subject to frequent and significant change, and will vary depending on the information that is available.
F/m Rising Interest Rates Strategy ETF | F/m Rising Interest Rates Strategy ETF Shares  
Prospectus [Line Items] rr_ProspectusLineItems  
Trading Symbol dei_TradingSymbol URIZ
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.50%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets none
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.50%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 51
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 $ 160
F/m Falling Interest Rates Strategy ETF  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk/Return [Heading] rr_RiskReturnHeading SUMMARY SECTION – F/m Falling Interest Rates Strategy ETF (UFAL)
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock

The investment objective of the F/m Falling Interest Rates Strategy ETF (the “F/m Falling Rates Fund” or the “Fund”) is to seek to implement a falling rate strategy that is designed to benefit from falling interest rates in both short-term and long-term U.S. Treasury yields.
Expense [Heading] rr_ExpenseHeading Fees and Expenses
Expense Narrative [Text Block] rr_ExpenseNarrativeTextBlock

This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the F/m Falling Rates Fund (“Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.
Operating Expenses Caption [Text] rr_OperatingExpensesCaption Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
Portfolio Turnover [Heading] rr_PortfolioTurnoverHeading Portfolio Turnover
Portfolio Turnover [Text Block] rr_PortfolioTurnoverTextBlock

The F/m Falling Rates 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. No portfolio turnover rate is provided for the Fund because the Fund had not commenced operations prior to the date of this Prospectus.
Expense Example [Heading] rr_ExpenseExampleHeading Example
Expense Example Narrative [Text Block] rr_ExpenseExampleNarrativeTextBlock

This Example is intended to help you compare the cost of investing in the F/m Falling Rates Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then hold or redeem all of your Shares at the end of those periods. The Example also assumes that: (1) your investment has a 5% return each year, and (2) the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading] rr_StrategyHeading Principal Investment Strategies
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock

The F/m Falling Rates Fund is an actively-managed exchange-traded fund (“ETF”) that seeks to implement a falling rate strategy that is designed to benefit from falling interest rates in both short-term and long-term U.S. Treasury yields.

 

Under normal market conditions, F/m Investments LLC (the “Adviser”) seeks to achieve the Fund’s investment objective by investing at least 80% of the Fund’s net assets (plus any borrowings for investment purposes) in a combination of long and short positions in U.S. Treasury securities or derivatives, such as U.S. Treasury futures, interest rate swaps, and options, to express a view on the direction of interest rates. Specifically, the Fund may:

 

●Take long positions in longer-duration and shorter-duration U.S. Treasury securities or derivatives or affiliated ETFs to gain exposure to falling yields across the curve.

 

●Take short positions in U.S. Treasury securities or derivatives or affiliated ETFs to gain exposure to areas of the yield curve where yields may rise or fall less than other parts of the curve.

 

The Adviser actively manages the Fund’s positions based on market conditions, macroeconomic trends, and interest rate forecasts. The Fund’s portfolio is constructed and rebalanced periodically to maintain exposure aligned with the rising rates view, considering factors such as economic data, Federal Reserve policy, and global interest rate dynamics.

 

The Fund may also allocate a portion of its assets to cash, cash equivalents, or high-quality short-term instruments for liquidity and collateral purposes. The Fund does not seek to maintain a specific duration target, as its primary focus is on the relative movement between segments of the yield curve.

The Fund may enter into reverse repurchase agreements in amounts not exceeding one-third of the Fund’s total assets (including the amount borrowed). The Fund may invest in securities of other affiliated and unaffiliated ETFs registered under the Investment Company Act of 1940, as amended, that invest primarily in Fund eligible investments (collectively, “Underlying Funds”) to the extent permitted by applicable law and subject to certain restrictions.

 

The Fund may also seek to increase its income by lending securities. These loans will be secured by collateral (consisting of cash, U.S. government securities, or irrevocable letters of credit) maintained in an amount equal to at least 100% of the market value, determined daily, of the loaned securities. Cash collateral received by the Fund in connection with its lending of portfolio securities will be invested in short-term investments, including money market funds.

 

The F/m Falling Rates Fund has elected to qualify each year for treatment as a regulated investment company (“RIC”) under Subchapter M of Subtitle A, Chapter 1, of the Internal Revenue Code of 1986, as amended (the “Code”).
Risk [Heading] rr_RiskHeading Principal Investment Risks
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock

Performance Information: Performance information for the F/m Falling Rates Fund is not included because the Fund had not commenced operations prior to the date of this Prospectus. Performance information will be included once the Fund has at least one calendar year of performance. Updated performance information will be available on the Fund’s website at www.fminvest.com.
Performance One Year or Less [Text] rr_PerformanceOneYearOrLess Performance information will be included once the Fund has at least one calendar year of performance.
Performance Availability Website Address [Text] rr_PerformanceAvailabilityWebSiteAddress www.fminvest.com
F/m Falling Interest Rates Strategy ETF | Risk Lose Money [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock As a result, you may lose money on your investment in the Fund, and there can be no assurance that the Fund will achieve its investment objective.
F/m Falling Interest Rates Strategy ETF | Affiliated Fund Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Affiliated Fund Risk. Affiliated fund risk is the risk that the Adviser may select investments for the Fund based on its own financial interests or other business considerations rather than the Fund’s interests. The Adviser may be subject to potential conflicts of interest in selecting the Underlying Funds because the Underlying Funds pay an advisory fee to the Adviser based on their assets, the fees paid to the Adviser by some affiliated Underlying Funds may be higher than other Underlying Funds or the Underlying Funds may be in need of assets to enhance their appeal to other investors, liquidity and trading and/or to enable them to carry out their investment strategies. However, the Adviser is a fiduciary to the Fund and is legally obligated to act in the Fund’s best interest when selecting Underlying Funds.
F/m Falling Interest Rates Strategy ETF | Asset Class Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Asset Class Risk. The securities and other assets in the Fund’s portfolio may underperform in comparison to financial markets generally, a particular financial market, or other asset classes.
F/m Falling Interest Rates Strategy ETF | Concentration Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Concentration Risk. The Fund may be susceptible to an increased risk of loss, including losses due to adverse events that affect the Fund’s investments more than the market as a whole, to the extent that the Fund’s investments are concentrated in a particular issue, issuer or issuers, country, market segment, or asset class.
F/m Falling Interest Rates Strategy ETF | Cyber Security Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Cyber Security Risk. Cyber security risk is the risk of an unauthorized breach and access to the Fund’s assets, Fund or customer data (including private shareholder information), or proprietary information, or the risk of an incident occurring that causes the Fund, the Adviser, custodian, transfer agent, distributor and other service providers and financial intermediaries to suffer data breaches, data corruption or lose operational functionality or prevent the Fund’s investors from purchasing, redeeming or exchanging shares or receiving distributions. While the Fund and the Adviser have established business continuity plans and risk management systems seeking to address system breaches or failures, there are inherent limitations in such plans and systems. Further, the Fund cannot control the cybersecurity plans and systems of the Fund’s service providers, market makers, or issuers of securities in which the Fund invests. The Fund and the Adviser have limited ability to prevent or mitigate cyber security incidents affecting third-party service providers, and such third-party service providers may have limited indemnification obligations to the Fund or the Adviser. Successful cyber-attacks or other cyber-failures or events affecting the Fund or its service providers may adversely impact and cause financial losses to the Fund or its shareholders. Issuers of securities in which the Fund invests are also subject to cyber security risks, and the value of these securities could decline if the issuers experience cyber-attacks or other cyber-failures.
F/m Falling Interest Rates Strategy ETF | Duration Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Duration Risk. Duration is a measure of the price sensitivity of a debt security or portfolio to interest rate changes. Duration risk is the risk that longer-duration debt securities will be more volatile and thus more likely to decline in price, and to a greater extent, in a rising interest rate environment than shorter-duration debt securities.
F/m Falling Interest Rates Strategy ETF | ETF Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●ETF Risk. The Fund is an ETF, and, as a result of an ETF’s structure, it is exposed to the following risks:

 

●Authorized Participants, Market Makers and Liquidity Providers Concentration Risk. Only an authorized participant (“AP”) may engage in creation or redemption transactions directly with the Fund. The Fund has a limited number of financial institutions that are institutional investors and may act as AP. In addition, there may be a limited number of market makers and/or liquidity providers in the marketplace. To the extent either of the following events occur, Note Fund Shares may trade at a material discount to net asset value (“NAV”) and possibly face delisting: (i) APs exit the business or otherwise become unable to process creation and/or redemption orders and no other APs step forward to perform these services, or (ii) market makers and/or liquidity providers exit the business or significantly reduce their business activities and no other entities step forward to perform their functions. These events, among others, may lead to the Fund Shares trading at a premium or discount to NAV. Thus, you may pay more (or less) than the NAV when you buy Shares of the Fund in the secondary market, and you may receive less (or more) than NAV when you sell those Shares in the secondary market. A diminished market for an ETF’s shares substantially increases the risk that a shareholder may pay considerably more or receive significantly less than the underlying value of the ETF shares bought or sold. In periods of market volatility, APs, market makers and/or liquidity providers may be less willing to transact in Fund Shares.

 

●Secondary Market Trading Risk. Although Shares are listed on a national securities exchange (the “Exchange”), and may be traded on U.S. exchanges other than the Exchange, there can be no assurance that an active or liquid trading market for them will develop or be maintained. In addition, trading in Shares on the Exchange may be halted. During periods of market stress, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount). This risk is heightened in times of market volatility or periods of steep market declines.

 

●Shares May Trade at Prices Other Than NAV Risk. As with all ETFs, Shares may be bought and sold in the secondary market at market prices. Shares trade on a stock exchange at prices at, above, or below the Fund’s most recent NAV. The Fund’s NAV is calculated at the end of each business day and fluctuates with changes in the market value of the Fund’s holdings. The trading price of the Shares fluctuates continuously throughout trading hours on the exchange, based on both the relative market supply of, and demand for, the Shares and the underlying value of the Fund’s portfolio holdings. As a result the trading prices of the Shares may deviate from the Fund’s NAV. Although it is expected that the market price of Shares will approximate the Fund’s NAV, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount). This risk is heightened in times of market volatility or periods of steep market declines. Any of these factors, among others, may lead to the Shares trading at a premium or discount to NAV.
F/m Falling Interest Rates Strategy ETF | Fixed Income Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Fixed-Income Market Risk. When the Fund invests in fixed income securities, the value of your investment in the Fund will fluctuate with changes in interest rates. Typically, a rise in interest rates causes a decline in the value of fixed income securities owned by the Fund. In general, the market price of fixed income securities with longer maturities or duration will increase or decrease more in response to changes in interest rates than shorter-term securities. Other risk factors include credit risk (the debtor may default), extension risk (an issuer may exercise its right to repay principal on a fixed rate obligation held by the Fund later than expected), and prepayment risk (the debtor may pay its obligation early, reducing the amount of interest payments). These risks could affect the value of a particular investment by the Fund, possibly causing the Fund’s share price and total return to be reduced and fluctuate more than other types of investments.
F/m Falling Interest Rates Strategy ETF | High Portfolio Turnover Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●High Portfolio Turnover Risk. The Fund may incur relatively high portfolio turnover. The active and frequent trading of the Fund’s portfolio securities may result in increased transaction costs to the Fund, including brokerage commissions, dealer mark-ups and other transaction costs, which could reduce the Fund’s return.
F/m Falling Interest Rates Strategy ETF | Income Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Income Risk. The Fund’s income may decline if interest rates fall. This decline in income can occur because the Fund may subsequently invest in lower yielding bonds as bonds in its portfolio mature, are near maturity or are called, or the Fund otherwise needs to purchase additional bonds.
F/m Falling Interest Rates Strategy ETF | Interest Rate Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Interest Rate Risk. Interest rate risk is the risk of losses attributable to changes in interest rates. In general, if prevailing interest rates rise, the values of debt instruments tend to fall, and if interest rates fall, the values of debt instruments tend to rise. Changes in the value of a debt instrument usually will not affect the amount of income the Fund receives from it but will generally affect the value of your investment in the Fund. Changes in interest rates may also affect the liquidity of the Fund’s investments in debt instruments. In general, the longer the maturity or duration of a debt instrument, the greater its sensitivity to changes in interest rates. The Fund is subject to the risk that the income generated by its investments may not keep pace with inflation. Actions by governments and central banking authorities can result in increases or decreases in interest rates, which may negatively affect the value of debt instruments held by the Fund and have a negative impact on the Fund’s performance and NAV. Rising interest rates may prompt redemptions from the Fund, which may force the Fund to sell investments at a time when it is not advantageous to do so, which could result in losses. During periods of very low or negative interest rates, the Fund may be unable to maintain positive returns or pay dividends to Fund shareholders. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, result in heightened market volatility and detract from the Fund’s performance to the extent the Fund is exposed to such interest rates. Additionally, under certain market conditions in which interest rates are low and the market prices for portfolio securities have increased, the Fund may have a very low or even negative yield. A low or negative yield would cause the Fund to lose money in certain conditions and over certain time periods. An increase in interest rates will generally cause the value of securities held by the Fund to decline, may lead to heightened volatility in the fixed-income markets and may adversely affect the liquidity of certain fixed-income investments, including those held by the Fund. The historically low-interest rate environment in recent years heightens the risks associated with rising interest rates.
F/m Falling Interest Rates Strategy ETF | Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Market Risk. The trading prices of securities and other instruments fluctuate in response to a variety of factors. The Fund’s NAV and market price may fluctuate significantly in response to these and other factors including economic, political, financial, public health crises (such as epidemics or pandemics), war, acts of terrorism, recessions or other disruptive events (whether real, expected or perceived) in the local, regional or global markets. These factors could have a significant impact on the Fund and its investments and could result in increased premiums or discounts to the Fund’s NAV. As a result, an investor could lose money over short periods due to short-term market movements or long periods of time during prolonged market downturns.
F/m Falling Interest Rates Strategy ETF | Market Trading Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Market Trading Risk. The Fund faces numerous market trading risks, including the potential lack of an active market for the Shares, losses from trading in secondary markets, and disruption in the creation/redemption process of the Fund. In stressed market conditions, the market for Shares may become less liquid in response to deteriorating liquidity in the markets for the Fund’s portfolio holdings, which may cause a variance in the market price of Shares and their underlying NAV. In addition, an exchange or market may issue trading halts on specific securities or financial instruments. As a result, the ability to trade certain securities or financial instruments may be restricted, which may disrupt the Fund’s creation/redemption process, potentially affect the price at which Shares trade in the secondary market, and/or result in the Fund being unable to trade certain securities or financial instruments at all. In these circumstances, the Fund may be unable to rebalance its portfolio, may be unable to accurately price its investments and/or may incur substantial trading losses. Any of these factors may lead to the Shares trading at a premium or discount to the Fund’s NAV.
F/m Falling Interest Rates Strategy ETF | New Fund Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●New Fund Risk. The Fund is a newly organized management investment company with a limited operating history. In addition, there can be no assurance that the Fund will grow to, or maintain, an economically viable size, in which case the Board of Directors (the “Board”) of The RBB Fund, Inc. (the “Company”) may determine to liquidate the Fund.
F/m Falling Interest Rates Strategy ETF | Operational Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Operational Risk. The Fund is exposed to operational risks arising from a number of factors, including, but not limited to, human error, processing and communication errors, errors of the Fund’s service providers, counterparties or other third parties, failed or inadequate processes and technology or systems failures. The Fund and the Adviser seek to reduce these operational risks through controls and procedures. However, these measures do not address every possible risk and may be inadequate to address these risks.
F/m Falling Interest Rates Strategy ETF | Reinvestment Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Reinvestment Risk. Reinvestment risk is the risk that income from the Fund’s portfolio will decline if and when the Fund reinvests the proceeds from the disposition of its portfolio securities at market interest rates that are below the portfolio’s current earnings rate. A decline in income could negatively affect the market price of the Shares.
F/m Falling Interest Rates Strategy ETF | Risk Of Investing In The United States [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Risk of Investing in the United States. Certain changes in the United States economy, such as when the economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.
F/m Falling Interest Rates Strategy ETF | Securities Lending Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Securities Lending Risk. The Fund may engage in securities lending (i.e., lend portfolio securities to institutions, such as certain broker dealers). Securities lending involves the risk that the Fund may lose money because the borrower of the loaned securities fails to return the securities in a timely manner or at all. The Fund could also lose money in the event of a decline in the value of the collateral provided for loaned securities or a decline in the value of any investments made with cash collateral. These events could also trigger adverse tax consequences for the Fund. The Fund could also experience a loss or delay in the recovery of its securities if the borrowing institution breaches its agreement with the Fund.
F/m Falling Interest Rates Strategy ETF | US Treasury Obligations Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●U.S. Treasury Obligations Risk. While U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. Government, such securities are nonetheless subject to credit risk (i.e., the risk that the U.S. Government may be, or be perceived to be, unable or unwilling to honor its financial obligations, such as making payments). Securities issued or guaranteed by federal agencies or authorities and U.S. Government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. Government. U.S. Treasury obligations may differ from other securities in their interest rates, maturities, times of issuance and other characteristics and may provide relatively lower returns than those of other securities. Similar to other issuers, changes to the financial condition or credit rating of the U.S. government may cause the value of the Fund’s U.S. Treasury obligations to decline.
F/m Falling Interest Rates Strategy ETF | Active Management Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Active Management Risk. The Fund is actively managed using proprietary investment strategies and processes. There can be no guarantee that these strategies and processes will be successful or that the Fund will achieve its investment objective.
F/m Falling Interest Rates Strategy ETF | Cash or Cash Equivalents Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Cash or Cash Equivalents Risk. At any time, the Fund may have significant investments in cash or cash equivalents. When a substantial portion of a portfolio is held in cash or cash equivalents, there is the risk that the value of the cash account, including interest, will not keep pace with inflation, thus reducing purchasing power over time. Additionally, in rising markets, holding cash or cash equivalents may adversely affect the Fund’s performance and the Fund may not achieve its investment objective.
F/m Falling Interest Rates Strategy ETF | Counterparty Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Counterparty Risk. Counterparty risk is the risk that a counterparty to a swap contract or other similar investment instrument may default on its payment obligation to the Fund. Such a default may cause the value of an investment in the Fund to decrease.
F/m Falling Interest Rates Strategy ETF | Derivatives Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Derivatives Risk. A Fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. These risks include (i) the risk that the counterparty to a derivative transaction may not fulfill its contractual obligations; (ii) risk of mispricing or improper valuation; and (iii) the risk that changes in the value of the derivative may not correlate perfectly with the underlying asset, rate or index. Derivative prices are highly volatile and may fluctuate substantially during a short period of time. Such prices are influenced by numerous factors that affect the markets, including, but not limited to: changing supply and demand relationships; government programs and policies; national and international political and economic events, changes in interest rates, inflation and deflation and changes in supply and demand relationships. Trading derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities.
F/m Falling Interest Rates Strategy ETF | Early Close Trading Halt Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Early Close/Trading Halt Risk. An exchange or market may close or issue trading halts on specific securities, or the ability to buy or sell certain securities or financial instruments may be restricted, which may prevent a Fund from buying or selling certain securities or financial instruments. In these circumstances, a Fund may be unable to rebalance its portfolio, may be unable to accurately price its investments and may incur substantial trading losses.
F/m Falling Interest Rates Strategy ETF | Futures Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Futures Risk. Futures are standardized, exchange-traded contracts that obligate a purchaser to take delivery, and a seller to make delivery, of a specific amount of an asset at a specified future date at a specified price. The primary risks associated with the use of futures contracts and options are: (a) the imperfect correlation between the change in market value of the instruments held by the Fund and the price of the futures contract or option; (b) the possible lack of a liquid secondary market for a futures contract and the resulting inability to close a futures contract when desired; (c) losses caused by unanticipated market movements, which are potentially unlimited; (d) the investment adviser’s inability to predict correctly the direction of securities prices, interest rates, currency exchange rates and other economic factors; and (e) the possibility that the counterparty will default in the performance of its obligations.
F/m Falling Interest Rates Strategy ETF | Illiquid Investments Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Illiquid Investments Risk. The possible lack of a liquid secondary market for derivatives and the resulting inability of the Fund to sell or otherwise close a derivatives position could expose the Fund to losses and could make derivatives more difficult for the Fund to value accurately.
F/m Falling Interest Rates Strategy ETF | Issuer Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Issuer Risk. The performance of the Fund depends on the performance of individual securities or other assets to which the Fund has exposure. The value of securities or other assets may decline, or perform differently from the market as a whole, due to changes in the financial condition or credit rating of the issuer or counterparty.
F/m Falling Interest Rates Strategy ETF | Leverage Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Leverage Risk. Using derivatives can create leverage, which can amplify the effects of market volatility on the Fund's share price and make the Fund's returns more volatile. The use of leverage may cause the Fund to liquidate portfolio positions when it would not be advantageous to do so in order to satisfy its obligations. The use of leverage may also cause the Fund to have higher expenses than those of other funds that do not use such techniques.
F/m Falling Interest Rates Strategy ETF | Liquidity Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Liquidity Risk. Certain securities held by the Fund may be difficult (or impossible) to sell at the time and at the price the Adviser would like. As a result, the Fund may have to hold these securities longer than it would like and may forego other investment opportunities. There is the possibility that the Fund may lose money or be prevented from realizing capital gains if it cannot sell a security at a particular time and price.
F/m Falling Interest Rates Strategy ETF | Options Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Options Risk. When the Fund purchases a call option, it receives, in return for the premium it pays, the right to buy from the writer of the option the underlying security at a specified price at any time before the option expires. The Fund purchases call options in anticipation of an increase in the market value of securities that it intends ultimately to buy. During the life of the call option, a Fund is able to buy the underlying security at the exercise price regardless of any increase in the market price of the underlying security. In order for a call option to result in a gain, the market price of the underlying security must exceed the sum of the exercise price, the premium paid, and transaction costs.
F/m Falling Interest Rates Strategy ETF | Over the Counter Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Over-the-Counter Market Risk. Securities and options traded in over-the-counter markets may trade less frequently and in limited volumes and thus exhibit more volatility and liquidity risk, and the prices paid by the Fund in over-the-counter transactions may include an undisclosed dealer markup. The Fund is also exposed to default by the over-the-counter option writer who may be unwilling or unable to perform its contractual obligations to the Fund.
F/m Falling Interest Rates Strategy ETF | Pricing Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Pricing Risk. If market conditions make it difficult to value some investments, the Fund may value these investments using more subjective methods, such as fair value pricing. In such cases, the value determined for an investment could be different from the value realized upon such investment’s sale. As a result, you could pay more than the market value when buying Fund Shares or receive less than the market value when selling Fund Shares.
F/m Falling Interest Rates Strategy ETF | Rate Linked Derivatives Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Rate-Linked Derivatives Risk. The Fund’s exposure to derivatives tied to interest rates subjects the Fund to greater volatility than investments in traditional securities, such as stocks and bonds. Investing in derivatives tied to interest rates, including through options tied to the shape of the U.S. interest rate curve, can be extremely volatile. The value of such investments may fluctuate rapidly based on a variety of factors, including overall market movements; economic events and policies; changes in interest rates or inflation rates; changes in monetary and exchange control programs; war; acts of terrorism; natural disasters; and technological developments. The Fund is expected to benefit from the options it holds if long-term U.S. interest rates rise during the time period in which the Fund holds the options. However, if long-term U.S. interest rates decrease, the Fund will lose money on the options, up to the amount invested in option premiums, and underperform an otherwise identical bond fund that had not used such options. Rate-linked derivatives may lose money if interest rates change in a manner not anticipated by the Adviser. An increase in interest rates may cause the value of securities held directly or indirectly by the Fund to decline to the extent that the Fund’s hedging strategy is not effectively implemented. Even if the Fund is hedged against losses due to long-term interest rate increases linked to U.S. interest rates, outright interest rate increases may also lead to heightened volatility in the fixed-income markets and may positively affect the value of the Fund’s options while negatively impacting the Fund’s investments in U.S. Treasuries. The Fund could lose money on the options held by the Fund, and the present value of the Fund’s portfolio investments could decrease if inflation increases. These interest rate-linked options may also cause the Fund’s net asset value and returns to be more volatile and expose the Fund to increased counterparty risk. Fluctuations in the U.S. interest rate curve or the price of the options owned by the Fund could materially adversely affect an investment in the Fund. The Fund’s investments in options are not intended to mitigate duration and credit risk or other factors influencing the price of U.S. government bonds, which may have a greater impact on the bonds’ returns than interest rate risk. Moreover, to the extent that interest rate risk has been priced into the government bonds owned directly or indirectly by the Fund, the Fund could underperform other investments even during periods of rising long-term U.S. interest rates. There is no guarantee that the Fund will have positive performance even in environments of sharply rising U.S. interest rates. There is no guarantee that the Fund will be able to successfully mitigate interest rate risk.
F/m Falling Interest Rates Strategy ETF | Rating Agencies Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

●Rating Agencies Risk. Ratings are not an absolute standard of quality, but rather general indicators that reflect only the view of the originating rating agencies from which an explanation of the significance of such ratings may be obtained. There is no assurance that a particular rating will continue for any given period of time or that any such rating will not be revised downward or withdrawn entirely if, in the judgment of the agency establishing the rating, circumstances so warrant. A downward revision or withdrawal of such ratings, or either of them, may have an effect on the liquidity or market price of the securities in which the Fund invests.
F/m Falling Interest Rates Strategy ETF | Reverse Repurchase Agreements Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Reverse Repurchase Agreements Risk. Reverse repurchase agreements are a form of secured borrowing and subject the Fund to the risks associated with leverage, including exposure to potential gains and losses in excess of the amount invested, resulting in an increase in the speculative character of the Fund’s outstanding shares. Reverse repurchase agreements involve the risk that the investment return earned by the Fund (from the investment of the proceeds) will be less than the interest expense of the transaction, that the market value of the securities sold by the Fund will decline below the price the Fund is obligated to pay to repurchase the securities, and that the other party may fail to return the securities in a timely manner or at all.
F/m Falling Interest Rates Strategy ETF | Shorting US Treasury Securities Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Shorting U.S. Treasury Securities Risk. The Fund may seek short exposure to financial instruments such as U.S. Treasury securities. There is no guarantee that the returns on the Fund’s short positions will produce positive returns and the Fund could lose money if the short positions produce negative returns. U.S. Treasury prices are highly sensitive to changes in interest rates and a decrease in yields (increase in prices) could result in significant losses for short positions. Shorting typically requires borrowing securities, which involves reliance on the availability of lenders and custodians. The failure of a counterparty to deliver the securities may impact the Fund’s execution of its strategy.
F/m Falling Interest Rates Strategy ETF | Swap Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Swap Risk. Swaps are subject to tracking risk because they may not be perfect substitutes for the instruments they are intended to hedge or replace. Over the counter swaps are subject to counterparty default. Leverage inherent in derivatives will tend to magnify the Fund’s losses.
F/m Falling Interest Rates Strategy ETF | Swaptions Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Swaptions Risk. A “swaption” is a contract that gives a counterparty the right (but not the obligation) to enter into a new swap agreement or to shorten, extend, cancel or otherwise modify an existing swap agreement, at some designated future time on specified terms. The Fund may purchase interest rate payer swaptions. When the Fund purchases a swaption, it risks losing only the amount of the premium it has paid should it decide to let the option expire unexercised.
F/m Falling Interest Rates Strategy ETF | TBA Securities Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●TBA Securities Risk. In a TBA transaction, a seller agrees to deliver a security at a future date, but does not specify the particular security to be delivered. Instead, the seller agrees to accept any security that meets specified terms. TBA transactions involve the risk that the securities received may have less favorable characteristics than what was anticipated when the Fund entered into the transaction. TBA transactions are also subject to counterparty risk and will be exposed to changes in the value of the underlying investments during the term of the agreement.
F/m Falling Interest Rates Strategy ETF | U S Treasury and Agency Market Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●U.S. Treasury and Agency Market Risk. The U.S. Treasury and agency market can be volatile, and the value of instruments correlated with these markets may fluctuate dramatically from day to day. U.S. Treasury and agency obligations may provide relatively lower returns than those of other securities. Similar to other debt instruments, U.S. Treasury and agency obligations are subject to debt instrument risk and interest rate risk. In addition, changes to the financial condition or credit rating of the U.S. Government may cause the value of U.S. Treasury and agency obligations to decline. U.S. Treasury obligations are backed by the “full faith and credit” of the U.S. government and are generally considered to have negligible credit risk. Securities issued or guaranteed by federal agencies or authorities and U.S. government-sponsored instrumentalities or enterprises may or may not be backed by the full faith and credit of the U.S. government.
F/m Falling Interest Rates Strategy ETF | Valuation Risk [Member]  
Prospectus [Line Items] rr_ProspectusLineItems  
Risk [Text Block] rr_RiskTextBlock

 

●Valuation Risk. The prices provided by the Fund’s pricing services or independent dealers or the fair value determinations made by the valuation committee of the Adviser may be different from the prices used by other funds or from the prices at which securities are actually bought and sold. The prices of certain securities provided by pricing services may be subject to frequent and significant change, and will vary depending on the information that is available.
F/m Falling Interest Rates Strategy ETF | F/m Falling Interest Rates Strategy ETF Shares  
Prospectus [Line Items] rr_ProspectusLineItems  
Trading Symbol dei_TradingSymbol UFAL
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.50%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets none
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.50%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 51
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 $ 160
[1] “Other Expenses” have been estimated to reflect expenses to be incurred during the current fiscal year.