v3.25.2
Investment Risks - F/m Callable Tax-Free Municipal ETF
Sep. 26, 2025
Affiliated Fund Risk  
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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.
Asset Class Risk  
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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.
Call Risk  
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Call Risk. During periods of falling interest rates, an issuer of a callable bond held by the Fund may “call” or repay the security before its stated maturity, and the Fund may have to reinvest the proceeds in securities with lower yields, which would result in a decline in the Fund’s income, or in securities with greater risks or with other less favorable features.
Cash or Cash Equivalents Risk  
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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 objectives.
Concentration Risk  
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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.
Counterparty Risk  
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Counterparty Risk. Counterparty risk is the risk that a counterparty to a financial instrument held by the Fund or by a special purpose or structured vehicle invested in the Fund may become insolvent or otherwise fail to perform its obligations, and the Fund may obtain no or limited recovery of its investment, and any recovery may be significantly delayed. Because the Fund may enter into transactions with a limited number of counterparties, this increases the Fund’s exposure to counterparty credit risk. Further, there is a risk that no suitable counterparties will be willing to enter into, or continue to enter into, transactions with the Fund,  and as a result, the Fund may not be able to achieve its leveraged investment objective or rebalance properly, which may result in significant losses to the Fund, or the Fund may decide to change its leveraged investment objective.
Credit Risk  
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Credit Risk. The value of your investment in the Fund may change in response to changes in the credit ratings of the Fund’s portfolio securities. Generally, investment risk and price volatility increase as a security’s credit rating declines. The Fund’s performance could be hurt if an issuer of a debt security suffers an adverse change in financial condition that results in a payment default, security downgrade or inability to meet a financial obligation. Credit risk is greater for lower-rated securities. Because the issuers of junk bonds may be in uncertain financial health, the prices of their debt securities could be more vulnerable to bad economic news, or even the expectation of bad news, than investment-grade debt securities. Credit ratings may not be an accurate assessment of credit risk.
Cyber Security Risk  
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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 cyberattacks or other cyber-failures.
Duration Risk  
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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. As interest rates rise, the value of a bond will fall in direct proportion to its duration and conversely, as interest rates fall, the value of a bond will increase in direct proportion to its duration. Therefore, the longer a bond’s duration (measured in years), the more sensitive its price will be to interest rate changes.
ETF Risk  
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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, there may be significantly diminished trading in Fund Shares, Fund Shares may trade at a material discount to net asset value (“NAV”), and Fund Shares may 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 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 intended to be listed on The Nasdaq Stock Market LLC, 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.
Fixed-Income Market Risk  
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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, Fund expenses and/or taxable distributions. In addition, the Fund may be subject to risks associated with investments in senior non-preferred bonds (sometimes referred to as a “bail-in bonds”), which are debt securities issued by financial institutions that can be converted into equity securities if such conversion is mandated by a financial institution’s regulatory authority due to the financial institution facing the possibility of bankruptcy. The mandatory conversion of a bail-in bond into an equity security may result in a reduction in value of the security and, if the Fund holds such security when the conversion occurs, the Fund’s performance may be negatively impacted.
Fixed-Income Securities Risk  
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Fixed-Income Securities Risk. Fixed-income securities are subject to the risk of the issuer’s inability to meet principal and interest payments on its obligations (i.e., credit risk) and are subject to price volatility resulting from, among other things, interest rate sensitivity, market perception of the creditworthiness of the issuer, willingness of broker-dealers and other market participants to make markets in the applicable securities, and general market liquidity (i.e., market risk). Lower rated fixed-income securities have greater volatility because there is less certainty that principal and interest payments will be made as scheduled. There is a risk that a lack of liquidity or other adverse credit market conditions may hamper the Fund’s ability to sell the debt securities in which it invests.
High Portfolio Turnover Risk  
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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.
Income Risk  
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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.
Index-Related Risk  
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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.
Inflation Risk  
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Inflation Risk. Inflation risk is the risk that the real value of certain assets or real income from investments (the value of such assets or income after accounting for inflation) will be less in the future as inflation decreases the value of money. Inflation, and investors’ expectation of future inflation, can impact the current value of the Fund’s portfolio, resulting in lower asset values and losses to shareholders. This risk may be elevated compared to historical market conditions because of recent monetary policy measures and the current interest rate environment.
Interest Rate Risk  
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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.
Issuer-Specific Risk  
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Issuer-Specific Risk. The value of an individual security or particular type of security may be more volatile than the market as a whole and may perform differently from the value of the market as a whole.
Leverage Risk  
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Leverage Risk. Borrowing transactions, reverse repurchase agreements, securities lending transactions, and other investment transactions such as when-issued, delayed-delivery, or forward commitment transactions may create investment leverage. If the Fund engages in transactions that have a leveraging effect on the Fund’s investment portfolio, the value of the Fund will be potentially more volatile, and all other risks will tend to be compounded. This is because leverage generally creates investment risk with respect to a larger base of assets than the Fund would otherwise have and so magnifies the effect of any increase or decrease in the value of the Fund’s underlying assets. The use of leverage is considered to be a speculative investment practice and may result in losses to the Fund.
Liquidity Risk  
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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.
Management Risk  
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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 that of the Underlying Index.
Market Risk  
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Market Risk. Economies and financial markets throughout the world are becoming increasingly interconnected, which increases the likelihood that events or conditions in one country or region will adversely impact markets or issuers in other countries or regions. The value of the Fund’s investments may be negatively affected by adverse changes in overall economic or market conditions, such as the level of economic activity and productivity, unemployment and labor force participation rates, inflation or deflation (and expectations for inflation or deflation), interest rates, demand and supply for particular products or resources including labor, and debt levels and credit ratings, among other factors. The adverse market conditions may contribute to an overall economic contraction across entire economies or markets, which may negatively impact the profitability of issuers operating in those economies or markets. The Fund is subject to the risk that geopolitical events will disrupt securities markets and adversely affect global economies and markets. The Fund’s NAV and market price may fluctuate significantly in response to these and other factors, including economic, political, or financial events, public health crises (such as epidemics or pandemics), or other disruptive events (whether real, expected, or perceived) in the U.S. and global markets. The Fund could lose money over short periods due to short-term market movements and over longer periods during more prolonged market downturns. As a result, an investor could lose money over short or long periods of time.
Market Price Risk  
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Market Price Risk. Fund Shares are listed for trading on the Exchange and are bought and sold in the secondary market at market prices. The market prices of Shares will fluctuate, in some cases materially, in response to changes in the NAV and supply and demand for Shares. As a result, the trading prices of Shares may deviate significantly from the NAV during periods of market volatility. The Adviser cannot predict whether Shares will trade above, below or at their NAV. Given the fact that Shares can be created and redeemed in Creation Units (defined below), the Adviser believes that large discounts or premiums to the NAV of Shares should not be sustained in the long-term. If market makers exit the business or are unable to continue making markets in Fund Shares, Shares may trade at a discount to NAV like closed-end fund shares and may even face delisting (that is, investors would no longer be able to trade Shares in the secondary market). Further, while the creation/redemption feature is designed to make it likely that Shares normally will trade close to the value of the Fund’s holdings, disruptions to creations and redemptions, including disruptions at market makers, APs or market participants, or during periods of significant market volatility, may result in market prices that differ significantly from the value of the Fund’s holdings. Although market makers will generally take advantage of differences between the NAV and the market price of Fund Shares through arbitrage opportunities, there is no guarantee that they will do so. In addition, the securities held by the Fund may be traded in markets that close at a different time than the Exchange on which the Fund’s Shares trade. Liquidity in those securities may be reduced after the applicable closing times. Accordingly, during the time when the Exchange is open but after the applicable market closing, fixing or settlement times, bid-ask spreads and the resulting premium or discount to the Shares’ NAV is likely to widen. Further, secondary markets may be subject to irregular trading activity, wide bid-ask spreads and extended trade settlement periods, which could cause a material decline in the Fund’s NAV. The Fund’s investment results are measured based upon the daily NAV of the Fund. Investors purchasing and selling Shares in the secondary market may not experience investment results consistent with those experienced by those APs creating and redeeming Shares directly with the Fund. 
Market Trading Risk  
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Market Trading Risk. The Fund faces numerous market trading risks, including the potential lack of an active market for Fund Shares (including through a trading halt), losses from trading in secondary markets, periods of high volatility, and disruptions in the process of creating and redeeming Fund Shares. Any of these factors, among others, may lead to the Fund’s Shares trading in the secondary market at a premium or discount to NAV or to the intraday value of the Fund’s portfolio holdings. If you buy Fund Shares at a time when the market price is at a premium to NAV or sell Fund Shares at a time when the market price is at a discount to NAV, you may pay significantly more or receive significantly less than the underlying value of the Fund Shares.
Municipal Securities Risk  
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Municipal Securities Risk. Municipal securities can be significantly affected by political or economic changes, including changes made in the law after issuance of the securities, as well as uncertainties in the municipal market related to taxation, legislative changes or the rights of municipal security holders, including in connection with an issuer insolvency. Municipal securities backed by current or anticipated revenues from a specific project or specific assets can be negatively affected by the inability to collect revenues from such projects or assets. Certain municipal securities are issued by entities with limited taxing authority such as school districts, or are dependent on revenue from a particular sector or industry, such as the utilities sector, infrastructure sector, or transportation industry.
New Fund Risk  
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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.
Operational Risk  
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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.
Passive Investment Risk  
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Passive Investment Risk. The Fund is not actively managed and may be affected by a general decline in market segments related to the Underlying Index. The Fund invests in securities included in, or representative of, the Underlying Index, regardless of their investment merits. 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.
Pricing Risk  
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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.
Rating Agencies Risk  
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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.
Reinvestment Risk  
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Reinvestment Risk. Reinvestment risk is the risk that 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.
Reverse Repurchase Agreements Risk  
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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.
Risk of Investing in the U.S.  
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Risk of Investing in the U.S. Certain changes in the U.S. economy, such as when the U.S. economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Fund has exposure.
Securities Lending Risk  
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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 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.
Tax Risk  
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Tax Risk. There is no guarantee that the Fund’s income will be exempt from U.S. federal income taxes and/or the federal AMT. Events occurring after the date of issuance of a municipal bond or after the Fund’s acquisition of a municipal bond may result in a determination that interest on that bond is includable in gross income for federal income tax purposes retroactively to its date of issuance. Such a determination may cause a portion of prior distributions by the Fund to its shareholders to be taxable to those shareholders in the year of receipt. Federal or state changes in income or alternative minimum tax rates or in the tax treatment of municipal bonds may make municipal bonds less attractive as investments and cause them to decline in value.
Tracking Error Risk  
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Tracking Error Risk. The Fund may be subject to tracking error, which is the divergence of the Fund’s performance from that of its Underlying Index. Tracking error may occur because of differences between the securities and other instruments held in the Fund’s portfolio and those included in the corresponding Underlying Index, pricing differences, transaction costs incurred by the Fund, the Fund’s holding of uninvested cash, differences in timing of the accrual of or the valuation of distributions, the requirements to maintain pass-through tax treatment, portfolio transactions carried out to minimize the distribution of capital gains to shareholders, acceptance of custom baskets, changes to the Underlying Index or the costs to the Fund of complying with various new or existing regulatory requirements. This risk may be heightened during times of increased market volatility or other unusual market conditions. Tracking error also may result because the Fund incurs fees and expenses, while its Underlying Index does not.
Underlying Fund Risk  
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Underlying Fund Risk. The Underlying Funds in which the Fund invests are subject to investment advisory and other expenses, which will be indirectly paid by the Fund. Each of the Underlying Funds is subject to its own specific risks, but the Adviser expects the principal investment risks of such Underlying Funds will be similar to the risks of investing in the Fund.
Valuation Risk  
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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.
When-Issued Securities Risk  
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When-Issued Securities Risk. The Fund may purchase securities on a when-issued or forward commitment basis. The purchase price of such securities is typically fixed at the time of the commitment, with delivery and payment taking place in the future. At the time of delivery of the securities, the value may be more or less than the purchase or sale price. Purchase of securities on a when-issued or forward commitment basis may give rise to investment leverage, and may result in increased volatility of the Fund’s NAV. Default by, or bankruptcy of, a counterparty to a when-issued transaction would expose the Fund to possible losses because of an adverse market action, expenses or delays in connection with the purchase or sale of the pools specified in such transaction. The Financial Industry Regulatory Authority, Inc. (“FINRA”) Rules impose mandatory margin requirements for certain types of when-issued or forward commitment transactions, with limited exceptions. Such transactions require mandatory collateralization, which may increase the cost of such transactions and impose added operational complexity.
Risk Lose Money [Member]  
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Risk [Text Block] 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.
Risk Nondiversified Status [Member]  
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Non-Diversification Risk. The Fund is a non-diversified investment company, which means it may invest a greater percentage of its assets in a single asset class than a diversified investment company. This may make the value of the Fund’s Shares more susceptible to certain risks than shares of a diversified investment company. As a non-diversified fund, the Fund may have a greater potential to realize losses upon the occurrence of adverse events affecting a particular issuer.