Risk/Return:

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Investment Objective

Expense [Heading]

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Fees and Expenses

Operating Expenses Caption [Text]

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

Portfolio Turnover [Text Block]

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The fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover 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. The fund is new and does not yet have a portfolio turnover rate to disclose.

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

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“Other expenses” are based on estimated amounts for the current fiscal year.

Expense Example Narrative [Text Block]

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The Example is intended to help you compare the cost of investing in the 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 your investment has a 5% return each year and that 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 Narrative [Text Block]

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The fund uses a rules-based, systematic investment strategy that seeks to track an index designed to measure the performance of the high yield bond market. To pursue its goal, the fund normally invests substantially all of its assets in bonds comprising the Bloomberg Barclays US Corporate High Yield Total Return Index and derivatives with economic characteristics similar to such bonds or the index. The fund’s derivatives investments may include credit default swap indexes, total return swaps, structured notes and futures.

The Bloomberg Barclays US Corporate High Yield Total Return Index is designed to measure the U.S. dollar-denominated, high yield (junk), fixed-rate, taxable corporate bond market. Bonds included in the index must have $150 million or more par amount outstanding and at least one year until final maturity. Bonds are classified as high yield if the middle rating of Moody’s, Fitch and S&P is Ba1/BB+/BB+ or below. 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 may not be available, the index provider may use other sources to classify securities by credit quality. The index may include U.S. dollar-denominated bonds issued by foreign issuers. Securities in the index are updated on the last business day of each month. The fund seeks to maintain a dollar-weighted average maturity consistent with that of the index. As of December 31, 2019, the index was comprised of approximately 1,900 securities and had a dollar-weighted average maturity of 5.8 years.

Under normal circumstances, in seeking to track the index’s performance, the fund generally purchases a representative sample of the securities comprising the index. By using a sampling process, the fund typically will not invest in all of the securities in the index. The fund may also fully replicate the index when determined to be in the best interest of the fund in pursuing its objective.

In seeking to track the index, the fund’s assets may be concentrated in (i.e., more than 25% of the fund’s assets invested in) an industry or group of industries, but only to the extent that the index concentrates in a particular industry or group of industries. As of December 31, 2019, 20.97% of the index consisted of securities of issuers in the industrial communications industry.

The fund is classified as diversified under the Investment Company Act of 1940, as amended (1940 Act); however, the fund may become non-diversified solely as a result of a changes in the composition of the index (e.g., changes in weightings of one or more component securities). When the fund is non-diversified, it may invest a relatively high percentage of its assets in a limited number of issuers.

Risk Narrative [Text Block]

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An investment in the fund is not a bank deposit. It is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency. It is not a complete investment program. The fund’s share price fluctuates, sometimes dramatically, which means you could lose money.

• 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 company, 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).

• Interest rate risk. Prices of bonds and other fixed rate fixed-income securities tend to move inversely with changes in interest rates. Typically, a rise in rates will adversely affect fixed-income securities and, accordingly, will cause the value of the fund’s investments in these securities to decline. During periods of very low interest rates, which occur from time to time due to market forces or actions of governments and/or their central banks, including the Board of Governors of the Federal Reserve System in the U.S., the fund may be subject to a greater risk of principal decline from rising interest rates. When interest rates fall, the fund’s investments in new securities may be at lower yields and may reduce the fund’s income. The magnitude of these fluctuations in the market price of fixed-income securities is generally greater for securities with longer effective maturities and durations because such instruments do not mature, reset interest rates or become callable for longer periods of time. Duration is an indication of an investment’s “interest rate risk,” or how sensitive a bond or the fund’s portfolio may be to changes in interest rates. The change in the value of a fixed-income security or portfolio can be approximated by multiplying its duration by a change in interest rates.

• Credit risk. Failure of an issuer of a security to make timely interest or principal payments when due, or a decline or perception of a decline in the credit quality of the security, can cause the security’s price to fall. The lower a security’s credit rating, the greater the chance that the issuer of the security will default or fail to meet its payment obligations.

• High yield securities risk. High yield (junk) securities involve greater credit risk, including the risk of default, than investment grade securities, and are considered predominantly speculative with respect to the issuer’s ability to make principal and interest payments. The prices of high yield securities can fall in response to bad news about the issuer or its industry, or the economy in general, to a greater extent than those of higher rated securities.

• Indexing strategy risk. The fund uses an indexing strategy. It does not attempt to manage market volatility, use defensive strategies or reduce the effects of any long-term periods of poor index performance. The correlation between fund and index performance may be affected by the fund’s expenses, changes in securities markets, changes in the composition of the index and the timing of purchases and redemptions of fund shares. Outdated or unreliable market information could result in errors in index data, index computations or the construction of the index in accordance with its methodology 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.

• Index sampling risk. The use of sampling techniques by the sub-adviser, Mellon, may result in the fund holding a smaller number of securities than are in the index. The sampling techniques used by the sub-adviser to select the securities in which the fund invests may not track the index the same as if the fund were replicating the index and may result in investment performance that differs from the index.

• Foreign investment risk. To the extent the fund invests in foreign securities, the fund’s performance will be influenced by political, social and economic factors affecting investments in foreign issuers. Special risks associated with investments in foreign issuers include exposure to currency fluctuations, less liquidity, less developed or less efficient trading markets, lack of comprehensive company information, political and economic instability and differing auditing and legal standards. To the extent securities held by the fund trade in a market that is closed when the exchange on which the fund’s shares trade is open, there may be deviations between the current price of a security and the last quoted price for the security in the closed foreign market. These deviations could result in the fund experiencing premiums or discounts greater than those of ETFs that invest in domestic securities.

• Privately-issued securities risk. Privately-issued securities, including those that are normally purchased pursuant to Rule 144A or Regulation S promulgated under the 1933 Act, are securities that have not been registered under the 1933 Act and as a result may be subject to legal restrictions on resale. Privately-issued securities are generally not traded on established markets. As a result of the absence of a public trading market, privately issued securities may be deemed to be illiquid investments, may be more difficult to value than publicly traded securities and may be subject to wide fluctuations in value. Delay or difficulty in selling such securities may result in a loss to the fund.

• Industrial communications companies risk. Companies in the industrial communications industry, which includes providers of fiber-optic, fixed-line, cellular and wireless communications networks as well as cable, satellite, and television broadcasting and certain gaming products and networking platforms, may be more likely to be affected by industry competition, substantial capital requirements, government regulation, cyclicality of revenues and earnings, obsolescence of communications products and services due to technological advancement, a potential decrease in the discretionary income of targeted individuals and changing consumer tastes and interests.

• Liquidity risk. When there is little or no active trading market for specific types of securities, it can become more difficult to sell the securities in a timely manner at or near their perceived value. In such a market, the value of such securities and the fund’s share price may fall dramatically, even during periods of declining interest rates. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Investments in foreign securities tend to have greater exposure to liquidity risk than domestic securities.

• Issuer risk. A security’s market value may decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s products or services, or factors that affect the issuer’s industry, such as labor shortages or increased production costs and competitive conditions within an industry.

• Portfolio turnover risk. The fund may engage in frequent trading of its portfolio securities in connection with index rebalancing, which could produce higher transaction costs and taxable distributions, and lower the fund’s after-tax performance.

• Derivatives risk. A small investment in derivatives could have a potentially large impact on the fund’s performance. The use of derivatives involves risks different from, or possibly greater than, the risks associated with investing directly in the underlying assets, and the fund’s use of derivatives may result in losses to the fund. Derivatives in which the fund may invest can be highly volatile, illiquid and difficult to value, and there is the risk that changes in the value of a derivative held by the fund will not correlate with the underlying assets or the fund’s other investments in the manner intended. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment, and involve greater risks than the underlying assets because, in addition to general market risks, they are subject to liquidity risk (lack of a liquid secondary market), credit and counterparty risk (failure of the counterparty to the derivatives transaction to honor its obligation) and pricing risk (risk that the derivative cannot or will not be accurately valued). Future rules and regulations of the Securities and Exchange Commission (SEC) may require the fund to alter, perhaps materially, its use of derivatives.

• Credit default swap index risk. Credit default swap indexes (CDXs) are derivative contracts that reflect the performance of an index of credit default swaps and transfer credit exposure between two parties (for example, between an exchange and the fund). The use of CDXs involves investment techniques and risks different from those associated with ordinary portfolio security transactions, such as potentially heightened counterparty, concentration and exposure risks. Further, the fund’s return from investment in a CDX may not match the return of the referenced index of credit default swaps and could result in losses if the referenced index of credit default swaps does not perform as expected. Unexpected changes in the composition of the index of credit default swaps may also affect performance of the CDX. If a referenced index of credit default swaps has a dramatic intraday move that causes a material decline in the fund’s net assets, the terms of the fund’s CDX may permit the counterparty to immediately close out the transaction. In that event, the fund may be unable to enter into another CDX or otherwise achieve desired exposure, even if the referenced index of credit default swaps reverses all or a portion of its intraday move.

• Structured notes risk. Structured notes, a type of derivative instrument, can be volatile, and the possibility of default by the financial institution or counterparty may be greater for these instruments than for other types of derivative instruments. Structured notes typically are purchased in privately negotiated transactions from financial institutions and, thus, an active trading market for such instruments may not exist.

• Total return swap risk. A total return swap is a contract in which one party agrees to make periodic payments to another party based on the change in market value of the assets underlying the contract, which may include a specified security, basket of securities, or securities indices during the specified period, in return for periodic payments based on a fixed or variable interest rate or the total return from other underlying assets. Total return swap agreements may be used to obtain exposure to a security or market without owning or taking physical custody of such security or investing directly in such market. Total return swap agreements may effectively add leverage to the fund’s portfolio because, in addition to its total net assets, the fund would be subject to investment exposure on the notional amount of the swap. The primary risks associated with total returns swaps are credit risks (if the counterparty fails to meet its obligations) and market risk (if there is no liquid market for the agreement or unfavorable changes occur to the underlying asset).

• Futures risk. The value of a futures contract tends to increase and decrease in correlation with the value of the underlying instrument. Risks of futures contracts may arise from an imperfect correlation between movements in the price of the futures and the price of the underlying instrument. The fund’s use of futures contracts exposes the fund to leverage risk because of the small margin requirements relative to the value of the futures contract. A relatively small market movement will have a proportionately larger impact on the funds that the fund has deposited or will have to deposit with a broker to maintain its futures position. While futures contracts are generally liquid instruments, under certain market conditions they may become illiquid. Futures exchanges may impose daily or intraday price change limits and/ or limit the volume of trading. Additionally, government regulation may further reduce liquidity through similar trading restrictions. As a result, the fund may be unable to close out its futures contracts at a time that is advantageous. The price of futures can be highly volatile; using them could lower total return, and the potential loss from futures could exceed the fund’s initial investment in such contracts.

• Fluctuation of net asset value, share premiums and discounts risk. As with all exchange-traded funds, fund shares may be bought and sold in the secondary market at market prices. The trading prices of fund shares in the secondary market may differ from the fund’s daily net asset value per share and there may be times when the market price of the shares is more than the net asset value per share (premium) or less than the net asset value per share (discount). This risk is heightened in times of market volatility or periods of steep market declines.

• Market risk. The value of the securities in which the fund invests may be affected by political, regulatory, economic and social developments, and developments that impact specific economic sectors, industries or segments of the market. In addition, turbulence in financial markets and reduced liquidity in equity, credit and/or fixed income markets may negatively affect many issuers, which could adversely affect the fund. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. These risks may be magnified if certain events or developments adversely interrupt the global supply chain; in these and other circumstances, such risks might affect companies worldwide. Recent examples include pandemic risks related to COVID-19 and aggressive measures taken worldwide in response by governments, including closing borders, restricting international and domestic travel, and the imposition of prolonged quarantines of large populations, and by businesses, including changes to operations and reducing staff. The effects of COVID-19 have contributed to increased volatility in global markets and will likely affect certain countries, companies, industries and market sectors more dramatically than others. The COVID-19 pandemic has had, and any other outbreak of an infectious disease or other serious public health concern could have, a significant negative impact on economic and market conditions and could trigger a prolonged period of global economic slowdown. To the extent the fund may overweight its investments in certain countries, companies, industries or market sectors, such positions will increase the fund’s exposure to risk of loss from adverse developments affecting those countries, companies, industries or sectors.

• Non-diversification risk. To the extent the fund becomes non-diversified, the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, when the fund is non-diversified, the fund’s performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than when the fund’s invested assets are diversified.

• New fund risk. The fund is newly organized with limited operating history and there can be no assurance that the fund will grow to or maintain sufficient assets to achieve investment and trading efficiencies.

Risk Nondiversified Status [Text]

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To the extent the fund becomes non-diversified, the fund may invest a relatively high percentage of its assets in a limited number of issuers. Therefore, when the fund is non-diversified, the fund’s performance may be more vulnerable to changes in the market value of a single issuer or group of issuers and more susceptible to risks associated with a single economic, political or regulatory occurrence than when the fund’s invested assets are diversified.

Bar Chart and Performance Table [Heading]

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Performance

Performance One Year or Less [Text]

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The fund does not have a full calendar year of performance. Once the fund has completed a full calendar year of operations, a bar chart and table will be included that will provide some indication of the risks of investing in the fund by showing the variability of the fund’s returns and comparing the fund’s performance to its benchmark index.

Performance Past Does Not Indicate Future [Text]

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The fund’s performance is not necessarily indicative of how the fund will perform in the future.

Risk/Return:

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Distribution and service (12b-1) fees

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none

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Total annual fund operating expenses

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0.22%

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Expense Example, with Redemption, 3 Years

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71

Expense Example, No Redemption, 3 Years

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$ 71