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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To pursue its goal, the fund normally invests substantially all of its assets in equity securities comprising the Morningstar^®Emerging Markets Large Cap Index^SM, depositary receipts based on securities comprising the index, exchange-traded funds (ETFs) providing exposure to such securities, and derivatives with economic characteristics similar to such securities or the index. The fund’s derivatives investments may include futures, currency forwards, total return swaps and structured notes.

The Morningstar^®Emerging Markets Large Cap Index^SMis a float-adjusted market capitalization weighted index designed to measure the performance of emerging market large-capitalization stocks. A country is considered emerging if: (i) its annual per capita gross national income does not fall in the World Bank’s high-income category for the most recent three years; (ii) it has had broad-based discriminatory controls against non-domiciled investors during the most recent three years; and (iii) its stock markets do not exhibit any of the following characteristics: transparency, market regulation, operational efficiency, and the absence of broad-based investment restrictions. The index’s initial universe of eligible securities includes equity securities (including common stock, preferred stock and shares of real estate investment trusts (REITs)), issued by emerging market companies and traded on a major foreign exchange. At each reconstitution, the initial universe is screened to exclude securities based on the number of non-trading days, trading volume and turnover during the preceding six-month period, and market capitalization. Securities not previously part of the last reconstitution are excluded from a current reconstitution if the security has 20 or more non-trading days during the last six months or their trading volume and turnover ranks in the bottom 25% of the initial universe as determined by the index provider based on the preceding six months of trade data. Securities previously part of the last reconstitution are provided a one-time buffer and not excluded unless the security has 30 or more non-trading days (20 or more non-trading days after the one-time buffer) during the last six months or their trading volume and turnover ranks in the bottom 20% (bottom 25% after the one-time buffer) of the initial universe as determined by the index provider based on the preceding six months of trade data. Of the remaining securities, the index includes large capitalization securities from each eligible country, targeting the top 70% of stocks by market capitalization from each eligible country. The index rebalances quarterly in March, June, September and December, and reconstitutes semi-annually in June and December. As of December 31, 2019, the index was comprised of 524 securities.

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. In addition, a significant portion of the fund’s assets will generally be focused in a country or region to the extent the index is focused in a particular country or region. As of December 31, 2019, 27.01% of the index consisted of securities of issuers in the financials sector, with 20.26% of the index consisting of securities of issuers in the banking industry subcategory of the financials sector. As of December 31, 2019, the index had significant exposure to issuers located in China and the Asian region.

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.

• Risks of stock investing. Stocks generally fluctuate more in value than bonds and may decline significantly over short time periods. There is the chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising prices and falling prices. The market value of a stock may decline due to general market conditions or because of factors that affect the particular company or the company’s industry.

• 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.

• Large-cap stock risk. The fund may underperform funds that invest primarily in the stocks of lower quality, smaller capitalization companies during periods when the stocks of such companies are in favor. Compared to small- and mid-capitalization companies, large-capitalization companies may be less responsive to changes and opportunities affecting their business. In addition, large-capitalization companies may be subject to greater regulation than small- and mid-capitalization companies. A company with a large market capitalization relative to the market in a particular country or region may not have a large capitalization relative to the market in another country or region or the global market generally.

• 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. 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. Investments denominated in foreign currencies are subject to the risk that such currencies will decline in value relative to the U.S. dollar and affect the value of these investments held by the fund. 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.

• Emerging market risk. The securities of issuers located or doing substantial business in emerging market countries tend to be more volatile and less liquid than the securities of issuers located in countries with more mature economies. There may be less information publicly available about an emerging market issuer than about a developed market issuer and/or the available information may be outdated or unreliable. In addition, emerging market issuers may not be subject to accounting, auditing, legal and financial reporting standards comparable to those in developed markets. Emerging markets generally have less diverse and less mature economic structures and less stable political systems than those of developed countries. Investments in these countries may be subject to political, economic, legal, market and currency risks. The risks may include less protection of property rights and uncertain political and economic policies, the imposition of capital controls and/or foreign investment limitations by a country, nationalization of businesses and the imposition of sanctions by other countries, such as the United States. These risks may impact the correlation between fund and index performance.

• Foreign currency risk. Investments in foreign currencies are subject to the risk that those currencies will decline in value relative to the U.S. dollar or, in the case of hedged positions, that the U.S. dollar will decline relative to the currency being hedged. Currency exchange rates may fluctuate significantly over short periods of time. Foreign currencies are also subject to risks caused by inflation, interest rates, budget deficits and low savings rates, political factors and government intervention and controls.

• China risk. The fund’s investments are significantly exposed to issuers located in China, and therefore the fund may be particularly exposed to the economy, industries, securities and currency markets of China. The Chinese economy and markets may be adversely affected by protectionist trade policies, slow economic activity in other Asian countries or worldwide, political and social instability, environmental events and natural disasters, regional and global conflicts, terrorism and war, including actions that are contrary to the interests of the United States. China’s economy may be dependent on the economies of other Asian countries, many of which are developing countries. In addition, the current political climate and the further escalation of a trade war between China and the United States may have an adverse effect on both the U.S. and Chinese economies, as each country has imposed tariffs on the other country’s products. From time to time, and as recently as January 2020, China has experienced outbreaks of infectious illnesses, and the country may be subject to other public health threats, infectious illnesses, diseases or similar issues in the future. Any spread of an infectious illness, public health threat or similar issue could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and generally have a significant impact on the Chinese economy, which in turn could adversely affect the fund’s investments.

• Asian risk. The fund invests significantly in stocks issued by companies located in Asian countries. Many Asian countries can be characterized as either emerging or newly industrialized economies and tend to experience more volatile economic cycles than developed countries. Asian economies are also frequently subject to the risks of undeveloped financial service sectors, high inflation, frequent currency fluctuations, devaluations, or restrictions, political and social instability, corruption, and less efficient markets. Economies of Asian countries may also be heavily dependent on international trade and can be adversely affected by trade barriers, exchange controls and other measures imposed or negotiated by the countries with which they trade. Some economies in this region are dependent on a range of commodities, including oil, natural gas and coal. Accordingly, they are strongly affected by international commodity prices and particularly vulnerable to any weakening in global demand for these products. Adverse economic conditions or developments in neighboring countries may increase investors’ perception of the risk of investing in the region as a whole, which may adversely impact the market value of the securities issued by companies in the region. Companies in Asia may be subject to risks such as nationalization or other forms of government interference. Increased political and social unrest could adversely affect the performance of investments in this region.

• Concentration risk. The fund will concentrate its investments (i.e., invest more than 25% its total assets) in a particular industry or group of industries to approximately the same extent that the index is concentrated. To the extent the fund concentrates in a particular industry or group of industries, it will be more susceptible to economic conditions and risks affecting those industries.

• Financials sector risk. Companies in the financials sector are subject to extensive governmental regulation which may limit both the amounts and types of loans and other financial commitments they can make, the interest rates and fees they can charge, the scope of their activities, the prices they can charge and the amount of capital they must maintain. Profitability is largely dependent on the availability and cost of capital funds and can fluctuate significantly when interest rates change or due to increased competition. In addition, deterioration of the credit markets generally may cause an adverse impact in a broad range of markets, thereby affecting a wide range of financial institutions and markets. Certain events in the financial services sector may cause an unusually high degree of volatility in the financial markets and cause certain financial services companies to incur large losses.

• Banking companies risk. The performance of bank stocks may be affected by extensive governmental regulation which may limit both the amounts and types of loans and other financial commitments they can make, and the interest rates and fees they can charge and the amount of capital they must maintain. Profitability is largely dependent on the availability and cost of capital funds, and can fluctuate significantly when interest rates change. Credit losses resulting from financial difficulties of borrowers can negatively impact banking companies. Banks may also be subject to severe price competition. Competition is high among banking companies and failure to maintain or increase market share may result in lost market value.

• ADR risk. ADRs may be subject to certain of the risks associated with direct investments in the securities of foreign companies, such as currency risk, political and economic risk and market risk, because their values depend on the performance of the non-dollar denominated underlying foreign securities. Certain countries may limit the ability to convert ADRs into the underlying foreign securities and vice versa, which may cause the securities of the foreign company to trade at a discount or premium to the market price of the related ADR.

• ETF risk. To the extent the fund invests in ETFs, the fund will be affected by the investment policies, practices and performance of such entities in direct proportion to the amount of assets the fund has invested therein. The risks of investing in other ETFs typically reflect the risks associated with the types of instruments in which the investment companies invest. When the fund invests in an ETF, shareholders of the fund will bear indirectly their proportionate share of the expenses of the ETF (including management fees) in addition to the expenses of the fund. ETFs are exchange-traded investment companies that are, in many cases, designed to provide investment results corresponding to an index. The value of the underlying securities can fluctuate in response to activities of individual companies or in response to general market and/or economic conditions.

• REIT risk. Investments in REITs expose the fund to risks similar to investing directly in real estate. REITs are characterized as equity REITs, mortgage REITs and hybrid REITs, which combine the characteristics of both equity and mortgage REITs. Equity REITs, which may include operating or finance companies, own real estate directly and the value of, and income earned by, the REITs depends upon the income of the underlying properties and the rental income they earn. Equity REITs also can realize capital gains (or losses) by selling properties that have appreciated (or depreciated) in value. Mortgage REITs can make construction, development or long-term mortgage loans and are sensitive to the credit quality of the borrower. Mortgage REITs derive their income from interest payments on such loans. Hybrid REITs generally hold both ownership interests and mortgage interests in real estate. The value of securities issued by REITs is affected by tax and regulatory requirements and by perceptions of management skill. They also may be affected by general economic conditions and are subject to heavy cash flow dependency, defaults by borrowers or tenants, self-liquidation at an economically disadvantageous time, and the possibility of failing to qualify for favorable tax treatment under applicable U.S. or foreign law and/or to maintain exempt status under the 1940 Act.

• Preferred stock risk. Preferred stock is a class of a capital stock that typically pays dividends at a specified rate. Preferred stock is generally senior to common stock, but subordinate to debt securities, with respect to the payment of dividends and on liquidation of the issuer. The market value of preferred stock generally decreases when interest rates rise and is also affected by the issuer’s ability to make payments on the preferred stock.

• 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.

• 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. Certain derivatives in which the fund may invest may reference the London Interbank Offered Rate (LIBOR). On July 27, 2017, the United Kingdom’s Financial Conduct Authority, which regulates LIBOR, announced that it intends to phase out LIBOR by the end of 2021. There remains uncertainty regarding the future of LIBOR and the nature of any replacement rate. While some instruments may contemplate a scenario where LIBOR is no longer available by providing for an alternative rate setting methodology, not all instruments may have such provisions and there is uncertainty regarding the effectiveness of any alternative methodology. The replacement and/or discontinuation of LIBOR could lead to significant short-term and long-term uncertainty and market instability. The unavailability and/or discontinuation of LIBOR could have adverse impacts on derivatives that reference LIBOR, may affect the value, liquidity or return on such derivatives, as they may fall out of favor, and may result in costs incurred by the fund in connection with closing out positions and entering into new positions. Any pricing adjustments to a fund’s investments resulting from a substitute reference rate may also adversely affect the fund’s performance and/or NAV.

• 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.

• Currency forward risk. Currency forward contracts are derivative instruments pursuant to a contract with a counterpar-ty to buy or sell a specific currency at a future date at a price set at the time of the contract. Not all forward contracts require a counterparty to post collateral, which may expose the fund to greater losses in the event of a default by a counterparty. Foreign currency forward transactions include risks associated with fluctuations in foreign currency.

• 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).

• 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. Investments that are illiquid or that trade in lower volumes may be more difficult to value. Investments in foreign securities, particularly those of issuers located in emerging markets, tend to have greater exposure to liquidity risk than domestic securities.

• 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.

• 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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0.11%

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Expense Example, with Redemption, 3 Years

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35

Expense Example, No Redemption, 3 Years

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$ 35