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ETFMG Prime Cyber Security ETF

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Investment Objective

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The ETFMG Prime Cyber Security ETF (the “Fund” or the “Cyber Security ETF”) seeks to provide investment results that, before fees and expenses, correspond generally to the total return performance of the Prime Cyber Defense Index (the “Index”).

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Fees and Expenses

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The following table describes the fees and expenses you may pay if you buy, hold, and sell shares of the Fund (“Shares”). This table and the Example below do not include the brokerage commissions and other fees to financial intermediaries that investors may pay on their purchases and sales of Shares.

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

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Portfolio Turnover

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The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes 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. For the fiscal year ended September 30, 2020, the Fund’s portfolio turnover rate was 33% of the average value of its portfolio.

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33.00%

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This table and the Example below do not include the brokerage commissions and other fees to financial intermediaries that investors may pay on their purchases and sales of Shares.

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Example

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This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. This Example does not take into account the brokerage commissions that you may pay on your purchases and sales of Shares.

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Although your actual costs may be higher or lower, based on these assumptions your cost would be:

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Principal Investment Strategies

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The Fund uses a “passive” or indexing approach to try to achieve its investment objective. Unlike many investment companies, the Fund does not try to “beat” the Index and does not seek temporary defensive positions when markets decline or appear overvalued.

The Fund uses a replication strategy. A replication strategy is an indexing strategy that involves investing in the securities of the Index in approximately the same proportions as in the Index. However, the Fund may utilize a representative sampling strategy with respect to the Index when a replication strategy might be detrimental to shareholders, such as when there are practical difficulties or substantial costs involved in compiling a portfolio of equity securities to follow the Index, in instances in which a security in the Index becomes temporarily illiquid, unavailable or less liquid, or as a result of legal restrictions or limitations (such as tax diversification requirements) that apply to the Fund but not the Index.

The Index tracks the performance of the exchange-listed equity securities (or corresponding American Depositary Receipts (“ADRs”) or Global Depositary Receipts (“GDRs”)) of companies across the globe that (i) engage in providing cyber defense applications or services as a vital component of its overall business (“Cyber Defense Architecture Providers”) or (ii) provide hardware or software for cyber defense activities as a vital component of its overall business (“Cyber Defense Application Providers”). Cyber defense refers to products (hardware/software) and services designed to protect computer hardware, software, networks and data from unauthorized access, vulnerabilities, attacks and other security breaches. The categories of Cyber Defense Architecture Providers and Cyber Defense Application Providers are referred to herein as “sectors”.

Companies in the Cyber Defense Architecture Providers and Cyber Defense Application Providers sectors are identified by Prime Indexes (the “Index Provider”), an independent index provider that is not affiliated with the Fund’s investment adviser. The Index Provider utilizes issuer financial statements and other public filings and reports, as well as third-party industry research, reports, and analyses, to identify Cyber Defense Architecture Providers and Cyber Defense Application Providers around the world that meet the Index’s criteria for inclusion.

The Index Provider may exclude companies that meet the criteria for inclusion in the Index or include companies that do not meet such criteria if it determines that including or excluding them would be contrary to the objective of the Index (e.g., their inclusion would negatively affect the investibility of the Index, the company’s economic fortunes are predominantly driven by a business not related to cybersecurity, the company is expected to meet the inclusion criteria in the immediate future and plays an important role in the cybersecurity industry).

The Index has a quarterly review in March, June, September, and December of each year at which times the Index is reconstituted and rebalanced by the Index Provider. The composition of the Index and the constituent weights are determined on the two Thursdays before the second Friday of each March, June, September, and December (or the next business day if this is a non-business day) (the “Selection Day”). Component changes are made after the market close on the third Friday of March, June, September, and December (or the next business day if the third Friday is not a business day) and become effective at the market opening on the next trading day. The Index is developed and owned by the Index Provider, and the Index is calculated and maintained by Solactive AG. The Index Provider is independent of Solactive AG, the Fund, and the Fund’s investment adviser.

Companies meeting the sector criteria are screened as of the Selection Day for investibility (e.g., must not be listed on an exchange in a country which employs certain restrictions on foreign capital investment), a minimum market capitalization of $100 million at the time of selection, and an operating company structure (as opposed to a pass-through security). The Index Provider may include companies in the Index with a market capitalization within 5% of the above threshold as of the Selection Date to account for short term fluctuations in market capitalization resulting from changes in a security’s price.

The Index’s exposure to each sector is based on the cumulative market capitalization of index components within the sector relative to the combined market capitalization of both sectors. Each company within a sector is equally weighted at the time of each rebalance of the Index, subject to the adjustments described below.

The cumulative weight of all constituents with an individual weight of 5% or greater may not in the aggregate account for more than 50% of the weight of the Index as of the Selection Day. Additionally, Index constituents with a market capitalization of less than US $600 million as of the Selection Day will have their weight reduced by 30–35% depending on their specific market capitalization, and constituents with a three-month average daily value traded (“ADTV”) of less than US $2.5 million as of the Selection Day will have their weight reduced by 15–55% depending on their specific ADTV (collectively, the “Liquidity Requirements”). The weight of any individual Index constituent whose weight is reduced due to the Liquidity Requirements will be redistributed pro rata among all other Index constituents whose weights have not been reduced due to the Liquidity Requirements based on the ADTV of such constituents. Additionally, each Index constituent whose weight is reduced due to the Liquidity Requirements will have a maximum weight of 4.5%, and any excess weight above 4.5% will be redistributed pro rata among all other Index constituents based on their weight (after any reductions due to the Liquidity Requirements).

As of January 15, 2021 the Index had 58 constituents, 19 of which were foreign companies, and the three largest stocks and their weightings in the Index were Cisco Systems Inc 3.07%, FireEye, Inc. 2.98%, and Tenable Holdings, Inc. 2.93%.

The Fund invests at least 80% of its total assets, exclusive of collateral held from securities lending, in the component securities of the Index and in ADRs and GDRs based on the component securities in the Index. The Fund may invest up to 20% of its total assets in securities that are not in the Fund’s Index to the extent that the Fund’s adviser believes such investments should help the Fund’s overall portfolio track the Index.

The Fund may lend its portfolio securities to brokers, dealers, and other financial organizations. These loans, if and when made, may not exceed 33 1/3% of the total asset value of the Fund (including the loan collateral). By lending its securities, the Fund may increase its income by receiving payments from the borrower.

The Fund rebalances its portfolio in accordance with its Index, and, therefore, any changes to the Index’s rebalance schedule will result in corresponding changes to the Fund’s rebalance schedule.

Correlation: Correlation is the extent to which the values of different types of investments move in tandem with one another in response to changing economic and market conditions. An index is a theoretical financial calculation, while the Fund is an actual investment portfolio. The performance of the Fund and the Index may vary somewhat due to transaction costs, asset valuations, foreign currency valuations, market impact, corporate actions (such as mergers and spin-offs), legal restrictions or limitations, illiquid or unavailable securities, and timing variances.

The Fund’s investment adviser expects that, over time, the correlation between the Fund’s performance and that of the Index, before fees and expenses, will exceed 95%. A correlation percentage of 100% would indicate perfect correlation. If the Fund uses a replication strategy, it can be expected to have greater correlation to the Index than if it uses a representative sampling strategy.

Industry Concentration Policy: The Fund will concentrate its investments (i.e., hold 25% or more of its net assets) in a particular industry or group of related industries to approximately the same extent that the Index is concentrated. As of January 15, 2021, the Index was concentrated in companies in the software and services industries group.

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The Fund will concentrate its investments (i.e., hold 25% or more of its net assets) in a particular industry or group of related industries to approximately the same extent that the Index is concentrated. As of January 15, 2021, the Index was concentrated in companies in the software and services industries group.

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Principal Risks

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As with all funds, a shareholder is subject to the risk that his or her investment could lose money. The principal risks affecting shareholders’ investments in the Fund are set forth below. An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any government agency.

Cyber Security Companies Risk: Companies in the cyber security field, including companies in the Cyber Defense Architecture Providers and Cyber Defense Application Providers sectors, face intense competition, both domestically and internationally, which may have an adverse effect on profit margins. Cyber security companies may have limited product lines, markets, financial resources or personnel. The products of cyber security companies may face obsolescence due to rapid technological developments and frequent new product introduction, and such companies may face unpredictable changes in growth rates, competition for the services of qualified personnel and competition from foreign competitors with lower production costs. Companies in the cyber security field are heavily dependent on patent and intellectual property rights. The loss or impairment of these rights may adversely affect the profitability of these companies.

Foreign Investment Risk: Returns on investments in foreign stocks could be more volatile than, or trail the returns on, investments in U.S. stocks.

Currency Risk: Indirect and direct exposure to foreign currencies subjects the Fund to the risk that currencies will decline in value relative to the U.S. dollar. Currency rates in foreign countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates and the imposition of currency controls or other political developments in the U.S. or abroad.

Depositary Receipts Risk: The Fund may invest in depositary receipts. Investment in ADRs and GDRs may be less liquid than the underlying shares in their primary trading market and GDRs, many of which are issued by companies in emerging markets, may be more volatile and less liquid than depositary receipts issued by companies in more developed markets.

Emerging Markets Securities Risk: The Fund’s investments may expose the Fund’s portfolio to the risks of investing in emerging markets. Investments in emerging markets are subject to greater risk of loss than investments in developed markets. This is due to, among other things, greater market volatility, lower trading volume, political and economic instability, greater risk of market shutdown and more governmental limitations on foreign investments than typically found in developed markets.

Foreign Market and Trading Risk: The trading markets for many foreign securities are not as active as U.S. markets and may have less governmental regulation and oversight. Foreign markets also may have clearance and settlement procedures that make it difficult for the Fund to buy and sell securities. These factors could result in a loss to the Fund by causing the Fund to be unable to dispose of an investment or to miss an attractive investment opportunity, or by causing Fund assets to be uninvested for some period of time.

Foreign Securities Risk: The Fund invests a significant portion of its assets directly in securities of issuers based outside of the U.S., or in depositary receipts that represent such securities. Investments in securities of non-U.S. issuers involve certain risks that may not be present with investments in securities of U.S. issuers, such as risk of loss due to foreign currency fluctuations or to political or economic instability, as well as varying regulatory requirements applicable to investments in non-U.S. issuers. There may be less information publicly available about a non-U.S. issuer than a U.S. issuer. Non-U.S. issuers may also be subject to different regulatory, accounting, auditing, financial reporting and investor protection standards than U.S. issuers.

Political and Economic Risk: The Fund is subject to foreign political and economic risk not associated with U.S. investments, meaning that political events, social and economic events and natural disasters occurring in a country where the Fund invests could cause the Fund’s investments in that country to experience gains or losses. The Fund also could be unable to enforce its ownership rights or pursue legal remedies in countries where it invests.

Privatization Risk: Several foreign countries in which the Fund invests have begun a process of privatizing certain entities and industries. Privatized entities may lose money or be re-nationalized.

Smaller Companies Risk: The Fund’s Index may be composed primarily of, or have significant exposure to, securities of smaller companies. Smaller companies may be more vulnerable to adverse business or economic events than larger, more established companies, and may underperform other segments of the market or the equity market as a whole. The securities of smaller companies also tend to be bought and sold less frequently and at significantly lower trading volumes than the securities of larger companies. As a result, it may be more difficult for the Fund to buy or sell a significant amount of the securities of a smaller company without an adverse impact on the price of the company’s securities, or the Fund may have to sell such securities in smaller quantities over a longer period of time, which may increase the Fund’s tracking error.

rapid technological developments and frequent new product introduction, and such companies may face unpredictable changes in growth rates, competition for the services of qualified personnel and competition from foreign competitors with lower production costs. Companies in the technology sector are heavily dependent on patent and intellectual property rights. The loss or impairment of these rights may adversely affect the profitability of these companies.

The remaining principal risks are presented in alphabetical order. Each risk summarized below is considered a “principal risk” of investing in the Fund, regardless of the order in which it appears.

Concentration Risk: The Fund’s investments will be concentrated in an industry or group of industries to the extent the Index is so concentrated. To the extent the Fund invests more heavily in particular industries, groups of industries, or sectors of the economy, its performance will be especially sensitive to developments that significantly affect those industries, groups of industries, or sectors of the economy, and the value of Fund shares may rise and fall more than the value of shares that invest in securities of companies in a broader range of industries or sectors.

Equity Market Risk: The equity securities held in the Fund’s portfolio may experience sudden, unpredictable drops in value or long periods of decline in value. This may occur because of factors that affect securities markets generally or factors affecting specific issuers, industries, or sectors in which the Fund invests such as political, market and economic developments, as well as events that impact specific issuers. Additionally, natural or environmental disasters, widespread disease or other public health issues, war, acts of terrorism or other events could result in increased premiums or discounts to the Fund’s NAV.

ETF Risks:

Absence of an Active Market Risk: Although the Fund's shares are approved for listing on the Exchange, there can be no assurance that an active trading market will develop and be maintained for Fund shares. There can be no assurance that the Fund will grow to or maintain an economically viable size, in which case the Fund may experience greater tracking error to its Index than it otherwise would at higher asset levels or the Fund may ultimately liquidate.

Authorized Participants, Market Makers and Liquidity Providers Concentration Risk: The Fund has a limited number of financial institutions that may act as Authorized Participants (“APs”), none of which are obligated to engage in creation and/or redemption transactions. 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 a significantly diminished trading market for Fund shares and 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. The risks associated with limited APs may be heightened in scenarios where APs have limited or diminished access to the capital required to post collateral.

Costs of Buying or Selling Shares Risk: Investors buying or selling Fund shares in the secondary market will pay brokerage commissions or other charges imposed by brokers as determined by the applicable broker. Brokerage commissions are often a fixed amount and may be a significant proportional cost for investors seeking to buy or sell relatively small amounts of shares.

Fluctuation of NAV Risk: The NAV of Fund shares will generally fluctuate with changes in the market value of the Fund’s securities holdings. The market prices of shares will generally fluctuate in accordance with changes in the Fund’s NAV and supply and demand of shares on the Exchange. It cannot be predicted whether Fund shares will trade below, at or above their NAV. During periods of unusual volatility or market disruptions, market prices of Fund shares may deviate significantly from the market value of the Fund’s securities holdings or the NAV of Fund shares. As a result, investors in the Fund may pay significantly more or receive significantly less for Fund shares than the value of the Fund’s underlying securities or the NAV of Fund shares.

Market Trading Risk: An investment in the Fund faces numerous market trading risks, including the potential lack of an active market for Fund shares, losses from trading in secondary markets, periods of high volatility and disruption in the creation/redemption process of the Fund. Any of these factors, among others, may lead to the Fund’s shares trading at a premium or discount to NAV.

Trading Issues Risk: Although Fund shares are listed for trading on the NYSE Arca, Inc. (the “Exchange”), there can be no assurance that an active trading market for such shares will be maintained. Trading in Fund shares may be halted due to market conditions or for reasons that, in the view of the Exchange, make trading in shares inadvisable. There can be no assurance that the requirements of the Exchange necessary to maintain the listing of any Fund will continue to be met or will remain unchanged or that the shares will trade with any volume, or at all. Further, secondary markets may be subject to erratic trading activity, wide bid/ask spreads and extended trade settlement periods in times of market stress because market makers and Authorized Participants may step away from making a market in Fund shares and in executing creation and redemption orders, which could cause a material deviation in the Fund’s market price from its NAV.

Management Risk: While the Fund is not actively managed, the Fund is subject to the risks associated with decisions made by the Fund’s investment adviser if the Fund utilizes a representative sampling strategy or to the extent the Fund’s investment adviser makes decisions regarding the investment of collateral from securities on loan.

Models and Data Risk: The Index relies heavily on proprietary quantitative models as well as information and data supplied by third parties (“Models and Data”). When Models and Data prove to be incorrect or incomplete, any decisions by the Index made in reliance thereon expose the Fund to potential risks as the Fund tracks the Index.

Natural Disaster/Epidemic Risk: Natural or environmental disasters, such as earthquakes, fires, floods, hurricanes, tsunamis and other severe weather-related phenomena generally, and widespread disease, including pandemics and epidemics, have been and may be highly disruptive to economies and markets, adversely impacting individual companies, sectors, industries, markets, currencies, interest and inflation rates, credit ratings, investor sentiment, and other factors affecting the value of the Fund’s investments. Given the increasing interdependence among global economies and markets, conditions in one country, market, or region are increasingly likely to adversely affect markets, issuers, and/or foreign exchange rates in other countries, including the U.S. Any such events could have a significant adverse impact on the value of the Fund’s investments.

Passive Investment Risk: The Fund is not actively managed and therefore would not sell an equity security due to current or projected underperformance of a security, industry or sector, unless that security is removed from the Index. Unlike with an actively managed fund, the Adviser does not use techniques or defensive strategies designed to lessen the effects of market volatility or to reduce the impact of periods of market decline. This means that, based on market and economic conditions, the Fund’s performance could be lower than other types of funds that may actively shift their portfolio assets to take advantage of market opportunities or to lessen the impact of a market decline.

Reliance on Trading Partners Risk: The Fund invests in some economies that are heavily dependent upon trading with key partners. Any reduction in this trading may cause an adverse impact on the economy in which the Fund invests.

Rule 144A Securities Risk: Rule 144A securities are restricted securities that can be purchased only by “qualified institutional buyers,” as defined under the Securities Act. The market for Rule 144A securities typically is less active than the market for publicly-traded securities. As such, investing in Rule 144A securities may reduce the liquidity of the Fund’s investments, and the Fund may be unable to sell the security at the desired time or price, if at all. The purchase price and subsequent valuation of Rule 144A securities normally reflect a discount, which may be significant, from the market price of comparable unrestricted securities for which a liquid trading market exists. A restricted security that was liquid at the time of purchase may subsequently become illiquid and its value may decline as a result. In addition, transaction costs may be higher for restricted securities than for more liquid securities. The Fund may also have to bear the expense of registering the securities for resale and the risk of substantial delays in effecting the registration.

Securities Lending Risk: The Fund may engage in securities lending. The Fund may lose money if the borrower of the loaned securities delays returning in a timely manner or fails to return the loaned securities. Securities lending involves the risk that the Fund could lose money in the event of a decline in the value of collateral provided for loaned securities. In addition, the Fund bears the risk of loss in connection with its investment of the cash collateral it receives from a borrower. To the extent that the value or return of the Fund’s investment of the cash collateral declines below the amount owed to the borrower, the Fund may incur losses that exceed the amount it earned on lending the security.

Tax Risk: To qualify for the favorable tax treatment generally available to regulated investment companies, the Fund must satisfy certain diversification requirements under the Internal Revenue Code of 1986, as amended (the “Code”). In particular, the Fund generally may not acquire a security if, as a result of the acquisition, more than 50% of the value of the Fund’s assets would be invested in (a) issuers in which the Fund has, in each case, invested more than 5% of the Fund’s assets and (b) issuers more than 10% of whose outstanding voting securities are owned by the Fund. When the Index is concentrated in a relatively small number of securities, it may not be possible for the Fund to fully implement a replication strategy or a representative sampling strategy while satisfying these diversification requirements. The Fund’s efforts to satisfy the diversification requirements may cause the Fund’s return to deviate from that of the Index, and the Fund’s efforts to replicate the Index may cause it inadvertently to fail to satisfy the diversification requirements. If the Fund were to fail to qualify as a regulated investment company, it would be taxed in the same manner as an ordinary corporation, and distributions to its shareholders would not be deductible by the Fund in computing its taxable income.

Tracking Error Risk: The Fund’s return may not match or achieve a high degree of correlation with the return of the Index. To the extent the Fund utilizes a sampling approach, it may experience tracking error to a greater extent than if the Fund sought to replicate the Index. In addition, in order to minimize the market impact of an Index rebalance, the Fund may begin trading to effect the rebalance in advance of the effective date of the rebalance and continue trading after the effective date of the rebalance, which may contribute to tracking error.

Valuation Risk: The sales price that the Fund could receive for a security may differ from the Fund’s valuation of the security and may differ from the value used by the Index, particularly for securities that trade in low volume or volatile markets or that are valued using a fair value methodology. In addition, the value of the securities in the Fund’s portfolio may change on days when shareholders will not be able to purchase or sell the Fund’s shares.

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As with all funds, a shareholder is subject to the risk that his or her investment could lose money.

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An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any government agency.

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Performance Information

Performance Information Illustrates Variability of Returns [Text]

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The following information provides some indication of the risks of investing in the Fund. The bar chart shows the annual return for the Fund. The table shows how the Fund’s average annual returns for one year, five years, and since inception compare with those of the Index and a broad measure of market performance. The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future. Updated performance information is available on the Fund’s website at www.etfmg.com or by calling 1‑844‑383‑6477.

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The following information provides some indication of the risks of investing in the Fund.

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1‑844‑383‑6477

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www.etfmg.com

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The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future.

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Calendar Year Total Returns as of December 31,

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During the period of time shown in the bar chart, the Fund’s highest return for a calendar quarter was 23.97% (quarter ended June 30, 2020) and the Fund’s lowest return for a calendar quarter was -19.81% (quarter ended September 30, 2015).

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highest return for a calendar quarter

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Jun. 30, 2020

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23.97%

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lowest return for a calendar quarter

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Sep. 30, 2015

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(19.81%)

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

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Average Annual Total Returns (for the periods ended December 31, 2020)

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(reflects no deduction for fees, expenses or taxes)

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

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Actual after-tax returns depend on your tax situation and may differ from those shown and are not relevant if you hold your shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts.

ETFMG Prime Cyber Security ETF | ISE Cyber Security™ Index / Prime Cyber Defense Index (reflects no deduction for fees, expenses or taxes)

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ISE Cyber Security™ Index / Prime Cyber Defense Index (reflects no deduction for fees, expenses or taxes)1

^[1]

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40.86%

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rr_AverageAnnualReturnYear05

18.34%

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rr_AverageAnnualReturnSinceInception

15.64%

^[1]

ETFMG Prime Cyber Security ETF | S&P 500 Index (reflects no deduction for fees, expenses, or taxes)

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Nov. 11, 2014

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S&P 500 Index (reflects no deduction for fees, expenses or taxes)

rr_AverageAnnualReturnYear01

18.40%

rr_AverageAnnualReturnYear05

15.22%

rr_AverageAnnualReturnSinceInception

12.71%

ETFMG Prime Cyber Security ETF | ETFMG Prime Cyber Security ETF

rr_AverageAnnualReturnInceptionDate

Nov. 11, 2014

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dei_TradingSymbol

HACK

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0.60%

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none

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none

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0.60%

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$ 61

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192

rr_ExpenseExampleYear05

335

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$ 750

Annual Return 2015

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(1.68%)

Annual Return 2016

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3.25%

Annual Return 2017

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19.61%

Annual Return 2018

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6.94%

Annual Return 2019

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23.17%

rr_AnnualReturn2020

40.83%

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Return Before Taxes

rr_AverageAnnualReturnYear01

40.83%

rr_AverageAnnualReturnYear05

18.03%

rr_AverageAnnualReturnSinceInception

15.18%

ETFMG Prime Cyber Security ETF | ETFMG Prime Cyber Security ETF | After Taxes on Distributions

rr_AverageAnnualReturnInceptionDate

Nov. 11, 2014

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Return After Taxes on Distributions

rr_AverageAnnualReturnYear01

40.18%

rr_AverageAnnualReturnYear05

17.84%

ETFMG Prime Cyber Security ETF | ETFMG Prime Cyber Security ETF | After Taxes on Distributions and Sales

rr_AverageAnnualReturnSinceInception

15.03%

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rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

rr_AverageAnnualReturnYear01

24.27%

rr_AverageAnnualReturnYear05

14.58%

ETFMG Prime Junior Silver Miners ETF

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12.34%

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ETFMG Prime Junior Silver Miners ETF

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Investment Objective

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The ETFMG Prime Junior Silver Miners ETF (the “Fund” or the “Junior Silver ETF”) seeks to provide investment results that, before fees and expenses, correspond generally to the total return of the Prime Junior Silver Miners & Explorers Index (the “Index”).

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Fees and Expenses

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

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Portfolio Turnover

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71.00%

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This table and the Example below do not include the brokerage commissions and other fees to financial intermediaries that investors may pay on their purchases and sales of Shares.

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Example

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Although your actual costs may be higher or lower, based on these assumptions your cost would be:

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Principal Investment Strategies

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The Index tracks the performance of the equity securities (or corresponding American Depositary Receipts (“ADRs”) or Global Depositary Receipts (“GDRs”)) of small-capitalization companies actively engaged in silver refining, mining, or exploration (“Junior Silver Companies”). “Junior” is a term used in reference to small capitalization exploration companies. Junior Silver Companies include pure play companies that generate more than 50% of their revenue from silver mining activities and non-pure play companies that generate 50% or less of their revenue from silver mining activities. The stocks are weighted according to a modified market capitalization that is based upon the percentage of company revenues generated from silver mining activities such that, when weighting Junior Silver Companies, the market cap of a pure play company is multiplied by a factor of three and the market cap of a non-pure play company is multiplied by a factor of one. The five stocks with the highest adjusted market capitalization are assigned a weight of 13%, 11%, 9%, 7%, and 5% respectively with all remaining stocks weighted pro rata based on their relative adjusted market capitalization, subject to a cap of 4.5%. The securities of each company in the Index must also be listed on a securities exchange.

The initial universe of Junior Silver Companies is determined based on proprietary research and analysis conducted by Prime Indexes, (the “Index Provider”), an independent index provider that is not affiliated with the Fund’s investment adviser. The Index Provider uses a variety of publicly available resources for such analysis, including financial statements and other reports published by issuers to determine whether a company is actively engaged as a Junior Silver Company.

would negatively affect the investibility of the Index, the company’s economic fortunes are predominantly driven by a business not related to that of a Junior Silver Company, the company is expected to meet the inclusion criteria in the immediate future and plays an important role in the junior silver industry).

Junior Silver Companies are then screened as of the Selection Date for investibility to determine initial inclusion (e.g., must not be listed on an exchange in a country which employs certain restrictions on foreign capital investment), a minimum market capitalization of $20 million, a maximum market capitalization of $3 billion, and an operating company structure (as opposed to a pass-through security). The Index Provider may include companies in the Index with a market capitalization within 5% of the above thresholds as of the Selection Date to account for short term fluctuations in market capitalization resulting from changes in a security’s price.

The weightings of the constituents of the Index are further modified in that the cumulative weight of all constituents with an individual weight of 5% or greater may not in the aggregate account for more than 50% of the weight of the Index as of the Selection Day. Further, the cumulative weight of all components with a market capitalization of less than US $100 million may not in the aggregate account for more than 10% of the weight of the Index as of the Selection Day.

As of January 15, 2021, the Index had 48 constituents, 42 of which were foreign companies. The three largest stocks and their weightings in the Index were Pan American Silver Corp 12.31%, Hecla Mining Co 11.43% and First Majestic Silver Corp 9.57%.

The Fund invests at least 80% of its total assets in the component securities of the Index and in ADRs and GDRs based on the component securities in the Index. The Fund may invest up to 20% of its total assets in securities that are not in the Fund’s Index to the extent that the Fund’s adviser believes such investments should help the Fund’s overall portfolio track the Index.

rr_StrategyPortfolioConcentration

rr_RiskHeading

Principal Risks

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Silver Exploration and Production Industry Concentration Risk: The Fund concentrates its assets in an industry or group of related industries to the extent that the Index is so concentrated. Because the Index is expected to concentrate in the Silver Exploration & Production sub-industry of the Metals & Mining industry (in the Natural Resources/Minerals sector), the Fund’s assets will be concentrated in, and will be more affected by the performance of, that sub-industry than a fund that is more diversified. The profitability of companies in the Silver Exploration & Production sub-industry is related to, among other things, the worldwide price of silver and the costs of extraction and production. Worldwide silver prices may fluctuate substantially over short periods of time, so the Fund’s share price may be more volatile than other types of investments. Companies in the sub-industry may be adversely affected by economic conditions, tax treatment, government regulation and intervention, and world events in the regions in which the companies operate (e.g., expropriation, nationalization, confiscation of assets and property, repatriation of capital, military coups, social unrest). The price of the equity securities of silver mining companies and silver may not always be closely correlated. Investing in a silver company involves certain risks unrelated to an investment in silver as a commodity, including production costs, operational and managerial risk, and the possibility that the company will take measures to hedge or minimize its exposure to the volatility of the market price of silver.

Non-Diversification Risk: Because the Fund is “non-diversified,” it may invest a greater percentage of its assets in the securities of a single issuer or a small number of issuers than if it was a diversified fund. As a result, a decline in the value of an investment in a single issuer or a small number of issuers could cause the Fund’s overall value to decline to a greater degree than if the Fund held a more diversified portfolio. This may increase the Fund’s volatility and have a greater impact on the Fund’s performance.

Foreign Investment Risk: Returns on investments in foreign stocks could be more volatile than, or trail the returns on, investments in U.S. stocks.

Geographic Risk: Funds that are less diversified across countries or geographic regions are generally riskier than more geographically diversified funds and risks associated with such countries or geographic regions may negatively affect the Fund.

Canada-Specific Risk: Because investments in the Silver Exploration & Production sub-industry may be geographically concentrated in Canadian companies or companies that have a significant presence in Canada, investment results could be dependent on the financial condition of the Canadian economy. The Canadian economy is reliant on the sale of natural resources and commodities, which can pose risks such as the fluctuation of prices and the variability of demand for exportation of such products. Changes in spending on Canadian products by the economies of other countries or changes in any of these economies may cause a significant impact on the Canadian economy.

the economy, and the value of Fund shares may rise and fall more than the value of shares that invest in securities of companies in a broader range of industries or sectors.

ETF Risks:

increasing interdependence among global economies and markets, conditions in one country, market, or region are increasingly likely to adversely affect markets, issuers, and/or foreign exchange rates in other countries, including the U.S. Any such events could have a significant adverse impact on the value of the Fund’s investments.

Tax Risk: To qualify for the favorable tax treatment generally available to regulated investment companies, the Fund must satisfy certain diversification requirements under the Internal Revenue Code of 1986, as amended (the “Code”). In particular, the Fund generally may not acquire a security if, as a result of the acquisition, more than 50% of the value of the Fund’s assets would be invested in (a) issuers in which the Fund has, in each case, invested more than 5% of the Fund’s assets and (b) issuers more than 10% of whose outstanding voting securities are owned by the Fund. Given the concentration of the Index in a relatively small number of securities, it may not be possible for the Fund to fully implement a replication strategy or a representative sampling strategy while satisfying these diversification requirements. The Fund’s efforts to satisfy the diversification requirements may cause the Fund’s return to deviate from that of the Index, and the Fund’s efforts to replicate the Index may cause it inadvertently to fail to satisfy the diversification requirements. If the Fund were to fail to qualify as a regulated investment company, it would be taxed in the same manner as an ordinary corporation, and distributions to its shareholders would not be deductible by the Fund in computing its taxable income.

rr_RiskLoseMoney

As with all funds, a shareholder is subject to the risk that his or her investment could lose money.

Risk Nondiversified Status [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any government agency.

rr_RiskNondiversifiedStatus

Because the Fund is “non-diversified,” it may invest a greater percentage of its assets in the securities of a single issuer or a small number of issuers than if it was a diversified fund. As a result, a decline in the value of an investment in a single issuer or a small number of issuers could cause the Fund’s overall value to decline to a greater degree than if the Fund held a more diversified portfolio. This may increase the Fund’s volatility and have a greater impact on the Fund’s performance.

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Performance Information

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceNarrativeTextBlock

The following information provides some indication of the risks of investing in the Fund. The bar chart shows the annual return for the Fund from year to year. The table shows how the Fund’s average annual returns for one year, five years, and since inception compare with those of the Index and a broad measure of market performance. The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future. Updated performance information is available on the Fund’s website at www.etfmg.com or by calling 1‑844‑383‑6477.

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following information provides some indication of the risks of investing in the Fund.

rr_PerformanceAvailabilityPhone

1‑844‑383‑6477

rr_PerformanceAvailabilityWebSiteAddress

www.etfmg.com

rr_PerformancePastDoesNotIndicateFuture

The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future.

rr_BarChartHeading

Calendar Year Total Returns as of December 31

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During the period of time shown in the bar chart, the Fund’s highest return for a calendar quarter was 77.11% (quarter ended June 30, 2020) and the Fund’s lowest return for a calendar quarter was -45.33% (quarter ended March 31, 2020).

rr_HighestQuarterlyReturnLabel

highest return for a calendar quarter

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2020

rr_BarChartHighestQuarterlyReturn

77.11%

rr_LowestQuarterlyReturnLabel

lowest return for a calendar quarter

rr_BarChartLowestQuarterlyReturnDate

Mar. 31, 2020

rr_BarChartLowestQuarterlyReturn

(45.33%)

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

rr_PerformanceTableHeading

Average Annual Total Returns (for the periods ended December 31, 2020)

rr_IndexNoDeductionForFeesExpensesTaxes

(reflects no deduction for fees, expenses or taxes)

^[2]

rr_PerformanceTableUsesHighestFederalRate

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

Performance Table Explanation after Tax Higher

rr_PerformanceTableNotRelevantToTaxDeferred

rr_PerformanceTableExplanationAfterTaxHigher

In some cases, the return after taxes may exceed the return before taxes due to an assumed tax benefit from any losses on a sale of Fund shares at the end of the measurement period.

ETFMG Prime Junior Silver Miners ETF | S&P 500 Index (reflects no deduction for fees, expenses, or taxes)

rr_PerformanceTableClosingTextBlock

After-tax returns are calculated using the highest historical individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on your tax situation and may differ from those shown and are not relevant if you hold your shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts. In some cases, the return after taxes may exceed the return before taxes due to an assumed tax benefit from any losses on a sale of Fund shares at the end of the measurement period.

rr_ProspectusLineItems

rr_AverageAnnualReturnLabel

S&P 500 Index (reflects no deduction for fees, expenses or taxes)

rr_AverageAnnualReturnYear01

18.40%

rr_AverageAnnualReturnYear05

15.22%

rr_AverageAnnualReturnSinceInception

15.20%

ETFMG Prime Junior Silver Miners ETF | ISE Junior Silver (Small Cap Miners/Explorers) Index / Prime Junior Silver Miners & Explorers Index (reflects no deduction for fees, expenses or taxes)

rr_AverageAnnualReturnInceptionDate

Nov. 28, 2012

rr_ProspectusLineItems

rr_AverageAnnualReturnLabel

ISE Junior Silver (Small Cap Miners/Explorers) Index / Prime Junior Silver Miners & Explorers Index1 (reflects no deduction for fees, expenses or taxes)

^[2]

rr_AverageAnnualReturnYear01

33.82%

^[2]

rr_AverageAnnualReturnYear05

29.08%

^[2]

rr_AverageAnnualReturnSinceInception

(0.63%)

^[2]

ETFMG Prime Junior Silver Miners ETF | ETFMG Prime Junior Silver Miners ETF

rr_AverageAnnualReturnInceptionDate

Nov. 28, 2012

rr_ProspectusLineItems

dei_TradingSymbol

SILJ

rr_ManagementFeesOverAssets

0.69%

rr_DistributionAndService12b1FeesOverAssets

none

rr_ExpensesOverAssets

0.69%

rr_ExpenseExampleYear01

$ 70

rr_ExpenseExampleYear03

221

rr_ExpenseExampleYear05

384

rr_ExpenseExampleYear10

$ 859

Annual Return 2013

rr_AnnualReturn2013

(53.06%)

Annual Return 2014

rr_AnnualReturn2014

(11.21%)

Annual Return 2015

rr_AnnualReturn2015

(37.81%)

Annual Return 2016

rr_AnnualReturn2016

139.64%

Annual Return 2017

rr_AnnualReturn2017

(5.54%)

Annual Return 2018

rr_AnnualReturn2018

(28.44%)

Annual Return 2019

rr_AnnualReturn2019

56.26%

rr_AnnualReturn2020

33.46%

rr_AverageAnnualReturnLabel

Return Before Taxes

rr_AverageAnnualReturnYear01

33.46%

rr_AverageAnnualReturnYear05

27.56%

rr_AverageAnnualReturnSinceInception

(1.64%)

ETFMG Prime Junior Silver Miners ETF | ETFMG Prime Junior Silver Miners ETF | After Taxes on Distributions

rr_AverageAnnualReturnInceptionDate

Nov. 28, 2012

rr_ProspectusLineItems

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions

rr_AverageAnnualReturnYear01

32.70%

rr_AverageAnnualReturnYear05

27.08%

ETFMG Prime Junior Silver Miners ETF | ETFMG Prime Junior Silver Miners ETF | After Taxes on Distributions and Sales

rr_AverageAnnualReturnSinceInception

(2.00%)

rr_ProspectusLineItems

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

rr_AverageAnnualReturnYear01

19.76%

rr_AverageAnnualReturnYear05

22.69%

ETFMG Prime Mobile Payments ETF

rr_AverageAnnualReturnSinceInception

(1.42%)

rr_ProspectusLineItems

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ETFMG Prime Mobile Payments ETF

rr_ObjectiveHeading

Investment Objective

rr_ObjectivePrimaryTextBlock

The ETFMG Prime Mobile Payments ETF (the “Fund” or the “Mobile Payments ETF”) seeks to provide investment results that, before fees and expenses, correspond generally to the total return performance of the Prime Mobile Payments Index (the “Index”).

rr_ExpenseHeading

Fees and Expenses

rr_ExpenseNarrativeTextBlock

rr_OperatingExpensesCaption

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

rr_PortfolioTurnoverHeading

Portfolio Turnover

rr_PortfolioTurnoverTextBlock

rr_PortfolioTurnoverRate

19.00%

rr_ExpenseExchangeTradedFundCommissions

This table and the Example below do not include the brokerage commissions and other fees to financial intermediaries that investors may pay on their purchases and sales of Shares.

rr_ExpenseExampleHeading

Example

rr_ExpenseExampleNarrativeTextBlock

rr_ExpenseExampleByYearCaption

Although your actual costs may be higher or lower, based on these assumptions your cost would be:

rr_StrategyHeading

Principal Investment Strategies

rr_StrategyNarrativeTextBlock

The Fund uses a “passive” or indexing approach to try to achieve the Fund’s investment objective. Unlike many investment companies, the Fund does not try to “beat” the Index and does not seek temporary defensive positions when markets decline or appear overvalued.

The Index tracks the performance of the exchange-listed equity securities (or corresponding American Depositary Receipts (“ADRs”) or Global Depositary Receipts (“GDRs”)) of companies across the globe that (i) engage in providing payment processing services or applications, (ii) provide payment solutions, (iii) build or provide payment industry architecture, infrastructure or software, or (iv) provide services as a credit card network (collectively, “Mobile Payment Companies”).

Mobile Payment Companies are identified by Prime Indexes (the “Index Provider”), an independent index provider that is not affiliated with the Fund’s investment adviser. The Index Provider utilizes issuer financial statements and other public filings and reports, as well as third-party industry research, reports, and analyses, to identify Mobile Payment Companies around the world that meet the Index’s criteria for inclusion. Mobile Payment Companies are then screened for investibility (e.g., must not be listed on an exchange in a country which employs certain restrictions on foreign capital investment), a minimum market capitalization of $500 million for new component companies and $100 million for existing component companies, and an operating company structure (as opposed to a pass-through security).

would negatively affect the investibility of the Index, the company’s economic fortunes are predominantly driven by a business not related to that of a Mobile Payments Company, the company is expected to meet the inclusion criteria in the immediate future and plays an important role in the mobile payments industry).

The Index constituents are weighted according to a modified market capitalization weighting methodology. Constituent weightings are “modified” in that each constituent weighting is capped at 6% of the Index and the cumulative weight of all constituents with an individual weight of 5% or greater may not in the aggregate account for more than 50% of the weight of the Index as of the Selection Day. In addition, constituents with a market capitalization of less than US $1 billion as of the Selection Day will have their weight reduced by 55–85% depending on their specific market capitalization. The weight of any individual Index constituent whose weight is reduced due to the above-described limits will be redistributed equally among all other Index constituents whose weights are not in excess of such limits.

As of January 15, 2021, the Index had 43 constituents, 20 of which were foreign companies, and the three largest stocks and their weightings in the Index were PayPal Holdings Inc. 6.44%, Square Inc. 6.38%, and American Express Company 5.71%.

rr_StrategyPortfolioConcentration

rr_RiskHeading

Principal Risks

rr_RiskNarrativeTextBlock

Mobile Payment Companies Risk: Mobile Payment Companies face intense competition, both domestically and internationally, and are subject to increasing regulatory constraints, particularly with respect to fees, competition and anti-trust matters, cybersecurity and privacy. Mobile Payment Companies may be highly dependent on their ability to enter into agreements with merchants and other third parties to utilize a particular payment method, system, software or service, and such agreements may be subject to increased regulatory scrutiny. Additionally, certain Mobile Payment Companies have recently faced increased costs related to class-action litigation challenging such agreements. Such factors may adversely affect the profitability and value of such companies.

Foreign Investment Risk: Returns on investments in foreign stocks could be more volatile than, or trail the returns on, investments in U.S. stocks.

Privatization Risk: Several foreign countries in which the Fund invests have begun a process of privatizing certain entities and industries. Privatized entities may lose money or be re-nationalized.

Technology Companies Risk: Companies in the technology field, including companies in the computers, telecommunications and electronics industries, face intense competition, which may have an adverse effect on profit margins. Technology companies may have limited product lines, markets, financial resources or personnel. The products of technology companies may face obsolescence due to rapid technological developments and frequent new product introduction, and such companies may face unpredictable changes in growth rates, competition for the services of qualified personnel and competition from foreign competitors with lower production costs. Companies in the technology sector are heavily dependent on patent and intellectual property rights. The loss or impairment of these rights may adversely affect the profitability of these companies.

ETF Risks:

rr_RiskLoseMoney

As with all funds, a shareholder is subject to the risk that his or her investment could lose money.

Risk Nondiversified Status [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any government agency.

rr_RiskNondiversifiedStatus

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Performance Information

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceNarrativeTextBlock

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following information provides some indication of the risks of investing in the Fund.

rr_PerformanceAvailabilityPhone

1-844-383-6477

rr_PerformanceAvailabilityWebSiteAddress

www.etfmg.com

rr_PerformancePastDoesNotIndicateFuture

The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future.

rr_BarChartHeading

Calendar Year Total Returns as of December 31,

rr_BarChartClosingTextBlock

During the period of time shown in the bar chart, the Fund’s highest return for a calendar quarter was 31.11% (quarter ended June 30, 2020) and the Fund’s lowest return for a calendar quarter was -24.61% (quarter ended March 31, 2020).

rr_HighestQuarterlyReturnLabel

highest return for a calendar quarter

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2020

rr_BarChartHighestQuarterlyReturn

31.11%

rr_LowestQuarterlyReturnLabel

lowest return for a calendar quarter

rr_BarChartLowestQuarterlyReturnDate

Mar. 31, 2020

rr_BarChartLowestQuarterlyReturn

(24.61%)

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

rr_PerformanceTableHeading

Average Annual Total Returns (for periods ended December 31, 2020)

rr_IndexNoDeductionForFeesExpensesTaxes

(reflects no deduction for fees, expenses or taxes)

^[3]

rr_PerformanceTableUsesHighestFederalRate

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

rr_PerformanceTableNotRelevantToTaxDeferred

ETFMG Prime Mobile Payments ETF | S&P 500 Index (reflects no deduction for fees, expenses, or taxes)

rr_PerformanceTableClosingTextBlock

rr_ProspectusLineItems

rr_AverageAnnualReturnLabel

S&P 500 Index (reflects no deduction for fees, expenses or taxes)

rr_AverageAnnualReturnYear01

18.40%

rr_AverageAnnualReturnYear05

15.22%

rr_AverageAnnualReturnSinceInception

13.42%

ETFMG Prime Mobile Payments ETF | ISE Mobile PaymentsTM Index/Prime Mobile Payments Index

rr_AverageAnnualReturnInceptionDate

Jul. 15, 2015

rr_ProspectusLineItems

rr_AverageAnnualReturnLabel

ISE Mobile PaymentsTM Index/Prime Mobile Payments Index1(reflects no deduction for fees, expenses or taxes)

^[3]

rr_AverageAnnualReturnYear01

34.96%

^[3]

rr_AverageAnnualReturnYear05

23.10%

^[3]

rr_AverageAnnualReturnSinceInception

20.64%

^[3]

ETFMG Prime Mobile Payments ETF | ETFMG Prime Mobile Payments ETF

rr_AverageAnnualReturnInceptionDate

Jul. 15, 2015

rr_ProspectusLineItems

dei_TradingSymbol

IPAY

rr_ManagementFeesOverAssets

0.75%

rr_DistributionAndService12b1FeesOverAssets

none

rr_OtherExpensesOverAssets

none

rr_ExpensesOverAssets

0.75%

rr_ExpenseExampleYear01

$ 77

rr_ExpenseExampleYear03

240

rr_ExpenseExampleYear05

417

rr_ExpenseExampleYear10

$ 930

Annual Return 2016

rr_AnnualReturn2016

4.12%

Annual Return 2017

rr_AnnualReturn2017

36.87%

Annual Return 2018

rr_AnnualReturn2018

1.33%

Annual Return 2019

rr_AnnualReturn2019

41.82%

rr_AnnualReturn2020

34.01%

rr_AverageAnnualReturnLabel

Return Before Taxes

rr_AverageAnnualReturnYear01

34.01%

rr_AverageAnnualReturnYear05

22.38%

rr_AverageAnnualReturnSinceInception

19.90%

ETFMG Prime Mobile Payments ETF | ETFMG Prime Mobile Payments ETF | After Taxes on Distributions

rr_AverageAnnualReturnInceptionDate

Jul. 15, 2015

rr_ProspectusLineItems

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions

rr_AverageAnnualReturnYear01

34.01%

rr_AverageAnnualReturnYear05

22.30%

ETFMG Prime Mobile Payments ETF | ETFMG Prime Mobile Payments ETF | After Taxes on Distributions and Sales

rr_AverageAnnualReturnSinceInception

19.83%

rr_ProspectusLineItems

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

rr_AverageAnnualReturnYear01

20.14%

rr_AverageAnnualReturnYear05

18.39%

ETFMG Sit Ultra Short ETF

rr_AverageAnnualReturnSinceInception

16.36%

rr_ProspectusLineItems

rr_RiskReturnHeading

ETFMG Sit Ultra Short ETF

rr_ObjectiveHeading

Investment Objective

rr_ObjectivePrimaryTextBlock

The ETFMG Sit Ultra Short ETF (the “Fund” or the “Ultra Short ETF”) seeks maximum current income to the extent consistent with preserving capital and maintaining liquidity.

rr_ExpenseHeading

Fees and Expenses

rr_ExpenseNarrativeTextBlock

rr_OperatingExpensesCaption

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

rr_PortfolioTurnoverHeading

Portfolio Turnover

rr_PortfolioTurnoverTextBlock

rr_PortfolioTurnoverRate

132.00%

rr_ExpenseExchangeTradedFundCommissions

This table and the Example below do not include the brokerage commissions and other fees to financial intermediaries that investors may pay on their purchases and sales of Shares.

rr_ExpenseExampleHeading

Example

rr_ExpenseExampleNarrativeTextBlock

rr_ExpenseExampleByYearCaption

Although your actual costs may be higher or lower, based on these assumptions your cost would be:

rr_StrategyHeading

Principal Investment Strategies

rr_StrategyNarrativeTextBlock

The Fund is an actively managed exchange-traded fund (“ETF”) that seeks to achieve its investment objective by investing in a diversified portfolio of high-quality short-term U.S. dollar denominated domestic and foreign debt securities and other instruments.

The Fund will, under normal circumstances, invest primarily in fixed-income securities. These include:

•Commercial paper of domestic and foreign banks and corporations;

•Obligations of domestic and foreign banks and corporations, including both fixed rate and floating rate securities;

•Obligations of the U.S. government or its agencies, instrumentalities or sponsored enterprises;

•Mortgage and other asset-backed securities including automobile and credit card receivables, utilities, equipment trust certificates, railway authorities, single-family rentals, manufactured home loans, home improvement loans, and home equity loans; and

•Repurchase agreements relating to the above instruments.

The Fund invests in investment grade domestic debt obligations (i.e., obligations rated within the top four rating categories by a Nationally Recognized Statistical Rating Organization (“NRSRO”) or of comparable quality as determined by the Fund’s Sub-Adviser (as defined below)).

The Fund is not a money market fund, does not seek to maintain a fixed or stable net asset value of $1, is not subject to the rules that govern the quality, maturity, liquidity, and other features of securities that money market funds may purchase, and does not have the tax advantages of a money market fund.

Sit Fixed Income Advisors II, LLC (“Sit Investment” or the “Sub-Adviser”) may invest in debt obligations of maturities with a dollar weighted average maturity of no more than 3 years and may invest in debt obligations with a maximum maturity of 4 years. During normal market circumstances the average portfolio effective duration for the Fund is expected be more than 2 months, but less than 1 year. The Sub-Adviser attempts to diversify the Fund’s portfolio by holding debt obligations of many different issuers and choosing issuers in a variety of sectors. The Fund is a “diversified” fund, which means that it may not, with respect to 75% of its total assets, invest more than 5% of its total assets in the securities of a single issuer (other than cash and cash items, U.S. government securities or securities of other investment companies) or purchase more than 10% of the outstanding voting securities of an issuer.

In determining which debt obligations to buy for the Fund, the Sub-Adviser attempts to achieve the Fund’s investment objective primarily in three ways:

•Yield curve positioning: The Sub-Adviser selects debt obligations with maturities and yields that it believes have the greatest potential for achieving the Fund’s objectives.

•Sector allocation: The Sub-Adviser invests in debt obligations in those sectors which it believes represent the greatest potential for achieving the Fund’s objectives.

•Security selection: The Sub-Adviser determines which issuers it believes offer the best relative value within each sector and then decides which available debt obligations of that issuer to purchase.

The Fund may also invest in shares of stable value money market funds and ETFs that principally invest in the same types of securities in which the Fund may invest directly.

The Fund is actively-managed and does not seek to track the performance of any particular index.

rr_RiskHeading

Principal Risks

rr_RiskNarrativeTextBlock

Active Management Risk: The Fund may not meet its investment objective based on the success or failure of the Fund’s investment adviser (“ETF Managers Group LLC” or the “Adviser”) or Sub-Adviser to implement investment strategies for the Fund.

Cash Redemption Risk: The Fund’s investment strategy may require it to redeem shares for cash or to otherwise include cash as part of its redemption proceeds. The Fund may be required to sell or unwind portfolio investments to obtain the cash needed to distribute redemption proceeds. This may cause the Fund to recognize a capital gain that it might not have recognized if it had made a redemption in-kind. As a result, the Fund may pay out higher annual capital gain distributions than if the in-kind redemption process was used.

Call Risk: Many bonds may be redeemed (“called”) at the option of the issuer before their stated maturity date. In general, an issuer will call its bonds if they can be refinanced by issuing new bonds which bear a lower interest rate. The Fund would then be forced to invest the unanticipated proceeds at lower interest rates, resulting in a decline in the Fund’s income.

Collateralized Mortgage Obligation Risk: The Fund may invest in collateralized mortgage obligations (“CMOs”), which are a type of mortgage-backed security. CMOs are created by dividing the principal and interest payments collected on a pool of mortgages into several revenue streams (tranches) with different priority rights to portions of the underlying mortgage payments.

Credit Risk: Debt issuers and other counterparties may not honor their obligations or may have their debt downgraded by ratings agencies.

ETF Risks:

Absence of a Prior Active Market: Although the Fund’s shares are approved for listing on the Exchange, there can be no assurance that an active trading market will be maintained for Fund shares. There can be no assurance that the Fund will grow to or maintain an economically viable size, in which case the Fund may experience greater tracking error to its Index than it otherwise would at higher asset levels or the Fund may ultimately liquidate.

and no other entities step forward to perform their functions. The risks associated with limited APs may be heightened in scenarios where APs have limited or diminished access to the capital required to post collateral.

Costs of Buying or Selling Shares: Investors buying or selling Shares in the secondary market will pay brokerage commissions or other charges imposed by brokers, as determined by that broker. Brokerage commissions are often a fixed amount and may be a significant proportional cost for investors seeking to buy or sell relatively small amounts of Shares. In addition, secondary market investors will also incur the cost of the difference between the price at which an investor is willing to buy Shares (the “bid” price) and the price at which an investor is willing to sell Shares (the “ask” price). This difference in bid and ask prices is often referred to as the “spread” or “bid/ask spread.” The bid/ask spread varies over time for Shares based on trading volume and market liquidity and is generally lower if Shares have more trading volume and market liquidity and higher if Shares have little trading volume and market liquidity. Further, a relatively small investor base in the Fund, asset swings in the Fund and/or increased market volatility may cause increased bid/ask spreads. Due to the costs of buying or selling Shares, including bid/ask spreads, frequent trading of Shares may significantly reduce investment results and an investment in Shares may not be advisable for investors who anticipate regularly making small investments.

Fluctuation of NAV: The NAV of Fund shares will generally fluctuate with changes in the market value of the Fund’s securities holdings. The market prices of shares will generally fluctuate in accordance with changes in the Fund’s NAV and supply and demand of shares on the Exchange. It cannot be predicted whether Fund shares will trade below, at or above their NAV. Price differences may be due, in large part, to the fact that supply and demand forces at work in the secondary trading market for shares will be closely related to, but not identical to, the same forces influencing the prices of the securities of the Fund trading individually or in the aggregate at any point in time. The market prices of Fund shares may deviate significantly from the NAV of the shares during periods of market volatility. However, given that shares can be created and redeemed in Creation Units (unlike shares of many closed-end funds, which frequently trade at appreciable discounts from, and sometimes at premiums to, their NAV), the Sub-Adviser believes that large discounts or premiums to the NAV of shares should not be sustained. While the creation/redemption feature is designed to make it likely that Fund shares normally will trade close to the Fund’s NAV, disruptions to creations and redemptions may result in trading prices that differ significantly from the Fund’s NAV. If an investor purchases Fund shares at a time when the market price is at a premium to the NAV of the shares or sells at a time when the market price is at a discount to the NAV of the shares, then the investor may sustain losses.

Trading: Although Shares are listed for trading on the NYSE Arca, Inc. (the “Exchange”) and may be listed or traded on U.S. and non-U.S. stock exchanges other than the Exchange, there can be no assurance that an active trading market for such Shares will develop or be maintained. Trading in Shares may be halted due to market conditions or for reasons that, in the view of the Exchange, make trading in Shares inadvisable. In addition, trading in Shares on the Exchange is subject to trading halts caused by extraordinary market volatility pursuant to Exchange “circuit breaker” rules, which temporarily halt trading on the Exchange when a decline in the S&P 500 Index during a single day reaches certain thresholds (e.g., 7%, 13%, and 20%). Additional rules applicable to the Exchange may halt trading in Shares when extraordinary volatility causes sudden, significant swings in the market price of Shares. There can be no assurance that Shares will trade with any volume, or at all, on any stock exchange. In stressed market conditions, the liquidity of Shares may begin to mirror the liquidity of the Fund’s underlying portfolio holdings, which can be significantly less liquid than Shares. Further, secondary markets may be subject to erratic trading activity, wide bid/ask spreads and extended trade settlement periods in times of market stress because market makers and Authorized Participants may step away from making a market in Fund shares and in executing creation and redemption orders, which could cause a material deviation in the Fund’s market price from its NAV. Decisions by market makers or Authorized Participants to reduce their role or step away from these activities in times of market stress could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying value of the Fund’s portfolio securities and the Fund’s market price. This reduced effectiveness could result in Fund shares trading at a price which differs materially from NAV and also in greater than normal intraday bid/ask spreads for Fund shares. During a “flash crash,” the market prices of the Fund’s shares may decline suddenly and significantly. Such a decline may not reflect the performance of the portfolio securities held by the Fund. Flash crashes may cause Authorized Participants and other market makers to limit or cease trading in the Fund’s shares for temporary or longer periods. Shareholders could suffer significant losses to the extent that they sell shares at these temporarily low market prices.

Extension Risk: When interest rates rise, certain obligations may be paid off by the obligor more slowly than anticipated, causing the value of these securities to fall.

Fixed-Income Instruments Risks: The market price of the Fund’s fixed-income instruments may change, sometimes rapidly or unpredictably, in response to changes in interest rates, factors affecting securities markets generally, and other factors. Generally, when interest rates rise, the values of fixed-income instruments fall, and vice versa. The obligor of a fixed-income instrument may not be able or willing to pay interest or to repay principal when due in accordance with the terms of the associated agreement.

Fixed-income instruments may also be subject to call risk, which is the risk that an issuer may exercise its right to redeem a fixed-income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads, and improvements in the issuer's credit quality). If an issuer calls a security that the Fund has invested in, the Fund may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks, or securities with other, less favorable features.

Floating or Variable Rate Securities Risk: Floating or variable rate securities pay interest at rates that adjust in response to changes in a specified interest rate or reset at predetermined dates (such as the end of a calendar quarter). Securities with floating or variable interest rates are generally less sensitive to interest rate changes than securities with fixed interest rates but may decline in value if their interest rates do not rise as much, or as quickly, as comparable market interest rates. Although floating or variable rate securities are generally less sensitive to interest rate risk than fixed rate securities, they are subject to credit, liquidity and default risk and may be subject to legal or contractual restrictions on resale, which could impair their value.

Foreign Debt Securities Risk: The Fund may invest in U.S. dollar-denominated debt obligations of foreign issuers. Foreign debt obligations are generally determined based on the ultimate parent country of risk which consists of the following four factors: management location, country of primary listing, country of revenue and reporting currency of the issuer. Debt obligations issued by a foreign entity that are subject to a guarantee of a U.S. corporate parent or other U.S. entity are generally not regarded as foreign securities.

Illiquid Securities Risks: The Fund may invest up to 15% of its net assets in illiquid securities. Illiquid securities may be difficult to dispose of at a fair price at the times when the Fund believes it is desirable to do so. Investment of the Fund’s assets in illiquid securities may restrict the Fund’s ability to take advantage of market opportunities. Additionally, the Fund may have to forego all or a portion of the interest earned on a security. Liquidity risk may impact the Fund’s ability to meet shareholder redemptions and as a result, the Fund may be forced to sell securities at inopportune prices.

Large Shareholder Transactions Risk: Shares of the Fund are offered to certain other investment companies, large retirement plans and other large investors. As a result, the Fund is subject to the risk that those shareholders may purchase or redeem a large amount of shares of the Fund. To satisfy such large shareholder redemptions, the Fund may have to sell portfolio securities at times when it would not otherwise do so, which may negatively impact the Fund’s NAV and liquidity. In addition, large purchases of Fund shares could adversely affect the Fund’s performance to the extent that the Fund does not immediately invest cash it receives and therefore holds more cash than it ordinarily would. Large shareholder activity could also generate increased transaction costs and cause adverse tax consequences.

Mortgage- and Asset-Backed Securities Risk: The Fund may invest in U.S. government agency mortgage- and asset-backed securities. Mortgage- and asset-backed securities are subject to interest rate risk. Modest movements in interest rates (both increases and decreases) may quickly and significantly reduce the value of certain types of these securities. When interest rates fall, mortgage- and asset-backed securities may be subject to prepayment risk. When interest rates rise, certain types of mortgage- and asset-backed securities are subject to extension risk. Mortgage- and asset-backed securities can also be subject to the risk of default on the underlying residential or commercial mortgage(s) or other assets.

Municipal Securities Risk: From time to time the Fund may invest a substantial amount of its assets in taxable or tax-exempt municipal securities whose interest is paid solely from revenues of similar projects. If the Fund concentrates its investments in this manner, it assumes the economic risks relating to such projects and this may have a significant impact on the Fund’s investment performance. Municipal securities risks include the ability of the issuer to repay the obligation, the relative lack of information about certain issuers of municipal securities, and the possibility of future legislative changes which could affect the market for and value of municipal securities. Certain municipal securities, including private activity bonds, are not backed by the full faith, credit and taxing power of the issuer. Additionally, if events occur after the security is acquired that impact the security’s tax-exempt status, the Fund and its shareholders could be subject to substantial tax liabilities.

Other Investment Companies Risk: The Fund will incur higher and duplicative expenses when it invests in other investment companies. There is also the risk that the Fund may suffer losses due to the investment practices of the underlying funds. When the Fund invests in other investment companies, the Fund will be subject to substantially the same risks as those associated with the direct ownership of securities held by such investment companies.

Portfolio Turnover Risk: The Fund may buy and sell investments frequently. Such a strategy often involves higher expenses, including brokerage commissions, and may increase the amount of capital gains (in particular, short-term capital gains taxable to shareholders at ordinary income rates) realized by the Fund.

Prepayment Risk: When interest rates decline, fixed income securities with stated interest rates may have the principal paid earlier than expected, requiring the Fund to invest the proceeds at generally lower interest rates.

Rating Agencies Risks: Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. In addition, rating agencies are subject to an inherent conflict of interest because they are often compensated by the same issuers whose securities they grade.

Reinvestment Risk: Income from the Fund’s debt securities portfolios will decline if and when the Fund invest the proceeds from matured, traded or called securities in securities with market interest rates that are below the current earnings rate of the Fund’s portfolio.

Repurchase Agreement Risks: Repurchase agreements typically involve the acquisition by the Fund of fixed-income securities from a selling financial institution such as a bank or broker-dealer. The Fund may incur a loss if the other party to a repurchase agreement is unwilling or unable to fulfill its contractual obligations to repurchase the underlying security.

Reverse Repurchase Agreement Risks: A reverse repurchase agreement is the sale by the Fund of a debt obligation to a party for a specified price, with the simultaneous agreement by the Fund to repurchase that debt obligation from that party on a future date at a higher price. Similar to borrowing, reverse repurchase agreements provide the Fund with cash for investment purposes, which creates leverage and subjects the Fund to the risks of leverage. Reverse repurchase agreements also involve the risk that the other party may fail to return the securities in a timely manner or at all. The Fund could lose money if it is unable to recover the securities and/or if the value of collateral held by the Fund, including the value of the investments made with cash collateral, is less than the value of securities.

Temporary Investment Risk: The Fund may hold cash and/or invest all or a portion of its assets in short-term obligations in response to adverse market, economic or other conditions when the investment management team believes that it is in the best interest of the Fund to pursue such a defensive strategy. The investment management team may, however, choose not to make such temporary investments even in very volatile or adverse conditions. The Fund may not achieve its investment objective when it holds cash or invests its assets in short-term obligations. The Fund also may miss investment opportunities and have a lower total return during these periods.

To-be-announced transactions (“TBAs”) Securities and Rolls Risk: TBA transactions are subject to increased credit risk and increased overall investment exposure. TBA rolls involve the risk that the Fund’s counterparty will be unable to deliver the mortgage-backed securities underlying the TBA roll at the fixed time. If the buyer files for bankruptcy or becomes insolvent, the buyer or its representative may ask for and receive an extension of time to decide whether to enforce the Fund’s repurchase obligation. In addition, the Fund earns interest by investing the transaction proceeds during the roll period. TBA roll transactions may have the effect of creating leverage in the Fund’s portfolio.

U.S. Government Securities Risk: U.S. government securities are not guaranteed against price movement and may decrease in value. Some obligations issued or guaranteed by U.S. government agencies and instrumentalities are supported by the full faith and credit of the U.S. Treasury. Other obligations issued by or guaranteed by federal agencies are supported by the discretionary authority of the U.S. government to purchase certain obligations of the federal agency, while other obligations issued by or guaranteed by federal agencies are supported by the right of the issuer to borrow from the U.S. Treasury. While the U.S. government provides financial support to such U.S. government agencies, no assurance can be given that the U.S. government will always do so because the U.S. government is not so obligated by law.

Valuation Risk: The Fund may hold securities for which prices from pricing services may be unavailable or are deemed unreliable, in which case the Fund’s procedures for valuing investments provide that the sub-adviser shall use the fair value of such securities for valuing investments. There is a risk that the fair value determined by the sub-adviser or the price determined by the pricing service may be different than the actual sale prices of such securities.

rr_RiskLoseMoney

As with all funds, a shareholder is subject to the risk that his or her investment could lose money.

rr_RiskNotInsuredDepositoryInstitution

An investment in the Fund is not a bank deposit and is not insured or guaranteed by the FDIC or any government agency.

rr_BarChartAndPerformanceTableHeading

Performance Information

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceNarrativeTextBlock

The following information provides some indication of the risks of investing in the Fund. The bar chart shows the annual return for the Fund from year to year. The table shows how the Fund’s average annual returns for one year and since inception compare with those of a broad measure of market performance. The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future. Updated performance information is available on the Fund’s website at www.etfmg.com or by calling 1‑844‑383‑6477.

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following information provides some indication of the risks of investing in the Fund.

rr_PerformanceAvailabilityPhone

1‑844‑383‑6477

rr_PerformancePastDoesNotIndicateFuture

The Fund’s past performance, before and after taxes, is not necessarily an indication of how the Fund will perform in the future.

rr_BarChartHeading

Calendar Year Total Return as of December 31

rr_BarChartClosingTextBlock

During the period of time shown in the bar chart, the Fund’s highest return for a calendar quarter was 3.54% (quarter ended June 30, 2020) and the Fund’s lowest return for a calendar quarter was -3.64% (quarter ended March 31, 2020).

rr_HighestQuarterlyReturnLabel

highest return for a calendar quarter

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2020

rr_BarChartHighestQuarterlyReturn

3.54%

rr_LowestQuarterlyReturnLabel

lowest return for a calendar quarter

rr_BarChartLowestQuarterlyReturnDate

Mar. 31, 2020

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

rr_BarChartLowestQuarterlyReturn

(3.64%)

rr_IndexNoDeductionForFeesExpensesTaxes

(reflects no deduction for fees, expenses or taxes)

rr_PerformanceTableUsesHighestFederalRate

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

rr_PerformanceTableNotRelevantToTaxDeferred

ETFMG Sit Ultra Short ETF | Bloomberg Barclays U.S. Treasury Bills Index: 1-3-month Index (reflects no deduction for fees, expenses or taxes)

rr_PerformanceTableClosingTextBlock

rr_ProspectusLineItems

rr_AverageAnnualReturnYear01

0.54%

rr_AverageAnnualReturnSinceInception

0.75%

ETFMG Sit Ultra Short ETF | ETFMG Sit Ultra Short ETF Class

rr_AverageAnnualReturnInceptionDate

Oct. 08, 2019

rr_ProspectusLineItems

dei_TradingSymbol

VALT

rr_ManagementFeesOverAssets

0.30%

Acquired Fund Fees and Expenses

rr_OtherExpensesOverAssets

none

rr_AcquiredFundFeesAndExpensesOverAssets

none

rr_ExpensesOverAssets

0.30%

rr_ExpenseExampleYear01

$ 31

rr_ExpenseExampleYear03

rr_ExpenseExampleYear05

169

rr_ExpenseExampleYear10

$ 381

rr_AnnualReturn2020

0.84%

rr_PerformanceTableHeading

Average Annual Total Returns (for the periods ended December 31, 2020)

rr_AverageAnnualReturnLabel

Return Before Taxes

rr_AverageAnnualReturnYear01

0.84%

rr_AverageAnnualReturnSinceInception

1.17%

ETFMG Sit Ultra Short ETF | ETFMG Sit Ultra Short ETF Class | After Taxes on Distributions

rr_AverageAnnualReturnInceptionDate

Oct. 08, 2019

rr_ProspectusLineItems

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions

rr_AverageAnnualReturnYear01

0.21%

ETFMG Sit Ultra Short ETF | ETFMG Sit Ultra Short ETF Class | After Taxes on Distributions and Sales

rr_AverageAnnualReturnSinceInception

0.55%

rr_ProspectusLineItems

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

rr_AverageAnnualReturnYear01

0.49%

ETFMG Sit Ultra Short ETF | ETFMG Sit Ultra Short ETF Class | Bloomberg Barclays U.S. Treasury Bills Index: 1-3-month Index (reflects no deduction for fees, expenses or taxes)

rr_AverageAnnualReturnSinceInception

0.63%

rr_ProspectusLineItems

rr_AverageAnnualReturnLabel

Bloomberg Barclays U.S. Treasury Bills Index: 1-3-month Index (reflects no deduction for fees, expenses or taxes)

ETFMG Travel Tech ETF

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rr_RiskReturnHeading

ETFMG Travel Tech ETF

rr_ObjectiveHeading

Investment Objective

rr_ObjectivePrimaryTextBlock

The ETFMG Travel Tech ETF (the “Fund” or the “Travel Tech ETF”) seeks to provide investment results that, before fees and expenses, correspond generally to the total return performance of the Prime Travel Technology Index NTR (the “Index”).

rr_ExpenseHeading

Fees and Expenses

rr_ExpenseNarrativeTextBlock

rr_OperatingExpensesCaption

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

rr_PortfolioTurnoverHeading

Portfolio Turnover

rr_PortfolioTurnoverTextBlock

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes 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. For the fiscal period February 12, 2020 (commencement of operations) through September 30, 2020, the Fund’s portfolio turnover rate was 49% of the average value of its portfolio.

rr_PortfolioTurnoverRate

49.00%

rr_ExpenseExchangeTradedFundCommissions

This table and the Example below do not include the brokerage commissions and other fees to financial intermediaries that investors may pay on their purchases and sales of Shares.

rr_ExpenseExampleHeading

Example

rr_ExpenseExampleNarrativeTextBlock

rr_ExpenseExampleByYearCaption

Although your actual costs may be higher or lower, based on these assumptions your cost would be:

rr_StrategyHeading

Principal Investment Strategies

rr_StrategyNarrativeTextBlock

The Fund will use a replication strategy. A replication strategy is an indexing strategy that involves investing in the securities of the Index in approximately the same proportions as in the Index. However, the Fund may utilize a representative sampling strategy with respect to the Index when a replication strategy might be detrimental to shareholders, such as when there are practical difficulties or substantial costs involved in compiling a portfolio of equity securities to follow the Index, in instances in which a security in the Index becomes temporarily illiquid, unavailable or less liquid, or as a result of legal restrictions or limitations (such as tax diversification requirements) that apply to the Fund but not the Index.

Prime Travel Technology Index NTR

The Index tracks the performance of globally exchange-listed equity securities (or corresponding American Depositary Receipts (“ADRs”) or Global Depositary Receipts (“GDRs”)) of companies across the globe that are engaged in “Travel Technology Business”

which is defined as providing technology, via the internet and internet-connected devices such as mobile phones, to facilitate the following activities: travel bookings and reservations, ride sharing and hailing, travel price comparison, and travel advice. Companies with products and services that are primarily engaged in any of the categories of Travel Technology Business are collectively called “Travel Technology Companies.”

The companies included in the Index are identified by Prime Indexes (the “Index Provider”). The Index Provider determines whether a company is a Travel Technology Company based on its assessment of: i) descriptions of a company’s primary business activities in its regulatory filings (e.g., annual reports, financial statements and other public filings), investor presentations, as well as third-party industry research, reports, and analyses; and ii) if a company derives more than 50% of its revenue from Travel Technology Business. The Index Provider screens candidate companies for the Travel Technology Index for investability based on i) must be an equity security of an operating company or an ADR of an operating company; ii) must have a minimum market capitalization of $150 million; iii) must have an average daily trading volume of $250,000 or greater; and iv) must be on an exchange in a country that does not employ restrictions on foreign capital investment.

The Index has a quarterly review in March, June, September, and December of each year upon which the Index is reconstituted and rebalanced by the Index Provider. The composition of the Index and the constituent weights are determined on the two Thursdays before the second Friday of each March, June, September, and December (or the next business day if this is a non-business day) (also known as the “Selection Day”). Component changes are implemented as of the market close on the third Friday of March, June, September, and December (or the next business day if the third Friday is not a business day) and become effective at the market opening on the next trading day.

At the time of each reconstitution, the companies in the Index are weighted using a proprietary weighting methodology (the “Methodology”) that weights the securities based on market capitalization and average daily value traded. The larger and more frequently traded companies, based on the Methodology, will receive a higher score compared to smaller and less frequently traded companies. As of January 15, 2021, the Index had 28 components, 21 of which were foreign companies.

The Index is developed and owned by the Index Provider, and the Index is calculated and maintained by Solactive AG (the “Calculation Agent”). The Index Provider is independent of the Calculation Agent, the Fund, and the Fund’s investment adviser.

Industry Concentration Policy: The Fund will concentrate its investments (i.e., hold more than 25% of its net assets) in a particular industry or group of related industries to approximately the same extent that the Index is concentrated.

rr_StrategyPortfolioConcentration

rr_RiskHeading

Principal Risks

rr_RiskNarrativeTextBlock

The remaining risks are presented in alphabetical order. Each risk summarized below is considered a “principal risk” of investing in the Fund, regardless of the order in which it appears.

Absence of a Prior Active Market: Although the Fund’s shares are approved for listing on the Exchange, there can be no assurance that an active trading market will develop and be maintained for Fund shares. There can be no assurance that the Fund will grow to or maintain an economically viable size, in which case the Fund may experience greater tracking error to its Index than it otherwise would at higher asset levels or the Fund may ultimately liquidate.

ETF Risks:

Authorized Participants (“APs”), Market Makers, and Liquidity Providers Concentration Risk: The Fund has a limited number of financial institutions that 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, 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.

Cash Transactions Risk: While not likely, the Fund may effect its creations and redemptions primarily for cash, rather than in-kind securities. Paying redemption proceeds in cash rather than through in-kind delivery of portfolio securities may require the fund to dispose of or sell portfolio investments at an inopportune time to obtain the cash needed to distribute redemption proceeds. This may cause the Fund to incur certain costs such as brokerage costs, and to recognize gains or losses that it might not have incurred if it had made a redemption in-kind. As a result, the Fund may pay out higher or lower annual capital gains distributions than ETFs that redeem in-kind. In addition, the costs imposed on the Fund will decrease the Fund’ NAV unless the costs are offset by a transaction fee payable by an AP.

Costs of Buying or Selling Shares: Investors buying or selling Fund shares in the secondary market will pay brokerage commissions or other charges imposed by brokers as determined by that broker. Brokerage commissions are often a fixed amount and may be a significant proportional cost for investors seeking to buy or sell relatively small amounts of shares.

Trading Issues: Although Fund shares are listed for trading on the NYSE Arca, Inc. (the “Exchange”), there can be no assurance that an active trading market for such shares will develop or be maintained. Trading in Fund shares may be halted due to market conditions or for reasons that, in the view of the Exchange, make trading in shares inadvisable. There can be no assurance that the requirements of the Exchange necessary to maintain the listing of any Fund will continue to be met or will remain unchanged or that the shares will trade with any volume, or at all. Further, secondary markets may be subject to erratic trading activity, wide bid/ask spreads and extended trade settlement periods in times of market stress because market makers and Authorized Participants may step away from making a market in Fund shares and in executing creation and redemption orders, which could cause a material deviation in the Fund’s market price from its NAV.

Foreign Investment Risk: Returns on investments in foreign stocks could be more volatile than, or trail the returns on, investments in U.S. stocks. Since foreign exchanges may be open on days when the Fund does not price its Shares, the value of the securities in the Fund’s portfolio may change on days when shareholders will not be able to purchase or sell the Shares. Conversely, Shares may trade on days when foreign exchanges are closed. Because securities held by the Fund trade on foreign exchanges that are closed when the Fund’s primary listing exchange is open, the Fund is likely to experience premiums and discounts greater than those of domestic ETFs. Each of these factors can make investments in the Fund more volatile and potentially less liquid than other types of investments.

Depositary Receipts Risk: The Fund may invest in depositary receipts. Investment in depositary receipts may be less liquid than the underlying shares in their primary trading market.

Foreign Securities Risk: The Fund invests a significant portion of its assets directly in securities of issuers based outside of the U.S., or in depositary receipts that represent such securities. Investments in securities of non-U.S. issuers involve certain risks that may not be present with investments in securities of U.S. issuers, such as risk of loss due to foreign currency fluctuations or to political or economic instability. There may be less information publicly available about a non-U.S. issuer than a U.S. issuer. Non-U.S. issuers may also be subject to different accounting, auditing, financial reporting and investor protection standards than U.S. issuers.

Privatization Risk: Several foreign countries in which the Fund invests have begun a process of privatizing certain entities and industries. Privatized entities may lose money or be re-nationalized.

Geographic Investment Risk. To the extent the Fund invests, directly or indirectly, a significant portion of its assets in the securities of companies of a single country or region, it is more likely to be impacted by events or conditions affecting that country or region.

Risks Related to Investing in Western Europe. Most developed countries in Western Europe are members of the European Union (EU), and many are also members of the European Monetary Union (EMU), which requires compliance with restrictions on inflation rates, deficits, and debt levels. Unemployment in certain European nations is historically high and several countries face significant debt problems. These conditions can significantly affect every country in Europe. The euro is the official currency of the EU. Funds that invest in Europe may have significant exposure to the euro and events affecting the euro. Recent market events affecting several of the EU member countries have adversely affected the sovereign debt issued by those countries, and ultimately may lead to a decline in the value of the euro. A significant decline in the value of the euro may produce unpredictable effects on trade and commerce generally and could lead to increased volatility in financial markets worldwide.

In a referendum held in June 2016 (known as “Brexit”), the United Kingdom (“UK”) voted to leave the EU. Although the precise time frame for “Brexit” is uncertain, the UK invoked article 50 of the Lisbon Treaty on March 29, 2017 to withdraw from the EU by March 29, 2019. It is unclear how withdrawal negotiations will be conducted and what the potential consequences may be. Withdrawal is expected to be followed by a transition period during which businesses and others prepare for the new post-Brexit rules to take effect on January 1, 2021. During this period and beyond, the impact on the UK and European economies and the broader global economy could be significant, resulting in negative impacts, such as increased volatility and illiquidity, and potentially lower economic growth on markets in the UK, Europe and globally, which may adversely affect the value of the Fund’s investments.

New Fund Risk: The Fund is a recently organized, diversified management investment company with limited operating history. As a result, prospective investors have a limited track record or history on which to base their investment decision. There can be no assurance that the Fund will grow to or maintain an economically viable size.

Other Investment Companies Risk: The Fund will incur higher and duplicative expenses when it invests in other investment companies such as ETFs. There is also the risk that the Fund may suffer losses due to the investment practices of the underlying funds. When the Fund invests in other investment companies, the Fund will be subject to substantially the same risks as those associated with the direct ownership of securities held by such investment companies. Investments in ETFs are also subject to the following risks: (i) the market price of an ETF’s shares may trade above or below their net asset value; (ii) an active trading market for an ETF’s shares may not develop or be maintained; and (iii) trading of an ETF’s shares may be halted for a number of reasons.

rr_RiskLoseMoney

As with all funds, a shareholder is subject to the risk that his or her investment could lose money.

rr_RiskNotInsuredDepositoryInstitution

An investment in the Fund is not a bank deposit and is not insured or guaranteed by the FDIC or any government agency.

rr_BarChartAndPerformanceTableHeading

Performance Information

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceNarrativeTextBlock

The Fund is new and therefore does not have performance history for a full calendar year. 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 a broad measure of market performance. Updated performance information is available at www.etfmg.com.

rr_PerformanceInformationIllustratesVariabilityOfReturns

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 a broad measure of market performance.

Performance One Year or Less [Text]

rr_PerformanceOneYearOrLess

The Fund is new and therefore does not have performance history for a full calendar year.

ETFMG Travel Tech ETF | ETFMG Travel Tech ETF Class

rr_PerformanceAvailabilityWebSiteAddress

www.etfmg.com

rr_ProspectusLineItems

dei_TradingSymbol

AWAY

rr_ManagementFeesOverAssets

0.75%

rr_DistributionAndService12b1FeesOverAssets

none

Acquired Fund Fees and Expenses

rr_OtherExpensesOverAssets

none

rr_AcquiredFundFeesAndExpensesOverAssets

none

rr_ExpensesOverAssets

0.75%

rr_ExpenseExampleYear01

$ 77

rr_ExpenseExampleYear03

240

rr_ExpenseExampleYear05

417

ETFMG Treatments, Testing and Advancements ETF

rr_ExpenseExampleYear10

$ 930

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ETFMG Treatments, Testing and Advancements ETF

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Investment Objective

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The ETFMG Treatments, Testing and Advancements ETF (the “Fund” or the “Treatments ETF”) seeks to provide investment results that, before fees and expenses, correspond generally to the total return performance of the Prime Treatments, Testing and Advancements Index (the “Index”).

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Fees and Expenses

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

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Portfolio Turnover

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The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes 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. For the fiscal period June 17, 2020 (commencement of operations) through September 30, 2020, the Fund’s portfolio turnover rate was 41% of the average value of its portfolio.

rr_PortfolioTurnoverRate

41.00%

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

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This table and the Example below do not include the brokerage commissions and other fees to financial intermediaries that investors may pay on their purchases and sales of Shares.

rr_OtherExpensesNewFundBasedOnEstimates

Based on estimated amounts for the current fiscal year.

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Example

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Although your actual costs may be higher or lower, based on these assumptions your cost would be:

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Principal Investment Strategies

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The Fund invests at least 80% of its total assets, exclusive of collateral held from securities lending, in the component securities of the Index. The Fund may invest up to 20% of its total assets in securities that are not in the Fund’s Index to the extent that the Fund’s adviser believes such investments should help the Fund’s overall portfolio track the Index. The Fund may also invest in other investment companies that principally invest in the types of instruments allowed by the investment strategies of the Fund.

Prime Treatments, Testing and Advancements Index

The Index tracks the performance of U.S.-listed equity securities or depositary receipts of companies that (i) perform research, development, and commercialization of treatments or vaccines for infectious diseases or (ii) engage in the research, development, manufacturing, and provision of biological tests for patients. Such companies are identified by Prime Indexes (the “Index Provider”), an independent index provider that is not affiliated with the Fund’s investment adviser, based on the rules of the Index.

The Index is comprised of two groups of companies, as described below: “Treatment Companies” and “Testing Companies”. “Treatment Companies” are companies that (i) have one or more vaccines or treatments for infectious diseases in pre-clinical research, in any phase of U.S. Food and Drug Administration clinical trials, or in a commercial stage and (ii) are classified by the North American Industry Classification System as either “Pharmaceutical and Medicine Manufacturing” or “Research and Development in the Physical, Engineering, and Life Sciences”. “Testing Companies” are companies that derive more than 50% of their revenue from the research, development, manufacturing, and provision of biological tests for patients.

To qualify for inclusion in the Index, Treatments Companies and Testing Companies must have an operating company structure (as opposed to being a pass-through security). To be added to the Index, Treatments Companies and Testing Companies must have a minimum market capitalization of US$100 million and an average daily value traded over the prior three month period of $250,000. Companies already included in the Index must have a minimum market capitalization of US$50 million.

The Index has a quarterly review in each March, June, September, and December, at which times the Index is reconstituted and rebalanced by the Index Provider. The composition of the Index and the constituent weights are determined on the two Thursdays before the second Friday of each March, June, September, and December (or the next business day if this is a non-business day). Component changes are made after the market close on the third Friday of each March, June, September, and December (or the next business day if the third Friday is not a business day) and become effective at the market opening on the next trading day.

The five largest constituents with a market capitalization under US$15 billion are each weighted at 6% (30% in the aggregate). The remaining constituents with a market capitalization under US$15 billion are weighted bases on their market capitalization subject to a 4% limit per security. Constituents with a market capitalization of US$15 billion or more will be equally weighted with an aggregate weighting of 10%.

The Index is developed and owned by Prime Indexes, and the Index is calculated and maintained by Solactive AG. The Index Provider is not affiliated with Solactive AG, the Fund, or the Fund’s investment adviser.

As of January 15, 2021, the Index had 28 components, and the five largest stocks and their weightings in the Index were Laboratory Corporation of America Holdings 6.17%, Bio Rad Laboratories Inc. 5.89%, Zai Lab Limited 5.71%, Quest Diagnostics Inc. 5.49%, and Adaptive Biotechnologies Corp. 4.92%.

The Fund will concentrate its investments (i.e., hold more than 25% of its net assets) in a particular industry or group of related industries to approximately the same extent that the Index is concentrated. As of January 15, 2021, the Index was concentrated in the following industries: Pharmaceutical and Medicine Manufacturing and Research and Development in the Physical, Engineering, and Life Sciences.

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Principal Risks

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Treatment Companies and Testing Companies Risk: Treatment Companies and Testing Companies are involved in discovering, developing and commercializing novel drugs or tests with significant market potential. These companies face challenges including pre‑clinical testing and clinical trial stages of development. Clinical trials may be delayed and certain programs may never advance in the clinic or may be more costly to conduct than anticipated. Such companies may be dependent on their ability to secure significant funding for research, development, and commercialization of therapeutics, vaccines, tests, and other health care products or services. If there are delays in obtaining required regulatory and marketing approvals for products, the ability of such companies to generate

revenue may be materially impaired. If regulatory approval is obtained, products will still remain subject to regulatory scrutiny with regulatory authorities having the ability to impose significant restrictions on the indicated uses or marketing. Lastly, even if a licensed product is achieved, such companies may encounter difficulties in manufacturing, product release, shelf life, testing, storage, supply chain management, or shipping.

The remaining risks are presented in alphabetical order. Each risk summarized below is considered a “principal risk” of investing in the Fund, regardless of the order in which it appears.

Depositary Receipts Risk: The Fund may invest in depositary receipts, including American Depositary Receipts (“ADRs”). ADRs are U.S. dollar-denominated receipts representing shares of foreign-based corporations. ADRs are issued by U.S. banks or trust companies, and entitle the holder to all dividends and capital gains that are paid out on the underlying foreign shares. Investment in ADRs may be less liquid than the underlying shares in their primary trading market.

ETF Risks:

Absence of an Active Market: Although the Fund’s shares are approved for listing on the NYSE Arca, Inc. (the “Exchange”), there can be no assurance that an active trading market will develop and be maintained for Fund shares. There can be no assurance that the Fund will grow to or maintain an economically viable size, in which case the Fund may experience greater tracking error to its Index than it otherwise would at higher asset levels or the Fund may ultimately liquidate.

Authorized Participants (“APs”), Market Makers, and Liquidity Providers Concentration: The Fund has a limited number of financial institutions that 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, 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.

Cash Transactions: While not likely, the Fund may effect its creations and redemptions primarily for cash, rather than in-kind securities. Paying redemption proceeds in cash rather than through in-kind delivery of portfolio securities may require the fund to dispose of or sell portfolio investments at an inopportune time to obtain the cash needed to distribute redemption proceeds. This may cause the Fund to incur certain costs such as brokerage costs, and to recognize gains or losses that it might not have incurred if it had made a redemption in-kind. As a result, the Fund may pay out higher or lower annual capital gains distributions than ETFs that redeem in-kind. In addition, the costs imposed on the Fund will decrease the Fund’s NAV unless the costs are offset by a transaction fee payable by an AP.

Market Trading: An investment in the Fund faces numerous market trading risks, including the potential lack of an active market for Fund shares, losses from trading in secondary markets, periods of high volatility and disruption in the creation/redemption process of the Fund. Any of these factors, among others, may lead to the Fund’s shares trading at a premium or discount to NAV.

Trading Issues: Although Fund shares are listed for trading on the Exchange, there can be no assurance that an active trading market for such shares will develop or be maintained. Trading in Fund shares may be halted due to market conditions or for reasons that, in the view of the Exchange, make trading in shares inadvisable. There can be no assurance that the requirements of the Exchange necessary to maintain the listing of any Fund will continue to be met or will remain unchanged or that the shares

will trade with any volume, or at all. Further, secondary markets may be subject to erratic trading activity, wide bid/ask spreads and extended trade settlement periods in times of market stress because market makers and Authorized Participants may step away from making a market in Fund shares and in executing creation and redemption orders, which could cause a material deviation in the Fund’s market price from its NAV.

New Fund Risk: The Fund is a recently organized, non-diversified management investment company with limited operating history. As a result, prospective investors have a limited track record or history on which to base their investment decision. There can be no assurance that the Fund will grow to or maintain an economically viable size.

Passive Investment Risk: The Fund is not actively managed and therefore would not sell an equity security due to current or projected underperformance of a security, industry or sector, unless that security is removed from the Index. Unlike with an actively managed fund, the Fund’s investment adviser does not use techniques or defensive strategies designed to lessen the effects of market volatility or to reduce the impact of periods of market decline. This means that, based on market and economic conditions, the Fund’s performance could be lower than other types of funds that may actively shift their portfolio assets to take advantage of market opportunities or to lessen the impact of a market decline.

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As with all funds, a shareholder is subject to the risk that his or her investment could lose money.

Risk Nondiversified Status [Text]

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An investment in the Fund is not a bank deposit and is not insured or guaranteed by the FDIC or any government agency.

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Performance Information

Performance Information Illustrates Variability of Returns [Text]

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Performance One Year or Less [Text]

rr_PerformanceOneYearOrLess

The Fund is new and therefore does not have performance history for a full calendar year.

ETFMG Treatments, Testing and Advancements ETF | ETFMG Treatments, Testing and Advancements ETF

rr_PerformanceAvailabilityWebSiteAddress

www.etfmg.com

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dei_TradingSymbol

GERM

rr_ManagementFeesOverAssets

0.68%

rr_DistributionAndService12b1FeesOverAssets

none

rr_OtherExpensesOverAssets

none

^[4]

rr_ExpensesOverAssets

0.68%

rr_ExpenseExampleYear01

$ 69