Objective, Primary [Text Block]

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Risk/Return [Heading]

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Roundhill BITKRAFT Esports & Digital Entertainment ETF

Objective [Heading]

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Investment Objective

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The Roundhill BITKRAFT Esports & Digital Entertainment ETF (“Esports ETF” or the “Fund”) seeks to track the total return performance, before fees and expenses, of the Roundhill BITKRAFT Esports Index (the “Index”).

Expense [Heading]

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Fees and Expenses of the Fund

Expense Narrative [Text Block]

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This table describes the fees and expenses that you may pay if you buy, sell, and hold shares of the Fund (“Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and Example below.

Shareholder Fees Caption [Text]

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Shareholder Fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

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

Portfolio Turnover [Heading]

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Portfolio Turnover

Portfolio Turnover [Text Block]

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The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Shares are held in a taxable account. These costs, which are not reflected in the Total Annual Fund Operating Expenses or in the Example, affect the Fund’s performance. For the fiscal year ended December 31, 2020, the Fund’s portfolio turnover rate was 93% of the average value of its portfolio.

Portfolio Turnover, Rate

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93.00%

Expense Exchange Traded Fund Commissions [Text]

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You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and Example below.

Expense Example [Heading]

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Example

Expense Example Narrative [Text Block]

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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. The Example does not take into account brokerage commissions that you may pay on your purchases and sales of Shares.

Expense Example by, Year, Caption [Text]

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

Strategy [Heading]

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Principal Investment Strategies

Strategy Narrative [Text Block]

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The Fund uses a “passive management” (or indexing) approach to seek to track the total return performance, before fees and expenses, of the Index. The Index was developed by Roundhill Financial Inc., the Fund’s investment adviser and index provider (“Roundhill” or the “Adviser”), which tracks the performance of a tiered weight portfolio of globally-listed equity securities of companies that are actively involved in the esports and other digital entertainment industries.

Roundhill BITKRAFT Esports Index

The Index tracks the performance of the common stock (or corresponding American Depositary Receipts (“ADRs”) or Global Depositary Receipts (“GDRs”)) of exchange-listed companies that earn revenue from electronic sports, or esports-related business activities, including: (a) video game publishing, (b) video game development, (c) video game streaming platforms, (d) organizing video game tournaments and/or events, (e) operating and/or owning video game leagues, (f) owning competitive video game teams, and (g) gaming hardware and technology companies (collectively, the “Esports Industry”) or whose principal business activity is classified as that of another digital entertainment business activity, such as broadcasting, interactive home entertainment, interactive media & services, technology hardware storage or technology hardware, storage and peripherals. The companies in the Index are segregated into three categories by a committee comprised of staff from Roundhill (the “Committee”), specifically:

(i)“Pure-Play” Companies - Companies whose primary business model and/or growth prospects are directly linked to the Esports Industry. For these companies, continued growth in the Esports Industry is expected to be critical to their economic success going forward.

(ii)“Core” Companies - Companies with substantial operations and/or growth prospects linked to the Esports Industry. These companies have other digital entertainment business units driving their economics, and thus are less affected by the growth of Esports Industry than pure-play companies. In time, growth in the industry and/or investments in their esports units may lead these companies to become pure-play companies if their esports operations become a primary

driver of economic performance. In most cases, the esports related offerings of these companies are core components of the Esports Industry.

(iii)“Non-Core” Companies - Companies with operations and/or growth prospects linked to the Esports Industry. These companies derive the majority of their revenue from digital entertainment business lines not directly related to the Esports Industry. In time, growth in the industry and/or investments in their esports units may lead these companies to become “core” companies if their esports operations become a relevant driver of economic performance. It is unlikely, based on current information, that the esports related offerings of non-core companies would become the primary driver of such economic performance going forward.

The composition of the Index is based on the following rules:

The Index will consist of a minimum of 25 components upon each rebalancing.

When adding new constituents to the Index, an ADR or GDR is included in the Index in lieu of the foreign security if the ADR or GDR has a higher six-month average daily trading value than the foreign security. In the case of an existing component security, the security will not be replaced in the event the corresponding ADR, GDR or foreign security, as applicable, experiences a higher six-month average daily trading value than the existing component security.

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 Roundhill. Component changes resulting from reconstitutions are made after the market close on the third Friday in each quarterly review month and become effective at the market opening on the next trading day.

The Committee is responsible for overseeing implementation of the Index methodology. In overseeing the implementation of the methodology, the Committee will generally follow criteria for the screening, classification, and weighting process, but may adjust the inputs to or outputs from such criteria in instances in which the Committee determines that due to extenuating circumstances or unusual market conditions the results of the process do not result in an appropriate representation of a company within the Index or would be contrary to investor expectations for the Index. For example, the Committee may determine to adjust a company’s weighting in the Index in the event that the information obtained from a company’s public filing and used as part of the process to calculate the company’s weighting in the Index was artificially inflated in the calculation period due to an extraordinary event. In addition, the Committee may determine, at a given rebalance, that a company which had previously been classified as “non-core” and thus included in the Index, has since had a material change to its overall business that justifies moving the company to “N/A” and not including the company in the Index at that time. The Committee’s goal in making these decisions is to maintain the Index’s representation of pure-play companies involved in esports. Members of the Committee can recommend changes to the methodology and submit them to the Committee for approval.

As of March 31, 2021, the Index had 32 constituents. Significant portions of the Index were comprised of companies located in China and the U.S., although this may change from time to time.

The Fund’s Investment Strategy

The Fund invests, under normal circumstances, at least 80% of its net assets (plus borrowings for investment purposes) in companies that are economically tied to esports and other digital entertainment industries. For purposes of the foregoing policy, a company is considered economically tied to the esports industry if it earns revenue from the Esports Industry. A company is considered economically tied to other digital entertainment industries if its principal business activity is classified in one of the following sub-industries: broadcasting, interactive home entertainment, interactive media & services, technology hardware storage or technology hardware, storage and peripherals.

The Fund will generally use a “replication” strategy to achieve its investment objective, meaning the Fund generally will invest in all of the component securities of the Index in approximately the same proportions as in the Index. However, the Fund may use a “representative sampling” strategy, meaning it may invest in a sample of the securities in the Index whose risk, return, and other characteristics closely resemble the risk, return, and other characteristics of the Index as a whole, when Exchange Traded Concepts, LLC (the “Sub-Adviser”), the Fund’s sub-adviser, believes it is in the best interests of the Fund (e.g., when replicating the Index involves practical difficulties or substantial costs, an Index constituent becomes temporarily illiquid, unavailable, or less liquid, or as a result of legal restrictions or limitations that apply to the Fund but not to the Index).

The Fund generally may invest up to 20% of its total assets (exclusive of any collateral held from securities lending) in securities or other investments not included in the Index, but which the Sub-Adviser believes will help the Fund track the Index. For example, the Fund may invest in securities that are not components of the Index to reflect various corporate actions and other changes to the Index (such as reconstitutions, additions, and deletions).

To the extent the Index concentrates (i.e., holds more than 25% of its total assets) in the securities of a particular industry or group of related industries, the Fund will concentrate its investments to approximately the same extent as the Index. As of March 31, 2021, the Index was concentrated in one or more industries in the communication services sector.

Risk [Heading]

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Principal Investment Risks

Risk Narrative [Text Block]

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The principal risks of investing in the Fund are summarized below. The principal risks are presented in alphabetical order to facilitate finding particular risks and comparing them with those of other funds. Each risk summarized below is considered a “principal risk” of investing in the Fund, regardless of the order in which it appears. As with any investment, there is a risk that you could lose all or a portion of your investment in the Fund. Some or all of these risks may adversely affect the Fund’s net asset value (“NAV”), trading price, yield, total return and/or ability to meet its objective. The following risks could affect the value of your investment in the Fund:

•Competitive Esports Risk. Esports companies face intense competition, both domestically and internationally, may have limited product lines, markets, financial resources, or personnel, may have products that face rapid obsolescence, and are heavily dependent on the protection of patent and intellectual property rights. Such factors may adversely affect the profitability and value of esports companies. These companies also may be subject to increasing regulatory constraints, particularly with respect to cybersecurity and privacy. In addition to the costs of complying with such constraints, the unintended disclosure of confidential information, whether because of an error or a cybersecurity event, could adversely affect the reputation, profitability and value of these companies.

•Communication Services Sector Risk. The Fund’s assets will have significant exposure to the communication services sector, which means the Fund will be more affected by the performance of the communication services sector than a fund that is more diversified. Market or economic factors impacting communication services companies and companies that rely heavily on technological advances could have a major effect on the value of the Fund’s investments. The value of stocks of communication services companies and companies that rely heavily on technology is particularly vulnerable to research and development costs, substantial capital requirements, product and services obsolescence, government regulation, and domestic and international competition, including competition from foreign competitors with lower production costs. Stocks of communication services companies and companies that rely heavily on technology, especially those of smaller, less-seasoned companies, tend to be more volatile than the overall market. Additionally, companies in the communication services sector may face dramatic and often unpredictable changes in growth rates and competition for the services of qualified personnel. While all companies may be susceptible to network security breaches, certain companies in the communication services sector may be particular targets of hacking and potential theft of proprietary or consumer information or disruptions in service, which could have a material adverse effect on their businesses.

•Concentration Risk. Because the Fund’s assets will be concentrated in an industry or group of industries to the extent the Index concentrates in a particular industry or group of industries, the Fund is subject to loss due to adverse occurrences that may affect that industry or group of industries.

•Currency Exchange Rate Risk. The Fund may invest in investments denominated in non-U.S. currencies or in securities that provide exposure to such currencies. Changes in currency exchange rates and the relative value of non-U.S. currencies will affect the value of the Fund’s investment and the value of your Shares. Currency exchange rates can be very volatile and can change quickly and unpredictably. As a result, the value of an investment in the Fund may change quickly and without warning and you may lose money.

•Cybersecurity Risk. Cybersecurity incidents may allow an unauthorized party to gain access to Fund assets, customer data (including private shareholder information), or proprietary information, or cause the Fund, the Adviser, the Sub-Adviser and/or other service providers (including custodians, transfer agents and financial intermediaries) to suffer data breaches or data corruption. Additionally, cybersecurity failures or breaches of the electronic systems of the Fund, the Adviser, the Sub-Adviser or the Fund's other service providers, market makers, Authorized Participants or the issuers of securities in which the Fund invests have the ability to cause disruptions and negatively impact the Fund's business operations, potentially resulting in financial losses to the Fund and its shareholders. In an extreme case, a shareholder’s ability to redeem Fund shares may be affected.

•Depositary Receipt Risk. Depositary receipts, including ADRs, involve risks similar to those associated with investments in foreign securities, such as changes in political or economic conditions of other countries and changes in the exchange rates of foreign currencies. Depositary receipts listed on U.S. exchanges are issued by banks or trust companies, and entitle the holder to all dividends and capital gains that are paid out on the underlying foreign shares (“Underlying Shares”). When the Fund invests in depositary receipts as a substitute for an investment directly in the Underlying Shares, the Fund is exposed to the risk that the depositary receipts may not provide a return that corresponds precisely with that of the Underlying Shares. Because the Underlying Shares trade on foreign exchanges that may be closed when the Fund’s primary listing exchange is open, the Fund may experience premiums and discounts greater than those of funds without exposure to such Underlying Shares.

•Emerging Markets Risk. The Fund may invest in companies organized in emerging market nations. Investments in securities and instruments traded in developing or emerging markets, or that provide exposure to such securities or markets, can involve additional risks relating to political, economic, or regulatory conditions not associated with investments in U.S. securities and instruments or investments in more developed international markets. Such conditions may impact the ability of the Fund to buy, sell or otherwise transfer securities, adversely affect the trading market and price for Fund shares and cause the Fund to decline in value.

•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, sectors or companies in which the Fund invests. Common stocks are generally exposed to greater risk than other types of securities, such as preferred stocks and debt obligations, because common stockholders generally have inferior rights to receive payment from issuers.

•ETF Risks. The Fund is an ETF, and, as a result of its structure, it is exposed to the following risks:

◦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”). 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 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.

◦Costs of Buying or Selling Shares. Due to the costs of buying or selling Shares, including brokerage commissions imposed by brokers and 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.

◦Shares May Trade at Prices Other Than NAV. As with all ETFs, Shares may be bought and sold in the secondary market at market prices. Although it is expected that the market price of Shares will approximate the Fund’s NAV, there may be times when the market price of Shares is more than the NAV intra-day (premium) or less than the NAV intra-day (discount) due to supply and demand of Shares or during periods of market volatility. This risk is heightened in times of market volatility, periods of steep market declines, and periods when there is limited trading activity for Shares in the secondary market, in which case such premiums or discounts may be significant. Because securities held by the Fund may trade on foreign exchanges that are closed when the Fund’s primary listing exchange is open, the Fund is likely to experience premiums or discounts greater than those of domestic ETFs.

◦Trading. Although Shares are listed for trading on the NYSE Arca, Inc. (the “Exchange”) and may be traded on U.S. exchanges other than the Exchange, 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.

•Foreign Securities Risk. Investments in non-U.S. securities involve certain risks that may not be present with investments in U.S. securities. For example, investments in non-U.S. securities may be subject to risk of loss due to foreign currency fluctuations or to political or economic instability. Investments in non-U.S. securities also may be subject to withholding or other taxes and may be subject to additional trading, settlement, custodial, and operational risks. These and other factors can make investments in the Fund more volatile and potentially less liquid than other types of investments.

•Geographic Investment Risk. To the extent the Fund invests 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 China. The Chinese economy is generally considered an emerging market and can be significantly affected by economic and political conditions and policy in China and surrounding Asian countries. A relatively small number of Chinese companies represent a large portion of China’s total market and thus may be more sensitive to adverse political or economic circumstances and market movements. The economy of China differs, often unfavorably, from the U.S. economy in such respects as structure, general development, government involvement, wealth distribution, rate of inflation, growth rate, allocation of resources and capital reinvestment, among others. Under China’s political and economic system, the central government has historically exercised substantial control over virtually every sector of the Chinese economy through administrative regulation and/or state ownership. In addition, expropriation, including nationalization, confiscatory taxation, political, economic or social instability or other developments could adversely affect and significantly diminish the values of the Chinese companies in which the fund invests. Additionally, from time to time and as recently as January 2020, China has experienced outbreaks of infectious illnesses, and the country may be subject to other public health threats, infectious illnesses, diseases or similar issues in the future. The Fund may invest in shares of Chinese companies traded on stock markets in Mainland China or Hong Kong. These stock markets have recently experienced high levels of volatility, which may continue in the future. The Hong Kong stock market may behave differently from the Mainland China stock market and there may be little to no correlation between the performance of the Hong Kong stock market and the Mainland China stock market.

•Illiquidity Risk. Illiquidity risk exists when particular investments are difficult to purchase or sell, possibly preventing the Fund from selling these illiquid investments at an advantageous price or at the time desired. A lack of liquidity may also cause the value of investments to decline. Illiquid investments may also be difficult to value.

•Market Capitalization Risk.

◦Large-Capitalization Investing. The securities of large-capitalization companies may be relatively mature compared to smaller companies and therefore subject to slower growth during times of economic expansion. Large-capitalization companies may also be unable to respond quickly to new competitive challenges, such as changes in technology and consumer tastes.

◦Mid-Capitalization Investing. The securities of mid-capitalization companies may be more vulnerable to adverse issuer, market, political, or economic developments than securities of large-capitalization companies. The securities of mid-capitalization companies generally trade in lower volumes and are subject to greater and more unpredictable price changes than large capitalization stocks or the stock market as a whole.

◦Small-Capitalization Investing. The securities of small-capitalization companies may be more vulnerable to adverse issuer, market, political, or economic developments than securities of large- or mid-capitalization companies. The securities of small-capitalization companies generally trade in lower volumes and are subject to greater and more unpredictable price changes than large- or mid-capitalization stocks or the stock market as a whole. There is typically less publicly available information concerning smaller-capitalization companies than for larger, more established companies.

•Market Events Risk. U.S. and international markets have experienced significant periods of volatility in recent years due to a number of economic, political and global macro factors, including the impact of the coronavirus (COVID-19) pandemic and related public health issues, growth concerns in the U.S. and overseas, uncertainties regarding interest rates, trade tensions and the threat of tariffs imposed by the U.S. and other countries. These developments as well as other events could result in further market volatility and negatively affect financial asset prices, the liquidity of certain securities and the normal operations of securities exchanges and other markets. As a result, the risk environment remains elevated.

•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 lesser 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 lesser 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. However, the Fund intends to comply with the diversification requirements of the Internal Revenue Code of 1986, as amended (the “Code”) to qualify for treatment as a regulated investment company (“RIC”). For more information, please see the section entitled “Federal Income Taxes” in the SAI.

•Tracking Error Risk. As with all index funds, the performance of the Fund and its Index may differ from each other for a variety of reasons. For example, the Fund incurs operating expenses and portfolio transaction costs not incurred by the Index. In addition, the Fund may not be fully invested in the securities of the Index at all times or may hold securities not included in the Index.

Risk Lose Money [Text]

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As with any investment, there is a risk that you could lose all or a portion of your investment in the Fund.

Risk Nondiversified Status [Text]

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Because the Fund is “non-diversified,” it may invest a greater percentage of its assets in the securities of a single issuer or a lesser 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 lesser 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. However, the Fund intends to comply with the diversification requirements of the Internal Revenue Code of 1986, as amended (the “Code”) to qualify for treatment as a regulated investment company (“RIC”). For more information, please see the section entitled “Federal Income Taxes” in the SAI.

Bar Chart and Performance Table [Heading]

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Performance

Performance Narrative [Text Block]

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The following performance information indicates some of the risks of investing in the Fund. The bar chart shows the Fund’s performance for the most recent calendar year ended December 31. The table illustrates how the Fund’s average annual returns for the 1-year and since inception periods compare with those of a broad measure of market performance and the Index. The Fund’s past performance, before and after taxes, does not necessarily indicate how it will perform in the future. Updated performance information is available on the Fund’s website at www.roundhillinvestments.com.

Performance Information Illustrates Variability of Returns [Text]

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The following performance information indicates some of the risks of investing in the Fund.

Performance Availability Website Address [Text]

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www.roundhillinvestments.com

Performance Past Does Not Indicate Future [Text]

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The Fund’s past performance, before and after taxes, does not necessarily indicate how it will perform in the future.

Bar Chart [Heading]

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Calendar Year Total Return

Bar Chart Closing [Text Block]

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The calendar year-to-date total return of the Fund as of March 31, 2021 was 5.60%. During the period of time shown in the bar chart, the highest quarterly return was 48.75% for the quarter ended June 30, 2020, and the lowest quarterly return was -11.55% for the quarter ended March 31, 2020.

Year to Date Return, Label

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year-to-date total return

Bar Chart, Year to Date Return, Date

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Mar. 31, 2021

Bar Chart, Year to Date Return

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5.60%

Highest Quarterly Return, Label

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highest quarterly return

Highest Quarterly Return, Date

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Jun. 30, 2020

Highest Quarterly Return

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48.75%

Lowest Quarterly Return, Label

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lowest quarterly return

Lowest Quarterly Return, Date

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Mar. 31, 2020

Lowest Quarterly Return

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(11.55%)

Performance Table Heading

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

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

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(reflects no deduction for fees, expenses, or taxes)

Performance Table Uses Highest Federal Rate

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Performance Table Not Relevant to Tax Deferred

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Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements such as an individual retirement account (“IRA”) or other tax-advantaged accounts.

Performance Table Closing [Text Block]

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After-tax returns are calculated using the historical highest individual federal marginal income tax rates during the period covered by the table above and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their shares through tax-deferred arrangements such as an individual retirement account (“IRA”) or other tax-advantaged accounts.

Roundhill BITKRAFT Esports & Digital Entertainment ETF | Roundhill BITKRAFT Esports Index TR (reflects no deduction for fees, expenses, or taxes)

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Roundhill BITKRAFT Esports Index TR(reflects no deduction for fees, expenses, or taxes)

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91.55%

Roundhill BITKRAFT Esports & Digital Entertainment ETF | Solactive GBS Developed Markets Large & Mid Cap TR Index (reflects no deduction for fees, expenses, or taxes)

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59.23%

Inception Date

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Jun. 03, 2019

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Solactive GBS Developed Markets Large & Mid Cap TR Index(reflects no deduction for fees, expenses, or taxes)

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16.29%

Roundhill BITKRAFT Esports & Digital Entertainment ETF | Roundhill BITKRAFT Esports & Digital Entertainment ETF

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21.34%

Inception Date

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Jun. 03, 2019

Management Fees (as a percentage of Assets)

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Trading Symbol

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NERD

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0.50%

Distribution and Service (12b-1) Fees

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none

Other Expenses (as a percentage of Assets):

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none

Expenses (as a percentage of Assets)

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0.50%

Expense Example, with Redemption, 1 Year

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$ 51

Expense Example, with Redemption, 3 Years

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160

Expense Example, with Redemption, 5 Years

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280

Expense Example, with Redemption, 10 Years

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$ 628

Annual Return 2020

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89.88%

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Return Before Taxes

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89.88%

Roundhill BITKRAFT Esports & Digital Entertainment ETF | Roundhill BITKRAFT Esports & Digital Entertainment ETF | After Taxes on Distributions

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57.73%

Inception Date

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Jun. 03, 2019

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Return After Taxes on Distributions

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89.30%

Roundhill BITKRAFT Esports & Digital Entertainment ETF | Roundhill BITKRAFT Esports & Digital Entertainment ETF | After Taxes on Distributions and Sales

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57.36%

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Return After Taxes on Distributions and Sale of Shares

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53.44%

Roundhill Sports Betting & iGaming ETF

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45.16%

Objective, Primary [Text Block]

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Risk/Return [Heading]

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Roundhill Sports Betting & iGaming ETF

Objective [Heading]

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Investment Objective

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The Roundhill Sports Betting & iGaming ETF (“Sports Betting ETF” or the “Fund”) seeks to track the total return performance, before fees and expenses, of the Roundhill Sports Betting & iGaming Index (the “Index”).

Expense [Heading]

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Fees and Expenses of the Fund

Expense Narrative [Text Block]

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Shareholder Fees Caption [Text]

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Shareholder Fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

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

Portfolio Turnover [Heading]

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Portfolio Turnover

Portfolio Turnover [Text Block]

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The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Shares are held in a taxable account. These costs, which are not reflected in the Total Annual Fund Operating Expenses or in the Example, affect the Fund’s performance. For the fiscal period June 3, 2020 (commencement of operations) through December 31, 2020, the Fund’s portfolio turnover rate was 43% of the average value of its portfolio.

Portfolio Turnover, Rate

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43.00%

Expense Exchange Traded Fund Commissions [Text]

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You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and Example below.

Expense Example [Heading]

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Example

Expense Example Narrative [Text Block]

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Expense Example by, Year, Caption [Text]

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

Strategy [Heading]

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Principal Investment Strategies

Strategy Narrative [Text Block]

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The Fund uses a “passive management” (or indexing) approach to seek to track the total return performance, before fees and expenses, of the Index. The Index was developed by Roundhill Financial Inc., the Fund’s investment adviser and index provider (“Roundhill” or the “Adviser”), which tracks the performance of a tiered-weight portfolio of globally-listed equity securities of companies that are actively involved in the sports betting industry.

Roundhill Sports Betting & iGaming Index

The Index tracks the performance of the common stock (or corresponding American Depositary Receipts (“ADRs”) or Global Depositary Receipts (“GDRs”)) of exchange-listed companies that earn revenue from online gaming (“iGaming”). iGaming is broadly defined as: the wagering of money or some other value on the outcome of an event or a game, using the internet. The Index includes: (i) companies that operate in-person and/or online/internet sports books; (ii) companies that operate online/internet gambling platforms; and (iii) companies that provide infrastructure or technology to such companies. The companies in the Index are segregated into three categories by a committee comprised of staff from Roundhill (the “Committee”), specifically:

(i)“Pure-Play” Companies - iGaming companies whose primary business model and/or growth prospects are directly linked to sports betting. For these companies, continued growth in sports betting is expected to be critical to their economic success going forward.

(ii)“Core” Companies - iGaming companies with substantial operations and/or growth prospects linked to sports betting. These companies have other iGaming (non-sports betting) business units driving their economics, and thus are less affected by the growth of sports betting than pure-play companies. In time, growth in the industry and/or investments in their sports betting units may lead these companies to become pure-play companies if their sports betting operations

become a primary driver of economic performance. In most cases, the sports betting related offerings of these companies are core components of the sports betting industry.

(iii)“Non-Core” Companies - iGaming companies with some operations and/or growth prospects linked to sports betting. These companies derive the majority of their revenue from other gaming/gambling business lines not directly related to sports betting. In time, growth in the industry and/or investments in their sports betting units may lead these companies to become “core” companies if their sports betting operations become a relevant driver of economic performance. It is unlikely, based on current information, that the sports betting offerings of non-core companies would become the primary driver of such economic performance going forward.

The composition of the Index is based on the following rules:

The Index has a quarterly review in January, April, July, and October of each year, at which times the Index is reconstituted and rebalanced by Roundhill. Index components are weighted on a tiered weight basis, whereby “pure-play” companies receive 150% the initial weighting of “core” companies, which in turn receive 150% the initial weighting of “non-core” companies. These initial weights are calculated based on the number of companies under each classification in the Index upon each rebalancing, so as to ensure the total combined weight is 100%. Component changes resulting from reconstitutions are made after the market close on the third Friday in each quarterly review month and become effective at the market opening on the next trading day.

The Committee is responsible for overseeing implementation of the Index methodology. In overseeing the implementation of the methodology, the Committee will generally follow criteria for the screening, classification, and weighting process, but may adjust the inputs to or outputs from such criteria in instances in which the Committee determines that due to extenuating circumstances or unusual market conditions the results of the process do not result in an appropriate representation of a company within the Index or would be contrary to investor expectations for the Index. For example, the Committee may determine to adjust a company’s weighting in the Index in the event that the information obtained from a company’s public filing and used as part of the process to in calculate the company’s weighting in the Index was artificially inflated in the calculation period due to an extraordinary event. In addition, the Committee may determine, at a given rebalance, that a company which had previously been classified as “non-core” and thus included in the Index, has since had a material change to its overall business that justifies moving the company to "N/A" and not including the company in the Index at that time. The Committee’s goal in making these decisions is to maintain the Index’s representation of pure-play companies involved in sports betting and/or iGaming. Members of the Committee can recommend changes to the methodology and submit them to the Committee for approval.

As of March 31, 2021, the Index had 40 constituents.

The Fund’s Investment Strategy

The Fund will generally invest all, or substantially all, of its assets in the component securities that make up the Index and depositary receipts representing Index components. Under normal circumstances, at least 80% of the Fund’s net assets (plus borrowings for investment purposes) will be invested in securities issued by Sports Betting and iGaming Companies.

The Fund also may invest in securities or other investments not included in the Index, but which the Sub-Adviser believes will help the Fund track the Index. For example, the Fund may invest in securities that are not components of the Index to reflect various corporate actions and other changes to the Index (such as reconstitutions, additions, and deletions).

To the extent the Index concentrates (i.e., holds more than 25% of its total assets) in the securities of a particular industry or group of related industries, the Fund will concentrate its investments to approximately the same extent as the Index. As of March 31, 2021, the Index was concentrated in the casinos and gaming sub-industry within the consumer discretionary sector.

Risk [Heading]

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Principal Investment Risks

Risk Narrative [Text Block]

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portion of your investment in the Fund. Some or all of these risks may adversely affect the Fund’s net asset value (“NAV”), trading price, yield, total return and/or ability to meet its objective. The following risks could affect the value of your investment in the Fund:

•iGaming and Sports Betting Companies Risk. The iGaming and sports betting industry is characterized by an increasingly high degree of competition among a large number of participants including from participants performing illegal activities or unregulated companies. Expansion of iGaming and sports betting in other jurisdictions (both regulated and unregulated) could increase competition with traditional betting companies, which could have an adverse impact on their financial condition, operations and cash flows. In a broader sense, iGaming and sports betting companies face competition from all manner of leisure and entertainment activities, including shopping, athletic events, television and movies, concerts and travel. In addition, established jurisdictions could award additional licenses or permit the expansion or relocation of existing sports betting companies. These companies also may be subject to increasing regulatory constraints, particularly with respect to cybersecurity and privacy. In addition to the costs of complying with such constraints, the unintended disclosure of confidential information, whether because of an error or a cybersecurity event, could adversely affect the reputation, profitability and value of these companies.

Beginning in the first quarter of 2020, financial markets in the United States and around the world experienced extreme and in many cases unprecedented volatility and severe losses due to the global pandemic caused by COVID‑19, a novel coronavirus. The pandemic has resulted in a wide range of social and economic disruptions. Some sectors of the economy and individual issuers, including iGaming companies, have experienced particularly large losses. The shut down of all commercial sporting activity in the United States and other countries has resulted in there being no sports betting online or otherwise. The continued impact of these events or other epidemics or pandemics could have an impact on the Fund.

•Consumer Discretionary Sector Risk. Consumer discretionary companies are companies that provide non-essential goods and services, such as retailers, media companies and consumer services. These companies manufacture products and provide discretionary services directly to the consumer, and the success of these companies tied closely to the performance of the overall domestic and international economy, interest rates, competition and consumer confidence.

•ETF Risks. The Fund is an ETF, and, as a result of its structure, it is exposed to the following risks:

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.

•Market Capitalization Risk.

•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 lesser number of issuers than if it was a diversified fund. As a result, the Fund may be more exposed to the risks associated with and developments affecting an individual issuer or a lesser number of issuers than a fund that invests more widely. This may increase the Fund’s volatility and cause the performance of a relatively small number of issuers to have a greater impact on the Fund’s performance.

•Passive Investment Risk. The Fund is not actively managed and its Sub-Adviser would not sell shares of an equity security due to current or projected underperformance of a security industry or sector unless that security is removed from the Index or the selling of shares of that security is otherwise required upon a rebalancing of the Index as addressed in the Index methodology.•Tracking Error Risk. As with all index funds, the performance of the Fund and its Index may differ from each other for a variety of reasons. For example, the Fund incurs operating expenses and portfolio transaction costs not incurred by the Index. In addition, the Fund may not be fully invested in the securities of the Index at all times or may hold securities not included in the Index.

Risk Lose Money [Text]

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As with any investment, there is a risk that you could lose all or a portion of your investment in the Fund.

Risk Nondiversified Status [Text]

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Because the Fund is “non-diversified,” it may invest a greater percentage of its assets in the securities of a single issuer or a lesser number of issuers than if it was a diversified fund. As a result, the Fund may be more exposed to the risks associated with and developments affecting an individual issuer or a lesser number of issuers than a fund that invests more widely. This may increase the Fund’s volatility and cause the performance of a relatively small number of issuers to have a greater impact on the Fund’s performance.

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Performance

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Performance information for the Fund is not included because the Fund did not have a full calendar year of performance prior to the date of this Prospectus. In the future, performance information for the Fund will be presented in this section. Updated performance information is available on the Fund’s website at www.roundhillinvestments.com.

Performance One Year or Less [Text]

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Performance information for the Fund is not included because the Fund did not have a full calendar year of performance prior to the date of this Prospectus.

Performance Availability Website Address [Text]

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www.roundhillinvestments.com

Roundhill Sports Betting & iGaming ETF | Roundhill Sports Betting & iGaming ETF