Label

Element

Value

Risk/Return:

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Registrant Name

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First Trust Exchange-Traded Fund II

Prospectus Date

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Feb. 03, 2020

First Trust Indxx Global Natural Resources Income ETF

Risk/Return:

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Risk/Return [Heading]

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Summary Information

Objective [Heading]

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Investment Objective

Objective, Primary [Text Block]

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The First Trust Indxx Global Natural Resources Income ETF (the "Fund") seeks investment results that correspond generally to the price and yield (before the Fund's fees and expenses) of an equity index called the Indxx Global Natural Resources Income Index (the "Index").

Expense [Heading]

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Fees and Expenses of the Fund

Expense Narrative [Text Block]

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The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund. Investors purchasing and selling shares may be subject to costs (including customary brokerage commissions) charged by their broker, which are not reflected in the table 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 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. During the most recent fiscal year, the Fund's portfolio turnover rate was 84% of the average value of its portfolio.

Portfolio Turnover, Rate

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84.00%

Expense Example [Heading]

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Example

Expense Example, No Redemption Narrative [Text Block]

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The example below is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. This example does not take into account customary brokerage commissions that you pay when purchasing or selling shares of the Fund in the secondary market.

The example assumes that you invest $10,000 in the Fund for the time periods indicated. The example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain at current levels. 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 will normally invest at least 90% of its net assets (including investment borrowings) in the common stocks and depositary receipts that comprise the Index. The Fund, using an indexing investment approach, attempts to replicate, before fees and expenses, the performance of the Index. The Fund's investment advisor seeks a correlation of 0.95 or better (before fees and expenses) between the Fund's performance and the performance of the Index; a figure of 1.00 would represent perfect correlation. The Index is owned, developed, maintained and sponsored by Indxx, LLC (the "Index Provider"). The Index Provider reserves the right to use qualitative judgment to include, exclude, adjust, or postpone the inclusion of a stock in the Index. Continued Index membership of a constituent is not necessarily subject to the guidelines provided in the Index methodology. A security may be considered for exclusion by the Index Provider on the basis of corporate governance, accounting policies, lack of transparency and lack of representation, despite meeting all the criteria provided in the Index methodology.

The Index is a free float adjusted market capitalization weighted index designed to measure the market performance of the 50 highest dividend yielding companies involved in the upstream (i.e., generally exploration and production) segment of the natural resources sector. The term "free float" describes the portion of an issuer's outstanding securities that can be publicly traded, and therefore excludes locked-in securities held by an issuer's affiliates, officers or promoters or securities subject to some other restrictive arrangement that prevents them from being freely traded. Component securities may represent the following businesses: oil and gas exploration and production; integrated oil and gas companies; coal; steel; gold; aluminum; diversified metal and mining; industrial metals; precious metals; water; agricultural products; beverages; agricultural chemicals and fertilizers; and paper and forest products. The Index Provider's classification of an issuer and its business may be different than any other standardized industry classification applied to the issuer and may reflect only a portion of the issuer's business activities. Consequently, because an issuer's principal business activity may be outside the natural resources sector, the Fund's portfolio may include significant holdings of issuers that the Index Provider classifies in a sector that would otherwise not typically fall within the focus of the Index if classified by a different standard.

To be included in the Index, a security must be issued by a company that has (i) a positive earnings-per-share for the preceding 12 months, (ii) paid dividends in each of the prior two years and (iii) paid dividends over the preceding 12 months greater than or equal to the dividends it paid over the same 12-month period one year prior. In addition, a security must meet certain additional criteria, including that it must have a minimum free float equivalent to 10% of shares outstanding, a minimum market capitalization of $1 billion and meet certain liquidity-related requirements that focus on trading activity. Companies may generally be domiciled in any country, including emerging market countries, subject to certain exclusions determined by the Index Provider. Each eligible security is classified into five broad categories: energy, materials, agriculture, water and timber. The 50 securities with the highest dividend yield are included in the Index. The Index is then adjusted to ensure that no more than 30% of the Index's components are classified as comprising one of the five categories. Under normal market conditions, the Fund invests at least 40% of its net assets (including investment borrowings) in securities of non-U.S. issuers and invests in the securities of issuers located in at least three countries.

The Index is reconstituted annually and rebalanced quarterly and the Fund will make corresponding changes to its portfolio shortly after the Index changes are made public. The Index's quarterly rebalance schedule may cause the Fund to experience a higher rate of portfolio turnover. The Fund will be concentrated in an industry or a group of industries to the extent that the Index is so concentrated. As of December 31, 2019, the Fund had significant investments in energy companies, materials companies and European issuers, although this may change from time to time. To the extent the Fund invests a significant portion of its assets in a given jurisdiction or investment sector, the Fund may be exposed to the risks associated with that jurisdiction or investment sector.

Risk [Heading]

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Principal Risks

Risk Narrative [Text Block]

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You could lose money by investing in the Fund. An investment in the Fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. There can be no assurance that the Fund's investment objective will be achieved. The order of the below risk factors does not indicate the significance of any particular risk factor.

AGRICULTURE COMPANIES RISK. Economic forces, including forces affecting agricultural markets, as well as government policies and regulations affecting agriculture companies, could adversely impact the Fund's investments. Agricultural and livestock production and trade flows are significantly affected by government policies and regulations. Governmental policies affecting agriculture companies, such as taxes, tariffs, duties, subsidies and import and export restrictions on agricultural commodities, commodity products and livestock, can influence agriculture company profitability, the planting/raising of certain crops/livestock versus other uses of resources, the location and size of crop and livestock production, whether unprocessed or processed commodity products are traded and the volume and types of imports and exports. In addition, companies in the agriculture sector must comply with a broad range of environmental laws and regulations.

AUTHORIZED PARTICIPANT CONCENTRATION RISK. Only an authorized participant may engage in creation or redemption transactions directly with the Fund. A limited number of institutions act as authorized participants for the Fund. To the extent that these institutions exit the business or are unable to proceed with creation and/or redemption orders and no other authorized participant steps forward to create or redeem, the Fund's shares may trade at a premium or discount to the Fund's net asset value and possibly face delisting.

CURRENCY RISK. Changes in currency exchange rates affect the value of investments denominated in a foreign currency, and therefore the value of such investments in the Fund's portfolio. The Fund's net asset value could decline if a currency to which the Fund has exposure depreciates against the U.S. dollar or if there are delays or limits on repatriation of such currency. 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.

CYBER SECURITY RISK. The Fund is susceptible to operational risks through breaches in cyber security. A breach in cyber security refers to both intentional and unintentional events that may cause the Fund to lose proprietary information, suffer data corruption or lose operational capacity. Such events could cause the Fund to incur regulatory penalties, reputational damage, additional compliance costs associated with corrective measures and/or financial loss. Cyber security breaches may involve unauthorized access to the Fund's digital information systems through "hacking" or malicious software coding but may also result from outside attacks such as denial-of-service attacks through efforts to make network services unavailable to intended users. In addition, cyber security breaches of the issuers of securities in which the Fund invests or the Fund's third-party service providers, such as its administrator, transfer agent, custodian, or sub-advisor, as applicable, can also subject the Fund to many of the same risks associated with direct cyber security breaches. Although the Fund has established risk management systems designed to reduce the risks associated with cyber security, there is no guarantee that such efforts will succeed, especially because the Fund does not directly control the cyber security systems of issuers or third-party service providers.

DEPOSITARY RECEIPTS RISK. Depositary receipts may be less liquid than the underlying shares in their primary trading market. Any distributions paid to the holders of depositary receipts are usually subject to a fee charged by the depositary. Holders of depositary receipts may have limited voting rights, and investment restrictions in certain countries may adversely impact the value of depositary receipts because such restrictions may limit the ability to convert the equity shares into depositary receipts and vice versa. Such restrictions may cause the equity shares of the underlying issuer to trade at a discount or premium to the market price of the depositary receipts.

DIVIDENDS RISK. The Fund's investment in dividend-paying securities could cause the Fund to underperform similar funds that invest without consideration of an issuer's track record of paying dividends. Companies that issue dividend-paying securities are not required to continue to pay dividends on such securities. Therefore, there is the possibility that such companies could reduce or eliminate the payment of dividends in the future.

EMERGING MARKETS RISK. Investments in securities issued by companies operating in emerging market countries involve additional risks relating to political, economic, or regulatory conditions not associated with investments in securities and instruments issued by U.S. companies or by companies operating in other developed market countries. Investments in emerging markets securities are generally considered speculative in nature and are subject to the following heightened risks: smaller market capitalization of securities markets which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital; rapid inflation; and currency convertibility issues. Emerging market countries also often have less uniformity in accounting and reporting requirements, unsettled securities laws, unreliable securities valuation and greater risk associated with custody of securities. Furthermore, investors may be required to register the proceeds of sales and future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization or creation of government monopolies.

ENERGY COMPANIES RISK. The success of energy companies may be cyclical and highly dependent on energy prices. The market value of securities issued by energy companies may decline for many reasons, including, among other things, changes in the levels and volatility of global energy prices, energy supply and demand, capital expenditures on exploration and production of energy sources, exchange rates, interest rates, economic conditions, tax treatment, energy conservation efforts, increased competition and technological advances. Energy companies may be subject to substantial government regulation and contractual fixed pricing, which may increase the cost of doing business and limit the earnings of these companies. A significant portion of the revenues of energy companies may depend on a relatively small number of customers, including governmental entities and utilities. As a result, governmental budget constraints may have a material adverse effect on the stock prices of energy companies. Energy companies may also operate in, or engage in transactions involving, countries with less developed regulatory regimes or a history of expropriation, nationalization or other adverse policies. Energy companies also face a significant risk of liability from accidents resulting in injury or loss of life or property, pollution or other environmental problems, equipment malfunctions or mishandling of materials and a risk of loss from terrorism, political strife or natural disasters.

EQUITY SECURITIES RISK. The value of the Fund's shares will fluctuate with changes in the value of the equity securities in which it invests. Equity securities prices fluctuate for several reasons, including changes in investors' perceptions of the financial condition of an issuer or the general condition of the relevant equity market, such as market volatility, or when political or economic events affecting an issuer occur. Common stock prices may be particularly sensitive to rising interest rates, as the cost of capital rises and borrowing costs increase. Equity securities may decline significantly in price over short or extended periods of time, and such declines may occur in the equity market as a whole, or they may occur in only a particular country, company, industry or sector of the market.

EUROPE RISK. The Fund is subject to certain risks specifically associated with investments in the securities of European issuers. Political or economic disruptions in European countries, even in countries in which the Fund is not invested, may adversely affect security values and thus the Fund's holdings. A significant number of countries in Europe are member states in the European Union (the "EU"), and the member states no longer control their own monetary policies by directing independent interest rates for their currencies. In these member states, the authority to direct monetary policies, including money supply and official interest rates for the Euro, is exercised by the European Central Bank. In a 2016 referendum, the United Kingdom elected to withdraw from the EU ("Brexit"). After years of negotiations between the United Kingdom and the EU, a withdrawal agreement was reached that would have the United Kingdom formally leave the EU and enter a transition period during which the United Kingdom would continue to follow all EU rules and remain a member of the EU single market and customs union. During this transition period, the United Kingdom is expected to begin negotiations with the EU on a free trade agreement. Should the transition period end without the United Kingdom and the EU agreeing on such an agreement, trade and economic relations between the two parties will be governed by World Trade Organization ("WTO") rules. Under such a scenario, trade between the United Kingdom and the EU would no longer be tariff-free and non-tariff barriers such as new customs procedures would also arise, adding costs to doing business. As the second largest economy among EU members, the implications of the United Kingdom's withdrawal are difficult to gauge and cannot be fully known. Its departure may negatively impact the EU and Europe as a whole by causing volatility within the EU, triggering prolonged economic downturns in certain European countries or sparking additional member states to contemplate departing the EU (thereby perpetuating political instability in the region).

GLOBAL NATURAL RESOURCES COMPANIES RISK. Investments in global natural resources companies may be affected by numerous factors, including events occurring in nature, inflationary pressures and domestic and international politics. For example, events occurring in nature (such as earthquakes or fires in prime natural resource areas) and political events (such as coups or military confrontations) can affect the overall supply of a natural resource and the value of companies involved in such natural resource. Political risks and other risks to which non-U.S. securities are subject may also affect the U.S. companies in which the Fund invests such companies have significant operations or investments outside of the United States. In addition, interest rates, prices of raw materials and other commodities, international economic developments, energy conservation, tax and other government regulations (both U.S. and non-U.S.) may affect the supply of and demand for natural resources, which can affect the profitability and value of securities issued by global natural resources companies.

INDEX CONSTITUENT RISK. The Fund may be a constituent of one or more indices. As a result, the Fund may be included in one or more index-tracking exchange-traded funds or mutual funds. Being a component security of such a vehicle could greatly affect the trading activity involving the Fund's shares, the size of the Fund and the market volatility of the Fund. Inclusion in an index could increase demand for the Fund and removal from an index could result in outsized selling activity in a relatively short period of time. As a result, the Fund's net asset value could be negatively impacted and the Fund's market price may be below the Fund's net asset value during certain periods. In addition, index rebalances may potentially result in increased trading activity in the Fund's shares.

INDEX PROVIDER RISK. There is no assurance that the Index Provider, or any agents that act on its behalf, will compile the Index accurately, or that the Index will be determined, maintained, constructed, reconstituted, rebalanced, composed, calculated or disseminated accurately. The Index Provider and its agents do not provide any representation or warranty in relation to the quality, accuracy or completeness of data in the Index, and do not guarantee that the Index will be calculated in accordance with its stated methodology. The Advisor's mandate as described in this prospectus is to manage the Fund consistently with the Index provided by the Index Provider. The Advisor relies upon the Index provider and its agents to accurately compile, maintain, construct, reconstitute, rebalance, compose, calculate and disseminate the Index accurately. Therefore, losses or costs associated with any Index Provider or agent errors generally will be borne by the Fund and its shareholders. To correct any such error, the Index Provider or its agents may carry out an unscheduled rebalance of the Index or other modification of Index constituents or weightings. When the Fund in turn rebalances its portfolio, any transaction costs and market exposure arising from such portfolio rebalancing will be borne by the Fund and its shareholders. Unscheduled rebalances also expose the Fund to additional tracking error risk. Errors in respect of the quality, accuracy and completeness of the data used to compile the Index may occur from time to time and may not be identified and corrected by the Index Provider for a period of time or at all, particularly where the Index is less commonly used as a benchmark by funds or advisors. For example, during a period where the Index contains incorrect constituents, the Fund tracking the Index would have market exposure to such constituents and would be underexposed to the Index's other constituents. Such errors may negatively impact the Fund and its shareholders. The Index Provider and its agents rely on various sources of information to assess the criteria of issuers included in the Index, including information that may be based on assumptions and estimates. Neither the Fund nor the Advisor can offer assurances that the Index's calculation methodology or sources of information will provide an accurate assessment of included issuers.

INFLATION RISK. Inflation risk is the risk that the value of assets or income from investments will be less in the future as inflation decreases the value of money. As inflation increases, the present value of the Fund's assets and distributions may decline.

MARKET MAKER RISK. The Fund faces numerous market trading risks, including the potential lack of an active market for Fund shares due to a limited number of market markers. 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 values of the Fund's portfolio securities and the Fund's market price. The Fund may rely on a small number of third-party market makers to provide a market for the purchase and sale of shares. Any trading halt or other problem relating to the trading activity of these market makers could result in a dramatic change in the spread between the Fund's net asset value and the price at which the Fund's shares are trading on the Exchange, which could result in a decrease in value of the Fund's shares. This reduced effectiveness could result in Fund shares trading at a discount to net asset value and also in greater than normal intraday bid-ask spreads for Fund shares.

MARKET RISK. Market risk is the risk that a particular security, or shares of the Fund in general, may fall in value. Securities are subject to market fluctuations caused by such factors as economic, political, regulatory or market developments, changes in interest rates and perceived trends in securities prices. Shares of the Fund could decline in value or underperform other investments.

MATERIALS COMPANIES RISK. Materials and processing companies are involved in the extraction or processing of raw materials such as metals, ore and forestry products. These companies are sensitive to changes in the business cycle and fluctuations in the supply and demand for raw materials. Further, certain materials and processing companies can be affected by shifts in the housing market, as many produced raw materials are components of construction projects. Rising wage costs can also impact companies that rely on skilled labor. In addition, materials and processing companies may be significantly affected by volatility of commodity prices, import controls, worldwide competition, liability for environmental damage, depletion of resources and mandated expenditures for safety and pollution control devices.

NON-CORRELATION RISK. The Fund's return may not match the return of the Index for a number of reasons. The Fund incurs operating expenses not applicable to the Index, and may incur costs in buying and selling securities, especially when rebalancing the Fund's portfolio holdings to reflect changes in the composition of the Index. In addition, the Fund's portfolio holdings may not exactly replicate the securities included in the Index or the ratios between the securities included in the Index.

NON-DIVERSIFICATION RISK. The Fund is classified as "non-diversified" under the 1940 Act. As a result, the Fund is only limited as to the percentage of its assets which may be invested in the securities of any one issuer by the diversification requirements imposed by the Internal Revenue Code of 1986, as amended. The Fund may invest a relatively high percentage of its assets in a limited number of issuers. As a result, the Fund may be more susceptible to a single adverse economic or regulatory occurrence affecting one or more of these issuers, experience increased volatility and be highly invested in certain issuers.

NON-U.S. SECURITIES RISK. Non-U.S. securities are subject to higher volatility than securities of domestic issuers due to possible adverse political, social or economic developments, restrictions on foreign investment or exchange of securities, capital controls, lack of liquidity, currency exchange rates, excessive taxation, government seizure of assets, the imposition of sanctions by foreign governments, different legal or accounting standards, and less government supervision and regulation of securities exchanges in foreign countries.

PASSIVE INVESTMENT RISK. The Fund is not actively managed. The Fund invests in securities included in or representative of the Index regardless of investment merit. The Fund generally will not attempt to take defensive positions in declining markets. In the event that the Index is no longer calculated, the Index license is terminated or the identity or character of the Index is materially changed, the Fund will seek to engage a replacement index.

PORTFOLIO TURNOVER RISK. High portfolio turnover may result in the Fund paying higher levels of transaction costs and may generate greater tax liabilities for shareholders. Portfolio turnover risk may cause the Fund's performance to be less than expected.

PREMIUM/DISCOUNT RISK. The market price of the Fund's shares will generally fluctuate in accordance with changes in the Fund's net asset value as well as the relative supply of and demand for shares on the Exchange. The Fund's investment advisor cannot predict whether shares will trade below, at or above their net asset value because the shares trade on the Exchange at market prices and not at net asset value. 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, but not identical, to the same forces influencing the prices of the holdings of the Fund trading individually or in the aggregate at any point in time. However, given that shares can only be purchased and redeemed in Creation Units, and only to and from broker-dealers and large institutional investors that have entered into participation agreements (unlike shares of closed-end funds, which frequently trade at appreciable discounts from, and sometimes at premiums to, their net asset value), the Fund's investment advisor believes that large discounts or premiums to the net asset value of shares should not be sustained.

SIGNIFICANT EXPOSURE RISK. To the extent that the Fund invests a large percentage of its assets in a single asset class or the securities of issuers within the same country, state, region, industry or sector, an adverse economic, business or political development may affect the value of the Fund's investments more than if the Fund were more broadly diversified. A significant exposure makes the Fund more susceptible to any single occurrence and may subject the Fund to greater market risk than a fund that is more broadly diversified.

SMALLER COMPANIES RISK. Small and/or mid capitalization companies may be more vulnerable to adverse general market or economic developments, and their securities may be less liquid and may experience greater price volatility than larger, more established companies as a result of several factors, including limited trading volumes, fewer products or financial resources, management inexperience and less publicly available information. Accordingly, such companies are generally subject to greater market risk than larger, more established companies.

TIMBER COMPANIES RISK. Timber companies may be affected by numerous factors, including events occurring in nature and international politics. For example, the volume and value of timber that can be harvested from timberlands may be limited by natural disasters and other events such as fire, volcanic eruptions, insect infestation, disease, ice storms, wind storms, flooding, other weather conditions and other causes. In periods of poor logging conditions, timber companies may harvest less timber than expected. Timber companies are subject to many federal, state and local environmental and health and safety laws and regulations. In addition, rising interest rates and general economic conditions may affect the demand for timber products.

TRADING ISSUES RISK. Although the shares of the Fund 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. Further, secondary markets may be subject to irregular trading activity and wide bid-ask spreads (which may be especially pronounced for smaller funds). Trading in shares on the Exchange 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 the Exchange's "circuit breaker" rules. Market makers are under no obligation to make a market in the Fund's shares, and authorized participants are not obligated to submit purchase or redemption orders for Creation Units. In the event market makers cease making a market in the Fund's shares or authorized participants stop submitting purchase or redemption orders for Creation Units, Fund shares may trade at a larger premium or discount to their net asset value. There can be no assurance that the requirements of the Exchange necessary to maintain the listing of the Fund will continue to be met or will remain unchanged. The Fund may have difficulty maintaining its listing on the Exchange in the event the Fund's assets are small or the Fund does not have enough shareholders.

WATER COMPANIES RISK. Water companies can be significantly affected by the availability of water, the level of rainfall and the occurrence of other climatic and environmental events, changes in water consumption and water conservation. Water companies may also be negatively affected by changes in governmental regulation and spending, technological advances and increases in inflation, interest rates or the cost of raw materials. Water companies may be subject to liability for environmental damage, depletion of resources, conflicts with local communities over water rights and mandated expenditures for safety and pollution control.

Bar Chart and Performance Table [Heading]

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Annual Total Return

Performance Narrative [Text Block]

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The bar chart and table below illustrate the annual calendar year returns of the Fund based on net asset value as well as the average annual Fund and Index returns. The bar chart and table provide an indication of the risks of investing in the Fund by showing changes in the Fund's performance from year-to-year and by showing how the Fund's average annual total returns based on net asset value compared to those of the Index, a broad-based market index and a market index. See "Total Return Information" for additional performance information regarding the Fund. The Fund's performance information is accessible on the Fund's website at www.ftportfolios.com.

On December 18, 2015, the Fund's underlying index changed from the ISE Global Copper^TM Index to the Indxx Global Natural Resources Income Index. Therefore, the Fund's performance and historical returns shown below are not necessarily indicative of the performance that the Fund, based on the Index, would have generated. Returns for an underlying index are only disclosed for those periods in which the index was in existence for the whole period. Because the Fund's new underlying index had an inception date of June 1, 2015, it was not in existence for any of the periods disclosed.

Bar Chart [Heading]

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First Trust Indxx Global Natural Resources Income ETFCalendar Year Total Returns as of 12/31

Bar Chart Closing [Text Block]

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During the periods shown in the chart above:

Best Quarter		Worst Quarter
15.51%	December 31, 2011	-37.68%	September 30, 2011

Performance Table Heading

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Average Annual Total Returns for the Periods Ended December 31, 2019

Performance Table Narrative

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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.

Returns before taxes do not reflect the effects of any income or capital gains taxes. All after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of any state or local tax. Returns after taxes on distributions reflect the taxed return on the payment of dividends and capital gains. Returns after taxes on distributions and sale of shares assume you sold your shares at period end, and, therefore, are also adjusted for any capital gains or losses incurred. Returns for the market indices do not include expenses, which are deducted from Fund returns, or taxes.

Your own actual after-tax returns will depend on your specific tax situation and may differ from what is shown here. After-tax returns are not relevant to investors who hold Fund shares in tax-deferred accounts such as individual retirement accounts (IRAs) or employee-sponsored retirement plans.

First Trust Indxx Global Natural Resources Income ETF | First Trust Indxx Global Natural Resources Income ETF

Risk/Return:

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Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)

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none

Management Fees

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0.70%

Distribution and Service (12b-1) Fees

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none

Other Expenses

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none

Total Annual Fund Operating Expenses

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0.70%

1 Year

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$ 72

3 Years

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224

5 Years

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390

10 Years

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$ 871

2011

rr_AnnualReturn2011

(29.36%)

2012

rr_AnnualReturn2012

5.61%

2013

rr_AnnualReturn2013

(24.92%)

2014

rr_AnnualReturn2014

(16.36%)

2015

rr_AnnualReturn2015

(45.76%)

2016

rr_AnnualReturn2016

21.96%

2017

rr_AnnualReturn2017

12.53%

2018

rr_AnnualReturn2018

(9.03%)

2019

rr_AnnualReturn2019

21.57%

Highest Quarterly Return, Label

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Best Quarter

Highest Quarterly Return, Date

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Dec. 31, 2011

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

15.51%

Lowest Quarterly Return, Label

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Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

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(37.68%)

1 Year

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21.57%

5 Years

rr_AverageAnnualReturnYear05

(3.81%)

Since Inception

rr_AverageAnnualReturnSinceInception

(5.71%)

Inception Date

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Mar. 11, 2010

First Trust Indxx Global Natural Resources Income ETF | After tax on distributions | First Trust Indxx Global Natural Resources Income ETF

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

18.45%

5 Years

rr_AverageAnnualReturnYear05

(5.28%)

Since Inception

rr_AverageAnnualReturnSinceInception

(6.88%)

First Trust Indxx Global Natural Resources Income ETF | After tax on distributions and sale of fund shares | First Trust Indxx Global Natural Resources Income ETF

Risk/Return:

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1 Year

rr_AverageAnnualReturnYear01

12.67%

5 Years

rr_AverageAnnualReturnYear05

(3.51%)

Since Inception

rr_AverageAnnualReturnSinceInception

(4.38%)

First Trust Indxx Global Natural Resources Income ETF | Indxx Global Natural Resources Income Index (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

23.29%

^[1]

5 Years

rr_AverageAnnualReturnYear05

^[1]

Since Inception

rr_AverageAnnualReturnSinceInception

^[1]

First Trust Indxx Global Natural Resources Income ETF | MSCI All Country World Materials Index (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

20.12%

5 Years

rr_AverageAnnualReturnYear05

6.27%

Since Inception

rr_AverageAnnualReturnSinceInception

2.85%

First Trust Indxx Global Natural Resources Income ETF | MSCI All Country World Index (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

26.60%

5 Years

rr_AverageAnnualReturnYear05

8.41%

Since Inception

rr_AverageAnnualReturnSinceInception

8.81%

[1] On December 18, 2015, the Fund's underlying index changed from the ISE Global Copper(TM) Index to the Indxx Global Natural Resources Income Index. Since the Fund's new underlying index had an inception date of June 1, 2015, it was not in existence for all of the periods disclosed.