Label

Element

Value

Risk/Return:

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Registrant Name

dei_EntityRegistrantName

First Trust Exchange-Traded Fund II

Prospectus Date

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Aug. 26, 2019

First Trust International Equity Opportunities ETF

Risk/Return:

rr_RiskReturnAbstract

Risk/Return [Heading]

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<p>Summary Information</p>

Objective [Heading]

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<p>Investment Objective</p>

Objective, Primary [Text Block]

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The First Trust International Equity Opportunities ETF (the "Fund"), formerly First Trust International IPO ETF, seeks investment results that correspond generally to the price and yield (before the Fund's fees and expenses) of an index called the IPOX International Index (the "Index").

Expense [Heading]

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<p>Fees and Expenses of the Fund</p>

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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<p> <b>Shareholder Fees</b> <br />(fees paid directly from your investment)</p>

Operating Expenses Caption [Text]

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<p></p><p> <b>Annual Fund Operating Expenses</b> <br />(expenses that you pay each year as a percentage of the value of your investment)</p>

Portfolio Turnover [Heading]

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<p>Portfolio Turnover</p>

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 83% of the average value of its portfolio.

Portfolio Turnover, Rate

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83.00%

Expense Example [Heading]

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<p>Example</p>

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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<p>Principal Investment Strategies</p>

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 and is developed, maintained and sponsored by IPOX^® Schuster LLC (the "Index Provider").

The Index is a market-cap weighted portfolio measuring the performance of the top 50 companies domiciled outside the United States ranked quarterly by market capitalization in the IPOX Global Composite Index (the "Base Index") and represents, on average, 25% of the total market capitalization of the Base Index, a fully market capitalization-weighted index constructed and managed to provide a broad and objective view of global aftermarket performance of initial public offerings ("IPOs") and spin-offs in all world countries (both developed and emerging market countries). A company is eligible for inclusion in the Index on the close of the 6th trading day following its IPO and is eligible to remain in the Index until the close of the 1,000th trading day. Securities issued by companies without a minimum market capitalization of $50 million on the close of the first trading day following the IPO, companies with less than 15% public float at the IPO and companies that experience abnormally large "underpricing" in their IPO are not eligible for inclusion in the Base Index.

The Index is reconstituted quarterly to reflect changes in stock market values of Base Index constituents and IPO activity during the past quarter with potential new companies entering the Index, while other companies reach 1,000 in the Index and automatically drop out. To ensure certain diversification requirements are met, the weighting of the largest Index constituents is capped at 10% at the quarterly reconstitution event. The Index may be composed of common stocks and depositary receipts generally expected to be issued by mid, large and mega capitalization companies with capitalizations between $2 billion and $80 billion.

The Index is reconstituted and rebalanced quarterly and the Fund will make corresponding changes to its portfolio shortly after the Index changes are made public. 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, 2018, the Fund had significant investments in Chinese issuers, European issuers and Asian issuers.

In certain circumstances, such as pending corporate actions, economically significant IPOs, or spin-offs, mergers or acquisitions involving Index constituents, the Index Provider may make exceptions to the initial screening rebalancing and exit process described above. In addition, subject to the terms of the license agreement that permits the Fund to use the Index, the Index Provider may have the ability to change the Index methodology, terminate the license agreement or cease compiling, calculating and publishing the Index, in each case without the consent of the Fund, the Advisor or the Fund's shareholders.

Risk [Heading]

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<p>Principal Risks</p>

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.

ASIA RISK. The Fund is subject to certain risks specifically associated with investments in the securities of Asian issuers. Many Asian economies have experienced rapid growth and industrialization, and there is no assurance that this growth rate will be maintained. Some Asian economies are highly dependent on trade, and economic conditions in other countries within and outside Asia can impact these economies. Certain of these economies may be adversely affected by trade or policy disputes with its major trade partners. There is also a high concentration of market capitalization and trading volume in a small number of issuers representing a limited number of industries, as well as a high concentration of investors and financial intermediaries. Certain Asian countries have experienced and may in the future experience expropriation and nationalization of assets, confiscatory taxation, currency manipulation, political instability, armed conflict and social instability as a result of religious, ethnic, socio-economic and/or political unrest. In particular, escalated tensions involving North Korea and any outbreak of hostilities involving North Korea could have a severe adverse effect on Asian economies. Governments of certain Asian countries have exercised, and continue to exercise, substantial influence over many aspects of the private sector. In certain cases, the government owns or controls many companies, including the largest in the country. Accordingly, government actions could have a significant effect on the issuers of the Fund's securities or on economic conditions generally.

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.

CHINA RISK. The Fund is subject to certain risks specifically associated with investments in the securities of Chinese issuers, including those issuers with securities listed on the Hong Kong Stock Exchange. China is an emerging market and demonstrates significantly higher volatility from time to time in comparison to developed markets. The central government has historically exercised substantial control over virtually every sector of the Chinese economy through administrative regulation and/or state ownership and actions of the Chinese central and local government authorities continue to have a substantial effect on economic conditions in China. Export growth continues to be a major driver of China's rapid economic growth. Reduction in spending on Chinese products and services, institution of tariffs or other trade barriers, or a downturn in any of the economies of China's key trading partners may have an adverse impact on the Chinese economy. Recent developments in relations between the U.S. and China have heightened concerns of increased tariffs and restrictions on trade between the two countries. An increase in tariffs or trade restrictions, or even the threat of such developments, could lead to a significant reduction in international trade, which could have a negative impact on China's export industry and a commensurately negative impact on the Fund.

CONCENTRATION 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 concentration makes the Fund more susceptible to any single occurrence and may subject the Fund to greater market risk than a fund that is not so concentrated.

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 securities issuers or the Fund's third-party service providers, such as its administrator, transfer agent, custodian, or sub-advisor, as applicable, or issuers in which the Fund invests, 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.

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.

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. The United Kingdom's referendum on June 23, 2016 to leave the EU (known as "Brexit") sparked depreciation in the value of the British pound, short-term declines in the stock markets and heightened risk of continued economic volatility worldwide. Although the long-term effects of Brexit are difficult to gauge and cannot be fully known, they could have wide ranging implications for the United Kingdom's economy, including: possible inflation or recession, continued depreciation of the pound, or disruption to Britain's trading arrangements with the rest of Europe. The United Kingdom is one of the EU's largest economies. 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).

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.

IPO RISK. Shares issued by companies that have recently conducted an IPO are often subject to extreme price volatility and speculative trading due to factors such as the absence of a prior public market, unseasoned trading, the small number of shares available for trading and limited information about the issuer's business model, quality of management, earnings growth potential and other criteria used to evaluate its investment prospects. Such stocks may have exhibited price appreciation in connection with the IPO that is not sustained, and it is not uncommon for stocks to decline in value in the period following the IPO. addition, the market for IPO shares can be speculative and/or inactive for extended periods of time. There is no assurance that a Fund will be able to obtain allocable portions of IPO shares. The limited number of shares available for trading in some IPOs may make it more difficult for a Fund to buy or sell significant amounts of shares without an unfavorable impact on prevailing prices. Investors in IPO shares can be affected by substantial dilution in the value of their shares, by sales of additional shares and by concentration of control in existing management and principal shareholders.

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.

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, lack of liquidity, currency exchange rates, excessive taxation, government seizure of assets, 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.

SMALL FUND RISK. The Fund currently has fewer assets than larger funds, and like other smaller funds, large inflows and outflows may impact the Fund's market exposure for limited periods of time. This impact may be positive or negative, depending on the direction of market movement during the period affected. If the Fund fails to attract a large amount of assets, shareholders of the Fund may incur higher expenses as the Fund's fixed costs would be allocated over a smaller number of shareholders.

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.

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. 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.

Bar Chart and Performance Table [Heading]

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<p>Annual Total Return</p>

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 and a broad-based 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.

Bar Chart [Heading]

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<p>First Trust International Equity Opportunities ETF<br />Calendar Year Total Returns as of 12/31 </p>

Bar Chart Closing [Text Block]

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During the periods shown in the chart above:

Best Quarter		Worst Quarter
12.09%	March 31, 2017	-15.33%	September 30, 2015

Performance Table Heading

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<p>Average Annual Total Returns for the Periods Ended December 31, 2018</p>

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 International Equity Opportunities ETF | First Trust International Equity Opportunities 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

2015

rr_AnnualReturn2015

(4.91%)

2016

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(3.36%)

2017

rr_AnnualReturn2017

39.34%

2018

rr_AnnualReturn2018

(12.30%)

Highest Quarterly Return, Label

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Best Quarter

Highest Quarterly Return, Date

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Mar. 31, 2017

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

12.09%

Lowest Quarterly Return, Label

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Worst Quarter

Lowest Quarterly Return, Date

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Sep. 30, 2015

Lowest Quarterly Return

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(15.33%)

1 Year

rr_AverageAnnualReturnYear01

(12.30%)

Since Inception

rr_AverageAnnualReturnSinceInception

1.88%

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 04, 2014

First Trust International Equity Opportunities ETF | After tax on distributions | First Trust International Equity Opportunities ETF

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

(12.85%)

Since Inception

rr_AverageAnnualReturnSinceInception

1.29%

First Trust International Equity Opportunities ETF | After tax on distributions and sale of fund shares | First Trust International Equity Opportunities ETF

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

(7.25%)

Since Inception

rr_AverageAnnualReturnSinceInception

1.17%

First Trust International Equity Opportunities ETF | IPOX International Index (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

(11.75%)

Since Inception

rr_AverageAnnualReturnSinceInception

2.61%

First Trust International Equity Opportunities ETF | MSCI World ex USA Index (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

(14.09%)

Since Inception

rr_AverageAnnualReturnSinceInception

1.17%