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SUMMARY INFORMATION

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The First Trust Dorsey Wright Focus 5 ETF (the "Fund") seeks investment results that correspond generally to the price and yield (before the Fund's fees and expenses) of an index called the Dorsey Wright Focus Five Index (the "Index").

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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.

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ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

rr_PortfolioTurnoverTextBlock

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when 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 fiscal period March 5, 2014 (inception) through September 30, 2014, the Fund's portfolio turnover rate was 0% of the average value of its portfolio.

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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, excluding acquired fund fees and expenses, remain at current levels until March 31, 2016 and thereafter at 1.19% to represent the imposition of the 12b-1 fee of 0.25% per annum of the Fund's average daily net assets. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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The Fund will normally invest at least 90% of its net assets (plus the amount of any borrowings for investment purposes) in the exchange-traded funds ("ETFs") that comprise the Index. The ETFs in which the Fund invests are advised by First Trust Advisors L.P., the Fund's investment advisor ("First Trust" or the "Advisor").

The Fund, using an indexing investment approach, attempts to replicate, before fees and expenses, the performance of the Index. First Trust 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 was developed by Dorsey, Wright & Associates (the "Index Provider"). The Index is constructed pursuant to the Index Provider's proprietary methodology, which takes into account the performance of each of the First Trust sector-based ETFs relative to one another. The Index is designed to provide targeted exposure to the five First Trust sector-based ETFs that the Index Provider believes offer the greatest potential to outperform the other ETFs in the selection universe. The Index Provider has retained The NASDAQ OMX(R) Group, Inc. ("NASDAQ OMX(R)"), to calculate and maintain the Index.

The Index Provider believes that the most adaptive tool to achieve the goal of discerning the strongest trends versus that of the weakest is relative strength. Relative strength measures the price performance of a security versus a market average, another security or a universe of securities. A security's relative strength can improve if it rises more than the market in an uptrend, or goes down less than the market in a downtrend. With respect to the Index, the Index Provider uses relative strength to evaluate the momentum of each First Trust sector-based ETF to determine the five ETFs that have the highest level of momentum, which the Index Provider considers to have the greatest probability of outperforming the other First Trust sector-based ETFs. The Index Provider selects the Index's potential inventory and uses the price data of the selected First Trust ETFs to perform relative strength analysis. When determining relative strength, the Index Provider does not perform the analysis within a finite time period, rather the Index Provider takes into account a variety of factors to track movements and trends of securities prices over various time periods. The Index Provider has constructed the Index to identify longer term trends though a series of observations, which are used to determine the inputs for the relative strength analysis.

Security selection for the Index will be conducted in the following manner:

The selection universe of the Index begins with all of the First Trust ETFs.
The Index Provider then identifies the First Trust ETFs that are designed to target a specific sector or industry group, or that have a significant overweight towards a particular sector or industry group.
The components are then ranked using a relative strength methodology that is based upon each ETF's market performance and characteristics that the Index Provider believes offer the greatest potential to outperform the other ETFs in the selection universe. Relative strength is a momentum technique that relies on unbiased, unemotional and objective data, rather than biased forecasting and subjective research. Relative strength is a way of recording historic performance patterns, and the Index Provider uses relative strength signals as a trend indicator for current momentum trends of a security versus another security.
The Index Provider then selects the five top-ranking First Trust ETFs according to the proprietary relative strength methodology for inclusion in the Index.
The Index is evaluated on a weekly basis, and the five positions within the Index are held as long as those positions continue to suggest that they will outperform the majority of the inventory of other potential First Trust ETFs on a relative basis. An Index component will only be removed if it falls to the bottom half of the universe of First Trust ETFs according to the Index Provider's proprietary relative strength methodology. An ETF is only added to the Index when a current member is removed. The Index will always be comprised of five First Trust ETFs. On the day that an addition or deletion is made to the Index, the Index is rebalanced so that the components are equally weighted. For more information regarding the Index, please refer to the "Index Information" section of the prospectus.

As of December 31, 2014, the Index was comprised of the following First Trust ETFs:

First Trust Dow Jones Internet Index Fund (FDN)
First Trust NYSE Arca Biotechnology Index Fund (FBT)
First Trust Consumer Staples AlphaDEX(R) Fund (FXG)
First Trust Consumer Discretionary AlphaDEX(R) Fund (FXD)
First Trust Health Care AlphaDEX(R) Fund (FXH)

Certain of the ETFs in which the Fund invests may invest in non-U.S. equity securities. The non-U.S. equity securities may include American depositary receipts ("ADRs"), global depositary receipts ("GDRs") or other depositary receipts.

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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.

AFFILIATED FUND RISK. The Fund invests in securities of affiliated ETFs, which involves additional expenses that would not be present in a direct investment in such affiliated ETFs. Furthermore, the Fund's investment performance and risks are directly related to the investment performance and risks of the affiliated ETFs.

BIOTECHNOLOGY/PHARMACEUTICAL COMPANIES RISK. The ETFs in which the Fund may invest are invested in biotechnology and pharmaceutical companies are subject to changing government regulation which could have a negative effect on the price, profitability and availability of their products and services. Regulations have been proposed to increase the availability and affordability of prescription drugs including proposals to increase access to generic drugs and to increase the rebates paid by drug manufacturers in exchange for Medicaid coverage of their products. Whether such proposals will be adopted cannot be predicted. In addition, such companies face increasing competition from existing generic drugs, the termination of their patent protection for certain drugs and technological advances which render their products or services obsolete. The research and development costs required to bring a drug to market are substantial and may include a lengthy review by the government, with no guarantee that the product will ever be brought to market or show a profit. In addition, the potential for an increased amount of required disclosure of proprietary scientific information could negatively impact the competitive position of these companies. Many of these companies may not offer certain drugs or products for several years, and as a result, may have significant losses of revenue and earnings.

CONSUMER DISCRETIONARY COMPANIES RISK. The ETFs in which the Fund may invest are invested in consumer discretionary companies, which manufacture products and provide discretionary services directly to the consumer, and the success of these companies is tied closely to the performance of the overall domestic and international economy, interest rates, competition and consumer confidence. Success depends heavily on disposable household income and consumer spending. Changes in demographics and consumer tastes can also affect the demand for, and success of, consumer discretionary products in the marketplace.

CONSUMER STAPLES COMPANIES RISK. The ETFs in which the Fund may invest are invested in the securities of consumer staples companies, which provide products directly to the consumer that are typically considered non-discretionary items based on consumer purchasing habits. The success of these companies is affected by a variety of factors, such as government regulations, which may affect the permissibility of using various food additives and the production methods of companies that manufacture food products.

DEPOSITARY RECEIPTS RISK. The ETFs in which the Fund invests may invest in depositary receipts, which 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.

EQUITY SECURITIES RISK. Because the Fund and the ETFs in which the Fund invests invest in equity securities, the value of the Fund's shares will fluctuate with changes in the value of these equity securities. 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 stock market, such as current market volatility, or when political or economic events affecting the issuers occur. In addition, common stock prices may be particularly sensitive to rising interest rates, as the cost of capital rises and borrowing costs increase.

ETF RISK. The Fund will invest in five First Trust sector-based ETFs. The shares of an ETF trade like common stock and represent a portfolio of securities. The risks of owning an ETF generally reflect the risks of owning the underlying securities, although lack of liquidity in an ETF could result in it being more volatile and ETFs have management fees that increase their costs.

HEALTH CARE COMPANIES RISK. The ETFs in which the Fund may invest are invested in health care companies, which are involved in medical services or health care, including biotechnology research and production, drugs and pharmaceuticals and health care facilities and services, and are subject to extensive competition, generic drug sales or the loss of patent protection, product liability litigation and increased government regulation. Research and development costs of bringing new drugs to market are substantial, and there is no guarantee that the product will ever come to market. Health care facility operators may be affected by the demand for services, efforts by government or insurers to limit rates, restriction of government financial assistance and competition from other providers.

INDEX CORRELATION RISK. You should anticipate that the value of Fund shares will decline more or less in correlation with any decline in the value of the Fund's Index.

INFORMATION TECHNOLOGY COMPANIES RISK. The ETFs in which the Fund may invest are invested in information technology companies. Information technology companies are generally subject to the risks of rapidly changing technologies, short product life cycles, fierce competition, aggressive pricing and reduced profit margins, loss of patent, copyright and trademark protections, cyclical market patterns, evolving industry standards, and frequent new product introductions. Information technology companies may be smaller and less experienced companies, with limited product lines, markets or financial resources and fewer experienced management or marketing personnel.

INTERNET COMPANIES RISK. The ETFs in which the Fund may invest are invested in the securities of Internet companies. Internet companies are subject to rapid changes in technology, worldwide competition, rapid obsolescence of products and services, loss of patent protections, cyclical market patterns, evolving industry standards and frequent new product introductions. The Fund's investment in Internet companies may also be subject to the risk of owning small capitalization companies that have recently begun operations.

MARKET RISK. Market risk is the risk that a particular ETF owned by the Fund, the underlying securities in which the ETFs invest, 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.

MOMENTUM INVESTING RISK. The Index employs a "momentum" style methodology that emphasizes selecting ETFs that have had higher recent price performance compared to other ETFs. The Fund may be subject to more risk because ETFs in which the Fund invests may be more volatile than a broad cross-section of ETFs or the returns on ETFs that have previously exhibited price momentum are less than returns on other styles of investing or the overall stock market. Momentum can turn quickly and cause significant variation from other types of investments.

NON-CORRELATION RISK. The Fund's return may not match the return of the Index for a number of reasons. For example, 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 Investment Company Act of 1940, as amended (the "1940 Act"). As a result, the Fund is only limited as to the percentage of its assets that 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 AND EMERGING MARKETS RISK. The ETFs in which the Fund invests may invest in securities of non-U.S. issuers, including U.S. dollar-denominated securities of non-U.S. issuers traded in the United States. 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 exchanges in foreign countries. These risks may be heightened for securities of companies located in, or with significant operations in, emerging market countries.

REPLICATION MANAGEMENT RISK. The Fund is exposed to additional market risk due to its policy of investing principally in the ETFs included in the Index. As a result of this policy, the ETFs held by the Fund will generally not be bought or sold in response to market fluctuations.

SMALLER COMPANIES RISK. The ETFs in which the Fund may invest are invested in small and/or mid capitalization companies. Such 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, 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.

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The Fund has not yet operated for a full calendar year and, therefore, performance information is not included in this section of the prospectus. See "Total Return Information" for performance information regarding the Fund.

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0.30%

rr_OtherExpensesOverAssets

none

rr_NetExpensesOverAssets

0.94%

rr_ExpenseExampleNoRedemptionYear03

349

rr_ExpenseExampleNoRedemptionYear10

1,417

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INVESTMENT OBJECTIVE

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FEES AND EXPENSES OF THE FUND

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SHAREHOLDER FEES (fees paid directly from your investment)

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PORTFOLIO TURNOVER

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EXAMPLE

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PRINCIPAL INVESTMENT STRATEGIES

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PRINCIPAL RISKS

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

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ANNUAL TOTAL RETURN

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none

Acquired Fund Fees and Expenses

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none

^[2]

rr_AcquiredFundFeesAndExpensesOverAssets

0.80%

rr_ExpenseExampleNoRedemptionYear01

112

rr_ExpenseExampleNoRedemptionYear05

704

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SUMMARY INFORMATION

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The First Trust NASDAQ Rising Dividend Achievers ETF (the "Fund") seeks investment results that correspond generally to the price and yield (before the fees and expenses) of the NASDAQ US Rising Dividend Achievers Index (the "Index").

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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.

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ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

rr_PortfolioTurnoverTextBlock

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when 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 fiscal period January 6, 2014 (inception) through September 30, 2014, the Fund's portfolio turnover rate was 62% of the average value of its portfolio.

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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 until January 31, 2016 and thereafter at 0.75% to represent the imposition of the 12b-1 fee of 0.25% per annum of the Fund's average daily net assets. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

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The Fund will normally invest at least 90% of its net assets (plus the amount of any borrowings for investment purposes) in securities that comprise the Index. The Index is composed of the securities of 50 companies with a history of raising their dividends and exhibit the characteristics to continue to do so in the future ("Index Securities"). The Index is designed to provide access to a diversified portfolio of small, mid and large capitalization income producing securities.

The Fund, using an indexing investment approach, attempts to replicate, before fees and expenses, the performance of the Index. First Trust Advisors L.P. ("First Trust" or the "Advisor"), 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 was developed by The NASDAQ(R) OMX Group, Inc. (the "Index Provider"). The Index Provider also calculates and maintains the Index. The Index is designed to provide access to a diversified portfolio of companies with a history of paying dividends. The Index methodology also considers each company's earnings growth and compares the level of cash held by the company with its debt profile. As of December 31, 2014, the Index was comprised of 48 equity securities traded on U.S. exchanges. The equity securities held by the Fund may include non-U.S. securities that are listed on U.S. securities exchanges in the form of American depositary receipts ("ADRs"), global depositary receipts ("GDRs") or other depositary receipts.

To be eligible for inclusion in the Index, a security must meet the following criteria:

be a member of the NASDAQ US Benchmark Index (NQUSB);
not be classified as Real Estate Investment Trust according to the Industry Classification Benchmark (ICB: 8670);
rank in top 500 by market capitalization;
have a minimum three month average daily dollar trading value of $5 million;
have paid a dividend in the trailing 12 months greater than the dividend paid in the trailing 12-month period three and five years prior;
having earnings per share in the most recent fiscal year greater than the earnings per share the three fiscal years prior;
have a cash-to-debt ratio greater than 50%; and
have a trailing 12-month payout ratio no greater than 65%.

Additional information regarding the Index, including weighting procedures, is described in this prospectus under "Index Information."

The Index Provider evaluates the Index components annually in March of each year for eligibility, using market data through the end of December. Eligible securities for the Index are identified as such using the eligibility criteria set forth in this prospectus under "Index Information." The Index is rebalanced quarterly. Rebalancing is effective as of the market close of the third Friday in March, June, September and December. The Index Provider may, from time to time, exercise reasonable discretion as it deems appropriate in order to ensure Index integrity. Ordinarily, a security will be removed from the Index at its last sale price.

The Fund intends to invest entirely in securities included in the Index; however, there may also be instances in which the Fund may be underweighted or overweighted in certain securities in the Index, not invest in certain securities included in the Index, purchase securities not in the Index that are appropriate to substitute for certain securities in the Index or utilize various combinations of the above techniques in seeking to track the Index.

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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.

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.

DIVIDEND RISK. There is no guarantee that the issuers of the Fund's portfolio securities will declare dividends in the future or that, if declared, they will either remain at current levels or increase over time.

EQUITY SECURITIES RISK. Because the Fund invests in equity securities, the value of the Shares will fluctuate with changes in the value of these equity securities. 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 stock market, such as current market volatility, or when political or economic events affecting the issuers occur. In addition, common stock prices may be particularly sensitive to rising interest rates, as the cost of capital rises and borrowing costs increase.

INDEX CORRELATION RISK. You should anticipate that the value of Fund shares will decline more or less in correlation with any decline in the value of the Fund's Index.

INFORMATION TECHNOLOGY COMPANY RISK. The Fund invests in information technology companies, which are generally subject to the following risks: rapidly changing technologies; short product life cycles; fierce competition; aggressive pricing and reduced profit margins; the loss of patent, copyright and trademark protections; cyclical market patterns; evolving industry standards; and frequent new product introductions. Information technology companies may be smaller and less experienced companies, with limited product lines, markets or financial resources and fewer experienced management or marketing personnel. Information technology company stocks, especially those which are Internet related, have experienced extreme price and volume fluctuations that are often unrelated to their operating performance.

MARKET RISK. Market risk is the risk that a particular security owned by the Fund 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. For example, 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 Investment Company Act of 1940, as amended (the "1940 Act"). As a result, the Fund is only limited as to the percentage of its assets that 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 exchanges in foreign countries.

REPLICATION MANAGEMENT RISK. The Fund is exposed to additional market risk due to its policy of investing principally in the securities included in the Index. As a result of this policy, securities held by the Fund will generally not be bought or sold in response to market fluctuations.

SMALL FUND RISK. The Fund currently has fewer assets than larger funds, and like other relatively 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.

SMALLER COMPANIES RISK. The Fund invests in small and/or mid capitalization companies. Such 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, 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.

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The Fund has not yet operated for a full calendar year and, therefore, performance information is not included in this section of the prospectus. See "Total Return Information" for performance information regarding the Fund.

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rr_ManagementFeesOverAssets

0.50%

rr_OtherExpensesOverAssets

none

rr_ExpenseExampleNoRedemptionYear01

51

rr_ExpenseExampleNoRedemptionYear05

392

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SUMMARY INFORMATION

rr_ObjectivePrimaryTextBlock

The First Trust NASDAQ Technology Dividend Index Fund (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 NASDAQ Technology Dividend Index(SM) (the "Index").

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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.

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

rr_PortfolioTurnoverTextBlock

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when 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 34% of the average value of its portfolio.

rr_ExpenseExampleByYearHeading

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 until January 31, 2016, and thereafter at 0.75% to represent the imposition of the 12b-1 fee of 0.25% per annum of the Fund's average daily net assets. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

rr_StrategyNarrativeTextBlock

The Fund will normally invest at least 90% of its net assets (plus the amount of any borrowings for investment purposes) in the common stocks and/or depositary receipts included in the Index.

The Fund, using an indexing investment approach, attempts to replicate, before fees and expenses, the performance of the Index. First Trust Advisors L.P. ("First Trust" or the "Advisor"), 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 was developed by The NASDAQ(R) OMX Group, Inc. (the "Index Provider"). The Index is calculated and maintained by the Index Provider. The Index includes up to 100 technology and telecommunications companies that pay a regular or common dividend. To be selected for the Index, a company must be classified as a technology or telecommunications company under the Industry Classification Benchmark ("ICB") and have a minimum market capitalization of $500 million. Non-U.S. securities in the Index are U.S.-listed securities of non-U.S. companies, some of which may be located in emerging markets. At each quarter, the Index is rebalanced so that the securities of the technology companies are given a collective weight of 80% and the securities of the telecommunications companies are given a collective weight of 20%.

The Index employs a modified market cap weighting methodology in which larger capitalization companies receive a larger Index weighting. The Index weighting methodology includes caps to prevent high concentrations among larger stocks. This methodology is applied to the dividend value of each Index security. The dividend value is calculated by multiplying dividends paid per share within the past 12 months by the current shares outstanding.

The Index Provider evaluates the Index components semi-annually in March and September for eligibility, based on January and July month-end data. Eligible components for the Index are identified as such using the eligibility criteria set forth in this prospectus under "Index Information." The Index is rebalanced quarterly in March, June, September and December. Rebalancing is effective as of the market close of the third Friday in March, June, September and December. As of December 31, 2014, the Index was comprised of 95 securities.

The Fund intends to invest entirely in securities included in the Index; however, there may also be instances in which the Fund may be underweighted or overweighted in certain securities in the Index, not invested in certain securities included in the Index, purchases securities not in the Index that are appropriate to substitute for certain securities in the Index or utilizes various combinations of the above techniques in seeking to track the Index.

rr_RiskNarrativeTextBlock

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.

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.

EQUITY SECURITIES RISK. Because the Fund invests in equity securities, the value of the Fund's shares will fluctuate with changes in the value of these equity securities. 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 stock market, such as current market volatility, or when political or economic events affecting the issuers occur. In addition, common stock prices may be particularly sensitive to rising interest rates, as the cost of capital rises and borrowing costs increase.

INDEX CORRELATION RISK. You should anticipate that the value of Fund shares will decline more or less in correlation with any decline in the value of the Fund's Index.

MARKET RISK. Market risk is the risk that a particular security owned by the Fund 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. For example, 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 Investment Company Act of 1940, as amended (the "1940 Act"). As a result, the Fund is only limited as to the percentage of its assets that 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 AND EMERGING MARKETS 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; security exchange rates; lack of liquidity; currency exchange rates; excessive taxation; government seizure of assets; different legal or accounting standards and less government supervision and regulation of exchanges in foreign countries. These risks may be heightened for securities of companies located in, or with significant operations in, emerging market countries.

REPLICATION MANAGEMENT RISK. The Fund is exposed to additional market risk due to its policy of investing principally in the securities included in the Index. As a result of this policy, securities held by the Fund will generally not be bought or sold in response to market fluctuations.

SMALLER COMPANIES RISK. The Fund invests in small and/or mid capitalization companies. Such 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, 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.

TECHNOLOGY COMPANIES RISK. The Fund invests in the securities of technology companies. Technology companies are subject to rapidly changing technologies, short product life cycles, fierce competition, aggressive pricing and reduced profit margins, loss of patent, copyright and trademark protections, cyclical market patterns, evolving industry standards and frequent new product introductions.

TELECOMMUNICATION COMPANIES RISK. The Fund invests in telecommunication companies, which are subject to risks, such as a market characterized by increasing competition and regulation by the Federal Communications Commission and various state regulatory authorities, the need to commit substantial capital to meet increasing competition, particularly in formulating new products and services using new technology and innovations that may make various products and services obsolete.

Bar Chart Closing [Text Block]

rr_PerformanceNarrativeTextBlock

The bar chart and table below illustrate the annual calendar year returns of the Fund based on net asset value for the past two years as well as the average annual Fund and Index returns for the one year and since inception periods ended December 31, 2014. 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 compare to those of the Index and two broad-based securities market indices. 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.

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.

rr_BarChartClosingTextBlock

During the two-year period ended December 31, 2014, the Fund's highest and lowest calendar quarter returns were 11.04% and 2.25%, respectively, for the quarters ended March 31, 2013 and June 30, 2013. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

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

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

rr_DistributionAndService12b1FeesOverAssets

none

^[3]

rr_NetExpensesOverAssets

0.50%

rr_ExpenseExampleNoRedemptionYear03

215

rr_ExpenseExampleNoRedemptionYear10

rr_AnnualReturn2014

rr_AverageAnnualReturnSinceInception

17.89%

rr_AverageAnnualReturnYear01

14.09%

rr_AverageAnnualReturnYear01

8.75%

rr_AverageAnnualReturnLabel

(reflects no deduction for fees, expenses or taxes)

rr_AverageAnnualReturnSinceInception

18.68%

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

13.69%

rr_AverageAnnualReturnLabel

(reflects no deduction for fees, expenses or taxes)

rr_AverageAnnualReturnSinceInception

18.22%

rr_RiskReturnAbstract

rr_ObjectiveHeading

INVESTMENT OBJECTIVE

rr_ExpenseHeading

FEES AND EXPENSES OF THE FUND

rr_ShareholderFeesCaption

SHAREHOLDER FEES (fees paid directly from your investment)

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

rr_ExpenseExampleHeading

EXAMPLE

rr_StrategyHeading

PRINCIPAL INVESTMENT STRATEGIES

rr_RiskHeading

PRINCIPAL RISKS

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

rr_BarChartAndPerformanceTableHeading

ANNUAL TOTAL RETURN

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

rr_DistributionAndService12b1FeesOverAssets

none

^[1]

rr_NetExpensesOverAssets

0.70%

rr_ExpenseExampleNoRedemptionYear03

273

rr_ExpenseExampleNoRedemptionYear10

1,140

rr_RiskReturnAbstract

rr_ObjectiveHeading

INVESTMENT OBJECTIVE

rr_ExpenseHeading

FEES AND EXPENSES OF THE FUND

rr_ShareholderFeesCaption

SHAREHOLDER FEES (fees paid directly from your investment)

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

rr_ExpenseExampleHeading

EXAMPLE

rr_StrategyHeading

PRINCIPAL INVESTMENT STRATEGIES

rr_RiskHeading

PRINCIPAL RISKS

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

rr_BarChartAndPerformanceTableHeading

ANNUAL TOTAL RETURN

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

rr_DistributionAndService12b1FeesOverAssets

none

^[1]

rr_NetExpensesOverAssets

0.70%

rr_ExpenseExampleNoRedemptionYear03

273

rr_ExpenseExampleNoRedemptionYear10

1,140

rr_RiskReturnAbstract

rr_ObjectiveHeading

INVESTMENT OBJECTIVE

rr_ExpenseHeading

FEES AND EXPENSES OF THE FUND

rr_ShareholderFeesCaption

SHAREHOLDER FEES (fees paid directly from your investment)

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

rr_ExpenseExampleHeading

EXAMPLE

rr_StrategyHeading

PRINCIPAL INVESTMENT STRATEGIES

rr_RiskHeading

PRINCIPAL RISKS

Performance Table Heading

rr_BarChartAndPerformanceTableHeading

ANNUAL TOTAL RETURN

Bar Chart [Heading]

rr_BarChartHeading

INTERNATIONAL MULTI-ASSET DIVERSIFIED INCOME INDEX FUND--TOTAL RETURN

rr_PerformanceTableHeading

AVERAGE ANNUAL TOTAL RETURNS FOR THE PERIODS ENDED DECEMBER 31, 2014

rr_RiskReturnAbstract

rr_ManagementFeesOverAssets

0.70%

rr_OtherExpensesOverAssets

none

rr_NetExpensesOverAssets

0.79%

rr_ExpenseExampleNoRedemptionYear03

306

rr_ExpenseExampleNoRedemptionYear10

1,248

rr_AverageAnnualReturnYear01

(0.23%)

Inception Date

rr_AverageAnnualReturnInceptionDate

Aug. 22, 2013

rr_RiskReturnAbstract

rr_AverageAnnualReturnSinceInception

0.81%

rr_RiskReturnAbstract

rr_AverageAnnualReturnSinceInception

1.51%

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

1.35%

rr_AverageAnnualReturnLabel

(reflects no deduction for fees, expenses or taxes)

rr_AverageAnnualReturnSinceInception

4.36%

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

(4.87%)

rr_RiskReturnHeading

SUMMARY INFORMATION

rr_ObjectivePrimaryTextBlock

The Multi-Asset Diversified Income Index Fund (the "Fund") seeks investment results that correspond generally to the price and yield (before the Fund's fees and expenses) of an index called the NASDAQ Multi-Asset Diversified Income Index(SM) (the "Index").

rr_ExpenseNarrativeTextBlock

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.

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

rr_PortfolioTurnoverTextBlock

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when 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 96% of the average value of its portfolio.

rr_ExpenseExampleByYearHeading

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 until January 31, 2016, and thereafter at 0.92% to represent the imposition of the 12b-1 fee of 0.25% per annum of the Fund's average daily net assets. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

rr_StrategyNarrativeTextBlock

The Fund will normally invest at least 90% of its net assets (plus the amount of any borrowings for investment purposes) in the common stocks and/or depositary receipts (20%), real estate investment trusts ("REITs") (20%), preferred securities (20%), master limited partnerships ("MLPs") (20%) and an exchange-traded fund ("ETF") (20%) that comprise the Index (each, an "Index Segment"). The percentages provided above reflect the approximate percentages of each of the Index Segments included in the Index as of each quarterly rebalance. The percentages will vary from these amounts between rebalances of the Index.

The Fund, using an indexing investment approach, attempts to replicate, before fees and expenses, the performance of the Index. First Trust Advisors L.P. ("First Trust" or the "Advisor"), 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 was developed by The NASDAQ(R) OMX Group, Inc. (the "Index Provider"). The Index Provider also calculates and maintains the Index. The Index is designed to provide access to a diversified portfolio of small, mid and large capitalization income producing securities, which are composed of domestic and international dividend-paying stocks, REITs, oil and gas or basic materials MLPs, U.S.-listed preferred securities and an ETF that invests in high yield or "junk" bonds. International securities included in the index are U.S.-listed securities of non-U.S. companies, some of which may be located in emerging markets.

The Index employs a modified market cap weighting methodology which assigns a pre-set weight to the five Index Segments at each quarterly rebalance. Each Index Segment has a set of separate and distinct eligibility rules and weighting procedures as described in this prospectus under "Index Information."

The Index Provider evaluates the Index components quarterly in March, June, September and December of each year for eligibility, using market data through the end of January, April, July and October, respectively. Eligible components for the Index are identified as such using the eligibility criteria set forth in this prospectus under "Index Information." The Index is rebalanced quarterly. Rebalancing is effective as of the market close of the third Friday in March, June, September and December. The reference dates for the data used in the rebalancing are at the close of trading on the last trading day in January, April, July and October, respectively. As of December 31, 2014, the Index was comprised of 119 securities.

The Fund intends to invest entirely in securities included in the Index; however, there may also be instances in which the Fund may be underweighted or overweighted in certain securities in the Index, not invested in certain securities included in the Index, purchases securities not in the Index that are appropriate to substitute for certain securities in the Index or utilizes various combinations of the above techniques in seeking to track the Index.

rr_RiskNarrativeTextBlock

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.

CREDIT RISK. Credit risk is the risk that an issuer of a security will be unable or unwilling to make dividend, interest and/or principal payments when due and the related risk that the value of a security may decline because of concerns about the issuer's ability to make such payments. Credit risk may be heightened if the ETF in which the Fund invests holds "high yield" or "junk" securities. Such securities, while generally offering higher yields than investment grade debt with similar maturities, involve greater risks, including the possibility of dividend or interest deferral, default or bankruptcy, and are regarded as predominantly speculative with respect to the issuer's capacity to pay dividends or interest and repay principal.

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.

EQUITY SECURITIES RISK. Because the Fund invests in equity securities, the value of the Fund's shares will fluctuate with changes in the value of these equity securities. 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 stock market, such as current market volatility, or when political or economic events affecting the issuers occur. In addition, common stock prices may be particularly sensitive to rising interest rates, as the cost of capital rises and borrowing costs increase.

ETF RISK. An ETF trades like common stock and represents a portfolio of securities. The risks of owning an ETF generally reflect the risks of owning the underlying securities, although lack of liquidity in an ETF could result in it being more volatile and ETFs have management fees that increase their costs.

FIXED INCOME SECURITIES RISK. The Fund invests in an ETF that invests in fixed income securities. Fixed income securities are subject to credit risk and interest rate risk. The ETF may invest in high yield fixed income securities, commonly referred to as "junk" bonds.

HIGH YIELD SECURITIES RISK. The ETF in which the Fund invests may invest in high yield securities, or "junk" bonds. High yield securities are subject to greater market fluctuations and risk of loss than securities with higher ratings, and therefore, may be highly speculative. These securities are issued by companies that may have limited operating history, narrowly focused operations, and/or other impediments to the timely payment of periodic interest and principal at maturity. If the economy slows down or dips into recession, the issuers of high yield securities may not have sufficient resources to continue making timely payment of periodic interest and principal at maturity. The market for high yield securities is smaller and less liquid than that for investment grade securities. High yield securities are generally not listed on a national securities exchange but trade in the over-the-counter markets. Due to the smaller, less liquid market for high yield securities, the bid-offer spread on such securities is generally greater than it is for investment grade securities and the purchase or sale of such securities may take longer to complete.

INDEX CORRELATION RISK. You should anticipate that the value of Fund shares will decline more or less in correlation with any decline in the value of the Fund's Index.

INFRASTRUCTURE COMPANIES RISK. The Fund invests in infrastructure companies and is subject to certain risks inherent in investing in these types of securities. Infrastructure companies may be directly affected by energy commodity prices, especially those infrastructure companies that own the underlying energy commodity. A decrease in the production or availability of natural gas, natural gas liquids, crude oil, coal or other energy commodities or a decrease in the volume of such commodities available for transportation, processing, storage or distribution may adversely impact the financial performance of infrastructure companies. Infrastructure companies are subject to significant federal, state and local government regulation in virtually every aspect of their operations, including how facilities are constructed, maintained and operated, environmental and safety controls, and the prices they may charge for products and services. Various governmental authorities have the power to enforce compliance with these regulations and the permits issued under them and violators are subject to administrative, civil and criminal penalties, including civil fines, injunctions or both. Stricter laws, regulations or enforcement policies could be enacted in the future which would likely increase compliance costs and may adversely affect the financial performance of infrastructure companies. Natural disasters, such as hurricanes in the Gulf of Mexico, also may impact infrastructure companies.

Certain infrastructure companies in the utilities industry are subject to the imposition of rate caps, increased competition due to deregulation, the difficulty in obtaining an adequate return on invested capital or in financing large construction projects, the limitations on operations and increased costs and delays attributable to environmental considerations, and the capital market's ability to absorb utility debt. In addition, taxes, government regulation, global politics, price and supply fluctuations, volatile interest rates and energy conservation may cause difficulties for these companies. Such issuers have been experiencing certain of these problems to varying degrees.

INTEREST RATE RISK. The Fund is subject to interest rate risk because the value of the debt securities held by the ETF, preferred securities held by the Fund, and REITs in which the Fund invests will decline with rising market interest rates. Interest rate risk is generally lower for shorter-term investments and higher for longer-term investments. Increases in interest rates typically lower the present value of a REIT's future earnings stream, and may make financing property purchases and improvements more costly. Because the market price of REIT stocks may change based upon investors' collective perceptions of future earnings, the value of the Fund will generally decline when investors anticipate or experience rising interest rates.

Rising interest rates could adversely impact the financial performance of MLPs. Rising interest rates may increase an MLP's cost of capital, which would increase operating costs and may reduce an MLP's ability to execute acquisitions or expansion projects in a cost-effective manner. Rising interest rates may also impact the price of MLP units as the yields on alternative investments increase.

MARKET RISK. Market risk is the risk that a particular security owned by the Fund 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.

MLP RISK. An investment in MLP units involves risks which differ from an investment in common stock of a corporation. Holders of MLP units have limited control and voting rights on matters affecting the partnership. In addition, there are certain tax risks associated with an investment in MLP units and conflicts of interest exist between common unit holders and the general partner, including those arising from incentive distribution payments. In addition, there is the risk that a MLP could be, contrary to its intention, taxed as a corporation, resulting in decreased returns from such MLP.

NON-CORRELATION RISK. The Fund's return may not match the return of the Index for a number of reasons. For example, 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-U.S. SECURITIES AND EMERGING MARKETS 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 exchanges in foreign countries. These risks may be heightened for securities of companies located in, or with significant operations in, emerging market countries.

PREFERRED SECURITIES RISK. Preferred securities combine some of the characteristics of both common stocks and bonds. Preferred securities are typically subordinated to bonds and other debt instruments in a company's capital structure, in terms of priority to corporate income, and therefore will be subject to greater credit risk than those debt instruments. Preferred securities are also subject to credit risk, interest rate risk and income risk.

REIT INVESTMENT RISK. Because the Fund invests in REITs, the Fund is subject to the risks associated with investing in real estate, which may include, but are not limited to, fluctuations in the value of underlying properties; defaults by borrowers or tenants; market saturation; changes in general and local operating expenses; and other economic, political or regulatory occurrences affecting companies in the real estate industry. In addition to risks related to investments in real estate generally, investing in REITs involves certain other risks related to their structure and focus, which include, but are not limited to, dependency upon management skills, limited diversification, the risks of locating and managing financing for projects, heavy cash flow dependency, possible default by borrowers, the costs and potential losses of self-liquidation of one or more holdings, the risk of a possible lack of mortgage funds and associated interest rate risks, overbuilding, property vacancies, increases in property taxes and operating expenses, changes in zoning laws, losses due to environmental damages, changes in neighborhood values and appeal to purchases, the possibility of failing to maintain exemptions from registration under the 1940 Act and, in many cases, relatively small market capitalization, which may result in less market liquidity and greater price volatility. REITs are also subject to the risk that the real estate market may experience an economic downturn generally, which may have a material effect on the real estate in which the REITs invest and their underlying portfolio securities.

REPLICATION MANAGEMENT RISK. The Fund is exposed to additional market risk due to its policy of investing principally in the securities included in the Index. As a result of this policy, securities held by the Fund will generally not be bought or sold in response to market fluctuations.

SMALLER COMPANIES RISK. The Fund invests in small and/or mid capitalization companies. Such 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, 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.

Bar Chart Closing [Text Block]

rr_PerformanceNarrativeTextBlock

The bar chart and table below illustrate the annual calendar year returns of the Fund based on net asset value for the past two years as well as the average annual Fund and Index returns for the one year and since inception periods ended December 31, 2014. 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 compare to those of the Index and two broad-based securities market indices. 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.

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.

rr_BarChartClosingTextBlock

During the two-year period ended December 31, 2014, the Fund's highest and lowest calendar quarter returns were 11.30% and -2.61%, respectively, for the quarters ended March 31, 2013 and September 30, 2014. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

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

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Acquired Fund Fees and Expenses

rr_DistributionAndService12b1FeesOverAssets

none

^[3]

rr_AcquiredFundFeesAndExpensesOverAssets

0.07%

rr_ExpenseExampleNoRedemptionYear01

68

rr_ExpenseExampleNoRedemptionYear05

rr_AnnualReturn2013

rr_AverageAnnualReturnYear01

7.91%

Inception Date

rr_AverageAnnualReturnInceptionDate

Aug. 13, 2012

rr_RiskReturnAbstract

rr_AverageAnnualReturnSinceInception

5.81%

rr_RiskReturnAbstract

rr_AverageAnnualReturnSinceInception

5.23%

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

8.88%

rr_AverageAnnualReturnLabel

(reflects no deduction for fees, expenses or taxes)

rr_AverageAnnualReturnSinceInception

19.95%

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

15.36%

rr_RiskReturnHeading

SUMMARY INFORMATION

rr_ObjectivePrimaryTextBlock

The First Trust High Income ETF's (the "Fund") primary investment objective is to provide current income. The Fund's secondary investment objective is to provide capital appreciation.

rr_ExpenseNarrativeTextBlock

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.

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

rr_PortfolioTurnoverTextBlock

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when 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 fiscal period January 6, 2014 (inception) through September 30, 2014, the Fund's portfolio turnover rate was 54% of the average value of its portfolio.

rr_ExpenseExampleByYearHeading

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 until January 31, 2016 and thereafter at 1.10% to represent the imposition of the 12b-1 fee of 0.25% per annum of the Fund's average daily net assets. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

rr_StrategyNarrativeTextBlock

The Fund will pursue its objectives by investing in large cap equity securities listed on U.S. exchanges and by utilizing an "option strategy" consisting of writing (selling) U.S. exchange-traded covered call options on the Standard & Poor's 500(R) Index (the "Index"). Under normal market conditions, the Fund invests primarily in large cap equity securities listed on U.S. exchanges. The Fund will also employ an option strategy in which it will write U.S. exchange-traded covered call options on the Index in order to seek additional cash flow in the form of premiums on the options that may be distributed to shareholders on a monthly basis. A premium is the income received by an investor who sells or writes an option contract to another party. The market value of the option strategy may be up to 20% of the Fund's overall net asset value.

The equity securities in which the Fund will invest and the options which the Fund will write will be limited to U.S. exchange-traded securities and options. The equity securities held by the Fund will be selected using a mathematical optimization process which attempts to favor higher dividend paying common stocks for the Fund's portfolio. The equity securities held by the Fund may include non-U.S. securities that are either directly listed on a U.S. securities exchange or in the form of American depositary receipts ("ADRs") and global depositary receipts ("GDRs"). The equity securities in the Fund's portfolio will be periodically rebalanced, at the discretion of the Fund's portfolio managers. Depending on market volatility, the Fund may engage in active trading, which may result in a turnover of the Fund's portfolio greater than 100% annually.

The option portion of the portfolio will generally consist of U.S. exchange-traded covered calls on the Index that are written by the Fund. In certain instances, the Fund may also write covered call spreads on the Index. In general, a covered call is an options strategy whereby an investor holds a long position in an asset and writes (sells) call options on that same asset in an attempt to generate increased income from the asset. A covered call spread is an options strategy whereby an investor holds a long position in an asset and two short calls at one strike and a long call at a higher strike price. The call options written by the Fund will typically be a laddered portfolio of one-week, one-month, two-month and three-month call options written at-the-money to slightly out-of-the-money. A call option will give the holder the right to buy the Index at a predetermined strike price from the Fund. The notional value of calls written will be generally between 25% and 75% of the overall Fund. In general, the notional value is the total value of a leveraged position's assets.

rr_RiskNarrativeTextBlock

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 objectives will be achieved.

CASH TRANSACTION RISK. The Fund may, under certain circumstances, effect a portion of creations and redemptions for cash, rather than in-kind securities, particularly for the puts and call options in which the Fund invests. As a result, an investment in the Fund may be less tax-efficient than an investment in an exchange-traded fund that effects its creations and redemption for in-kind securities. Because the Fund may effect a portion of redemptions for cash, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. A sale of shares may result in capital gains or losses, and may also result in higher brokerage costs.

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.

DERIVATIVES RISK. The Fund's use of derivatives, such as call options, can lead to losses because of adverse movements in the price or value of the underlying asset, index or rate, which may be magnified by certain features of the options. These risks are heightened when the Fund's portfolio managers use options to enhance the Fund's return or as a substitute for a position or security, rather than solely to hedge (or offset) the risk of a position or security held by the Fund. The purchase of stock index options involves the risk that the premium and transaction costs paid by the Fund in purchasing an option will be lost as a result of unanticipated movements in prices of the securities comprising the stock index on which the option is based.

The option positions employed may present additional risk. When selling a call option, the Fund will receive a premium; however, this premium may not be enough to offset a loss incurred by the Fund if the Index level at the expiration of the call option is above the strike price by an amount equal to or greater than the premium. The value of an option may be adversely affected if the market for the option becomes less liquid or smaller, and will be affected by changes in the value and dividend rates of the stock subject to the option, an increase in interest rates, a change in the actual and perceived volatility of the stock market and the common stock and the remaining time to expiration. Additionally, the value of an option does not increase or decrease at the same rate as the underlying stock(s). In fact, the Fund's use of options may reduce the Fund's ability to profit from increases in the value of the underlying stock(s).

EQUITY SECURITIES RISK. Because the Fund invests in equity securities, the value of the Fund's shares will fluctuate with changes in the value of these equity securities. 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 stock market, such as current market volatility, or when political or economic events affecting the issuers occur. In addition, common stock prices may be particularly sensitive to rising interest rates, as the cost of the capital rises and borrowing costs increase.

MANAGEMENT RISK. The Fund is subject to management risk because it is an actively managed portfolio. In managing the Fund's investment portfolio, the Fund's investment advisor will apply investment techniques and risk analyses that may not have the desired result. There can be no guarantee that the Fund will meet its investment objectives.

MARKET RISK. Market risk is the risk that a particular security owned by the Fund 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-DIVERSIFICATION RISK. The Fund is classified as "non-diversified" under the Investment Company Act of 1940, as amended (the "1940 Act"). As a result, the Fund is only limited as to the percentage of its assets that 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. The Fund holds non-U.S. securities that are either directly listed on a U.S. securities exchange or in the form of depositary receipts. 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 exchanges in foreign countries.

SMALL FUND RISK. The Fund currently has fewer assets than larger funds, and like other relatively 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. Also, during the initial invest-up period, the Fund may depart from its principal investment strategies and invest a larger amount or all of its assets in cash equivalents or it may hold cash.

rr_PerformanceNarrativeTextBlock

The Fund has not yet operated for a full calendar year and, therefore, performance information is not included in this section of the prospectus. See "Total Return Information" for performance information regarding the Fund.

rr_RiskReturnAbstract

rr_ManagementFeesOverAssets

0.85%

rr_OtherExpensesOverAssets

none

rr_ExpenseExampleNoRedemptionYear01

87

rr_ExpenseExampleNoRedemptionYear05

582

rr_RiskReturnHeading

SUMMARY INFORMATION

rr_ObjectivePrimaryTextBlock

The First Trust Low Beta Income ETF's (the "Fund") investment objective is to provide current income.

rr_ExpenseNarrativeTextBlock

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.

rr_OperatingExpensesCaption

ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)

rr_PortfolioTurnoverTextBlock

The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when 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 fiscal period January 6, 2014 (inception) through September 30, 2014, the Fund's portfolio turnover rate was 38% of the average value of its portfolio.

rr_ExpenseExampleByYearHeading

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 until January 31, 2016 and thereafter at 1.10% to represent the imposition of the 12b-1 fee of 0.25% per annum of the Fund's average daily net assets. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

rr_StrategyNarrativeTextBlock

The Fund will pursue its objective by investing in large cap equity securities listed on U.S. exchanges and by utilizing an "option strategy" consisting of buying U.S. exchange-traded put options on the Standard & Poor's 500(R) Index (the "Index") and writing (selling) U.S. exchange-traded covered call options on the Index. Under normal market conditions, the Fund invests primarily in large cap equity securities listed on U.S. exchanges. The Fund will also employ an option strategy in which it will write U.S. exchange-traded covered call options on the Index in order to seek additional cash flow in the form of premiums on the options. A premium is the income received by an investor who sells an option contract to another party. These premiums may be distributed to shareholders on a monthly basis or used to purchase U.S. exchange-traded put options on the Index that seek to provide the Fund with downside protection and which are expected to reduce the Fund's price sensitivity to declining markets. The market value of the option strategy may be up to 20% of the Fund's overall net asset value.

The equity securities in which the Fund will invest and the options which the Fund will buy and write will be limited to U.S. exchange-traded securities and options. The equity securities held by the Fund will be selected using a mathematical optimization process which attempts to favor higher dividend paying common stocks for the Fund's portfolio. The equity securities held by the Fund may include non-U.S. securities that are either directly listed on a U.S. securities exchange or in the form of American depositary receipts ("ADRs") and global depositary receipts ("GDRs"). The equity securities in the Fund's portfolio will be periodically rebalanced, at the discretion of the Fund's portfolio managers. Depending on market volatility, the Fund may engage in active trading, which may result in turnover of the Fund's portfolio greater than 100% annually.

The option portion of the portfolio will generally consist of (i) U.S. exchange-traded covered calls on the Index that are written by the Fund and (ii) U.S. exchange-traded puts on the Index that are bought by the Fund. In certain instances, the Fund may also write covered call spreads on the Index. In general, a covered call is an options strategy whereby an investor holds a long position in an asset and writes (sells) call options on that same asset in an attempt to generate increased income from the asset. A covered call spread is an options strategy whereby an investor holds a long position in an asset and two short calls at one strike and a long call at a higher strike price. The call options written by the Fund will typically be a laddered portfolio of one-week, one-month, two-month and three-month call options written at-the-money to slightly out-of-the-money. A call option will give the holder the right to buy the Index at a predetermined strike price from the Fund. The notional value of calls written will be generally between 25% and 75% of the overall Fund. In general, the notional value is the total value of a leveraged position's assets.

The put positions held by the Fund will generally average two to three months to expiration (calculated at the time of purchase) and will consist of out-of-the-money Index put options, which is an option with a strike price that is lower than the market price of the underlying asset. A put option will give the Fund the right to sell the Index at a predetermined strike price to the writer of the put. A predetermined strike price is the specific price of the underlying asset at which the Fund may sell the Index. The notional value of the put portfolio will be generally between 10% and 75% of the overall Fund.

rr_RiskNarrativeTextBlock

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.

CASH TRANSACTION RISK. The Fund may, under certain circumstances, effect a portion of creations and redemptions for cash, rather than in-kind securities, particularly for the puts and call options in which the Fund invests. As a result, an investment in the Fund may be less tax-efficient than an investment in an exchange-traded fund that effects its creations and redemption for in-kind securities. Because the Fund may effect a portion of redemptions for cash, it may be required to sell portfolio securities in order to obtain the cash needed to distribute redemption proceeds. A sale of shares may result in capital gains or losses, and may also result in higher brokerage costs.

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.

DERIVATIVES RISK. The Fund's use of derivatives, such as call and put options, can lead to losses because of adverse movements in the price or value of the underlying asset, index or rate, which may be magnified by certain features of the options. These risks are heightened when the Fund's portfolio managers use options to enhance the Fund's return or as a substitute for a position or security, rather than solely to hedge (or offset) the risk of a position or security held by the Fund. The purchase of stock index options involves the risk that the premium and transaction costs paid by the Fund in purchasing an option will be lost as a result of unanticipated movements in prices of the securities comprising the stock index on which the option is based.

The option positions employed may present additional risk. When selling a call option, the Fund will receive a premium; however, this premium may not be enough to offset a loss incurred by the Fund if the Index level at the expiration of the call option is above the strike price by an amount equal to or greater than the premium. The value of an option may be adversely affected if the market for the option becomes less liquid or smaller, and will be affected by changes in the value and dividend rates of the stock subject to the option, an increase in interest rates, a change in the actual and perceived volatility of the stock market and the common stock and the remaining time to expiration. Additionally, the value of an option does not increase or decrease at the same rate as the underlying stock(s). In fact, the Fund's use of options may reduce the Fund's ability to profit from increases in the value of the underlying stock(s).

EQUITY SECURITIES RISK. Because the Fund invests in equity securities, the value of the Fund's shares will fluctuate with changes in the value of these equity securities. 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 stock market, such as current market volatility, or when political or economic events affecting the issuers occur. In addition, common stock prices may be particularly sensitive to rising interest rates, as the cost of the capital rises and borrowing costs increase.

MANAGEMENT RISK. The Fund is subject to management risk because it is an actively managed portfolio. In managing the Fund's investment portfolio, the Fund's investment advisor will apply investment techniques and risk analyses that may not have the desired result. There can be no guarantee that the Fund will meet its investment objective.

MARKET RISK. Market risk is the risk that a particular security owned by the Fund 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-DIVERSIFICATION RISK. The Fund is classified as "non-diversified" under the Investment Company Act of 1940, as amended (the "1940 Act"). As a result, the Fund is only limited as to the percentage of its assets that 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. The Fund holds non-U.S. securities that are either directly listed on a U.S. securities exchange or in the form of depositary receipts. 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 exchanges in foreign countries.

SMALL FUND RISK. The Fund currently has fewer assets than larger funds, and like other relatively 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. Also, during the initial invest-up period, the Fund may depart from its principal investment strategies and invest a larger amount or all of its assets in cash equivalents or it may hold cash.

rr_PerformanceNarrativeTextBlock

The Fund has not yet operated for a full calendar year and, therefore, performance information is not included in this section of the prospectus. See "Total Return Information" for performance information regarding the Fund.

rr_RiskReturnAbstract

rr_ManagementFeesOverAssets

0.85%

rr_OtherExpensesOverAssets

none

rr_ExpenseExampleNoRedemptionYear01

87