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

Expense Narrative [Text Block]

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The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund. Investors purchasing and selling shares may be subject to costs (including customary brokerage commissions) charged by their broker, which are not reflected in the table below.

Operating Expenses Caption [Text]

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

Portfolio Turnover [Text Block]

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The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 40% of the average value of its portfolio.

Expense Example, No Redemption Narrative [Text Block]

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

The example assumes that you invest $10,000 in the Fund for the time periods indicated. The example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain at current levels until January 31, 2017, and thereafter at 0.95% 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:

Strategy Narrative [Text Block]

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The Fund will normally invest at least 90% of its net assets (including investment borrowings) in common stocks and/or depositary receipts that comprise the Index. The Fund, using an indexing investment approach, attempts to replicate, before fees and expenses, the performance of the Index. The Fund's investment advisor seeks a correlation of 0.95 or better (before fees and expenses) between the Fund's performance and the performance of the Index; a figure of 1.00 would represent perfect correlation. The Index is owned and is developed, maintained and sponsored by Indxx, LLC ("Indxx" or the "Index Provider").

The Index is a market capitalization weighted index designed to measure the performance of companies that are directly or indirectly engaged in improving agricultural yields. The Index is comprised of farmland companies and firms involved in chemicals and fertilizers, seeds, irrigation equipment, and farm machinery. To be included in the Index, a security must meet certain additional criteria, including that it must have a minimum market capitalization of $1 billion and meet certain liquidity-related requirements that focus on trading activity. Companies may generally be domiciled in any country, including emerging markets, subject to certain exclusions determined by the Index Provider that are based on certain criteria relating to, among other factors, liquidity. Under normal market conditions, the Fund invests at least 40% of its net assets (including investment borrowings) in securities of non-U.S. issuers and invests in the securities of issuers located in at least three countries.

The Index is reconstituted annually in March. The Index is rebalanced quarterly in June, September, December and March. For more information regarding the Index, please refer to the "Index Information" section of this prospectus. As of December 31, 2015, there were 45 securities that comprised the Index.

The Fund intends to invest in each security in the Index. The Fund also 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, may 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.

Risk Narrative [Text Block]

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

AGRICULTURE COMPANIES RISK. Companies involved in the agriculture business and farming-related activities may be affected by certain legislative or regulatory developments related to food safety, the environment, taxes and other governmental policies. Companies involved in the agriculture business and farming-related activities may face the risk of liability for environmental damage, depletion of resources, and mandated expenditures for safety and pollution control devices. An increased competitive landscape, caused by increased availability of food and other agricultural commodities, economic recession or labor difficulties, may lead to a decrease in demand for the products and services provided by companies involved in agriculture and farming-related activities.

CURRENCY RISK. The Fund may hold investments that are denominated in non-U.S. currencies, or in securities that provide exposure to such currencies, currency exchange rates or interest rates denominated in such currencies. Changes in currency exchange rates and the relative value of non-U.S. currencies will affect the value of the Fund's investment and the value of Fund shares. Currency exchange rates can be very volatile and can change quickly and unpredictably. As a result, the value of an investment in the Fund may change quickly and without warning and you may lose money.

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 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.

GERMANY INVESTMENT RISK. To the extent the Fund invests in securities of German companies, it will be subject to certain risks, including, but not limited to: significant demographic challenges to sustained long-term growth; low fertility rates and declining net immigration putting pressure on the country's social welfare system; and the costly and time-consuming modernization and integration of the eastern German economy. Additionally, the European sovereign-debt crisis has resulted in a weakened Euro and has put into question the future financial prospects of Germany and the surrounding region.

INDUSTRIALS COMPANIES RISK. Industrials companies convert unfinished goods into finished durables used to manufacture other goods or provide services. General risks of industrials companies include the general state of the economy, intense competition, consolidation, domestic and international politics, excess capacity and consumer demand and spending trends. In addition, they may also be significantly affected by overall capital spending levels, economic cycles, technical obsolescence, delays in modernization, labor relations, government regulations and e-commerce initiatives.

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.

MATERIALS COMPANIES RISK. General risks of the materials sector include the general state of the economy, consolidation, domestic and international politics and excess capacity. In addition, basic materials companies may also be significantly affected by volatility of commodity prices, import controls, worldwide competition, liability for environmental damage, depletion of resources and mandated expenditures for safety and pollution control devices.

NON-CORRELATION RISK. The Fund's return may not match the return of the Index for a number of reasons. 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; 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.

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.

SMALLER COMPANIES RISK. Small and/or mid capitalization companies may be more vulnerable to adverse general market or economic developments, and their securities may be less liquid and may experience greater price volatility than larger, more established companies as a result of several factors, including limited trading volumes, 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.

Performance Narrative [Text Block]

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The bar chart and table below illustrate the annual calendar year returns of the Fund based on net asset value as well as the average annual Fund and Index returns. The bar chart and table provide an indication of the risks of investing in the Fund by showing changes in the Fund's performance from year-to-year and by showing how the Fund's average annual total returns based on net asset value compare to those of the Index, a broad-based market index and a specialized market index. On December 18, 2015, the Fund's underlying index changed from the ISE Global Platinum(TM) Index to the Indxx Global Agriculture Index. Therefore, the Fund's performance and historical returns shown below are not necessarily indicative of the performance that the Fund, based on the Index, would have generated. Returns for an underlying index are only disclosed for those periods in which the index was in existence for the whole period. Because the Fund's new underlying index had an inception date of June 1, 2015, it was not in existence for any of the periods disclosed. 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.

Bar Chart Closing [Text Block]

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During the period shown in the chart above:

BEST QUARTER	WORST QUARTER
17.11% (September 30, 2013)	-34.63% (September 30, 2015)

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

Performance Table Footnotes

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*

On December 18, 2015, the Fund's underlying index changed from the ISE Global Platinum(TM) Index to the Indxx Global Agriculture Index. Because the Fund's new underlying index had an inception date of June 1, 2015, performance information is not included above.

Risk Return Abstract

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Management Fees

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0.70%

Other Expenses

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none

^[2]

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

$ 72

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

501

Annual Return 2011

rr_AnnualReturn2011

(47.63%)

Annual Return 2013

rr_AnnualReturn2013

(13.89%)

Annual Return 2015

rr_AnnualReturn2015

(56.15%)

5 Years

rr_AverageAnnualReturnYear05

(33.36%)

Inception Date

rr_AverageAnnualReturnInceptionDate

Mar. 11, 2010

Risk Return Abstract

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5 Years

rr_AverageAnnualReturnYear05

(33.75%)

1 Year

rr_AverageAnnualReturnYear01

(31.76%)

Since Inception

rr_AverageAnnualReturnSinceInception

(16.27%)

Risk Return Abstract

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1 Year

rr_AverageAnnualReturnYear01

Since Inception

rr_AverageAnnualReturnSinceInception

Risk Return Abstract

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

(2.36%)

Since Inception

rr_AverageAnnualReturnSinceInception

7.15%

Risk Return Abstract

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

(16.16%)

Since Inception

rr_AverageAnnualReturnSinceInception

(3.46%)

Risk Return Abstract

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Objective [Heading]

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INVESTMENT OBJECTIVE

Expense [Heading]

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FEES AND EXPENSES OF THE FUND

Shareholder Fees Caption [Text]

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SHAREHOLDER FEES (fees paid directly from your investment)

Portfolio Turnover [Heading]

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PORTFOLIO TURNOVER

Expense Example [Heading]

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EXAMPLE

Strategy [Heading]

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PRINCIPAL INVESTMENT STRATEGIES

Risk [Heading]

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PRINCIPAL RISKS

Bar Chart and Performance Table [Heading]

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ANNUAL TOTAL RETURN

Bar Chart [Heading]

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FIRST TRUST INDXX GLOBAL NATURAL RESOURCES INCOME ETF--TOTAL RETURNS

Performance Table Heading

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AVERAGE ANNUAL TOTAL RETURNS FOR THE PERIODS ENDED DECEMBER 31, 2015

Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of Offering Price)

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none

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

^[1]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.70%

3 Years

rr_ExpenseExampleNoRedemptionYear03

278

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,144

Annual Return 2012

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5.61%

Annual Return 2014

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(16.36%)

1 Year

rr_AverageAnnualReturnYear01

(45.76%)

Since Inception

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(15.72%)

1 Year

rr_AverageAnnualReturnYear01

(46.03%)

Since Inception

rr_AverageAnnualReturnSinceInception

(16.47%)

Risk Return Abstract

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5 Years

rr_AverageAnnualReturnYear05

(15.40%)

Label

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(reflects no deduction for fees, expenses or taxes)

5 Years

rr_AverageAnnualReturnYear05

Label

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(reflects no deduction for fees, expenses or taxes)

5 Years

rr_AverageAnnualReturnYear05

(7.66%)

Label

rr_AverageAnnualReturnLabel

(reflects no deduction for fees, expenses or taxes)

5 Years

rr_AverageAnnualReturnYear05

6.09%

Risk/Return [Heading]

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SUMMARY INFORMATION

Objective, Primary [Text Block]

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The First Trust International IPO 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 IPOX International Index (the "Index").

Expense Narrative [Text Block]

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The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund. Investors purchasing and selling shares may be subject to costs (including customary brokerage commissions) charged by their broker, which are not reflected in the table below.

Operating Expenses Caption [Text]

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

Portfolio Turnover [Text Block]

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The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the fiscal period November 4, 2014 (inception) through September 30, 2015, the Fund's portfolio turnover rate was 98% of the average value of its portfolio.

Expense Example, No Redemption Narrative [Text Block]

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

The example assumes that you invest $10,000 in the Fund for the time periods indicated. The example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain at current levels until January 31, 2017, and thereafter at 0.95% 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:

Strategy Narrative [Text Block]

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The Fund will normally invest at least 90% of its net assets (including investment borrowings) in common stocks and/or depositary receipts that comprise the Index. The Fund, using an indexing investment approach, attempts to replicate, before fees and expenses, the performance of the Index. The Fund's investment advisor seeks a correlation of 0.95 or better (before fees and expenses) between the Fund's performance and the performance of the Index; a figure of 1.00 would represent perfect correlation.

The Index is owned and is developed, maintained and sponsored by IPOX(R) Schuster LLC (the "Index Provider"). The Index is a market-cap weighted portfolio measuring the performance of the top 50 non-U.S. companies, including companies domiciled in emerging markets, ranked quarterly by market capitalization in the IPOX(R) Global Composite Index (the "Base Index"). The Index includes the 50 largest and typically most liquid initial public offerings ("IPOs") and spin-offs of companies legally domiciled outside the United States that trade on an accessible global stock exchange. An IPO is a public offering in which the shares of stock in a company are sold to the general public for the first time on an exchange. On a quarterly basis, each stock in the Fund's portfolio is capped at 10% of the Fund's net assets. Additionally, at each quarterly rebalance, stocks whose weights exceed 5% of the Fund's net assets will not, in the aggregate, comprise more than 50% of the Fund's net assets. The Index Provider periodically calculates a constituent equity turnover to determine each constituent's eligibility for the Index based on its liquidity.

The Index methodology starts with the Base Index, a rules-based index that measures the global performance of IPOs and spin-offs. The applicable stocks in the Base Index are ranked by total market capitalization, which is the total number of shares outstanding times closing price. Generally, the Index is comprised of mid-, large- and mega-capitalization companies. Although market capitalization ranges are constantly fluctuating, the Index Provider generally considers mid- to large/mega-capitalization to be approximately $2 billion to $80 billion. The inception date of the Index was July 25, 2014. In general, eligible constituents are added to the Base Index on the sixth day of trading and remain eligible to be included in the Base Index for approximately four years. Because a component is generally eligible for the Index after six days of public trading, the Fund may not have access to the gains derived from the initial run-up in the IPO's price. The Fund may invest in the components of the Index through depository receipts, such as American Depository Receipts ("ADRs") or Global Depository Receipts ("GDRs"). The Fund initially anticipates having significant investments in financial companies and will be concentrated in a sector or industry to the extent that the Index is so concentrated. Due to the nature of the Index's methodology, the Fund anticipates experiencing relatively high turnover. As of September 30, 2015, the Index had significant investments in financial and consumer discretionary companies.

Risk Narrative [Text Block]

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

CHINA AND HONG KONG INVESTMENT RISK. The Fund may invest in H shares, depositary receipts and U.S.-listed common stock of companies that are domiciled in China, including Hong Kong. Some Chinese companies are listed on both the Hong Kong Stock Exchange with H shares and the Shanghai Stock Exchange with A shares. Price differentials between H shares and A shares of the same company may be significant. Also, price fluctuations of A shares are limited to either 5% or 10% per trading day, while no such limitations exist for H shares. Investing in securities of companies in China involves additional risks, including, but not limited to: the economy of China differs, often unfavorably, from the economy in such respects as structure, general development, government involvement, wealth distribution, rate of inflation, growth rate, allocation of resources and capital reinvestment; the central government has historically exercised substantial control over virtually every sector of the Chinese economy through administrative regulation and/or state ownership; and actions of the Chinese central and local government authorities continue to have a substantial effect on economic conditions in China. Furthermore, China's economy is dependent on the economies of other Asian countries and can be significantly affected by currency fluctuations and increasing competition from Asia's other emerging economies. The Fund is also subject to certain risks associated specifically with Hong Kong, including Hong Kong's political and economic environment and the volatility of and the concentration of real estate companies listed on the Hong Kong Stock Exchange. Because of Hong Kong's reversion to China, any increase in uncertainty as to the economic and political status of Hong Kong, or a deterioration of the relationship between China and the United States, could have negative implications on stocks listed on the Hong Kong Stock Exchange. Securities prices on the Hong Kong Stock Exchange can be highly volatile and are sensitive to developments in Hong Kong and China, as well as other world markets.

CONSUMER DISCRETIONARY COMPANIES RISK. Consumer discretionary companies are companies that provide non-essential goods and services, such as retailers, media companies and consumer services. These companies manufacture products and provide discretionary services directly to the consumer, and the success of these companies 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.

CURRENCY RISK. The Fund may hold investments that are denominated in non-U.S. currencies, or in securities that provide exposure to such currencies, currency exchange rates or interest rates denominated in such currencies. Changes in currency exchange rates and the relative value of non-U.S. currencies will affect the value of the Fund's investment and the value of Fund shares. Currency exchange rates can be very volatile and can change quickly and unpredictably. As a result, the value of an investment in the Fund may change quickly and without warning, and you may lose money.

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. 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 the 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.

EUROPE RISK. Investments in a single region, even though representing a number of different countries within the region, may be affected by common economic forces and other factors. The Fund is subject to greater risks of adverse events which occur in the European region and may experience greater volatility than a fund that is more broadly diversified geographically. Political or economic disruptions in European countries, even in countries in which the Fund is not invested, may adversely affect security values and thus the Fund's holdings. A significant number of countries in Europe are member states in the European Union (the "EU"), and the member states no longer control their own monetary policies by directing independent interest rates for their currencies. In these member states, the authority to direct monetary policies, including money supply and official interest rates for the Euro, is exercised by the European Central Bank. Furthermore, the European sovereign debt crisis has had, and continues to have, a significant negative impact on the economies of certain European countries and their future economic outlooks.

FINANCIAL COMPANIES RISK. Financial companies are especially subject to the adverse effects of economic recession, currency exchange rates, government regulation, decreases in the availability of capital, volatile interest rates, portfolio concentrations in geographic markets and in commercial and residential real estate loans, and competition from new entrants in their fields of business.

IPO RISK. The Fund invests in companies that have recently conducted an initial public offering. The stocks of such companies are often subject to extreme price volatility and speculative trading. These stocks may have exhibited above-average price appreciation in connection with the initial public offering prior to inclusion in the Index. The price of stocks included in the Index may not continue to appreciate and the performance of these stocks may not replicate the performance exhibited in the past.

MARKET RISK. Market risk is the risk that the underlying securities in which the Fund invests, 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. Overall securities values could decline generally or could 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 "Code"). 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 concentrated 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; 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.

PORTFOLIO TURNOVER RISK. The Fund's investment strategy tracking the Index may frequently involve buying and selling portfolio securities. High portfolio turnover may result in the Fund paying higher levels of transaction costs and generating greater tax liabilities for shareholders. Portfolio turnover risk may cause the Fund's performance to be less than you expect.

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, the 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 new 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. Small and/or mid-capitalization companies may be more vulnerable to adverse general market or economic developments, and their securities may be less liquid and may experience greater price volatility than larger, more established companies as a result of several factors, including limited trading volumes, 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.

Performance Narrative [Text Block]

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

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.

Bar Chart Closing [Text Block]

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During the period shown in the chart above:

BEST QUARTER	WORST QUARTER
7.33% (December 31, 2015)	-15.33% (September 30, 2015)

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

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

^[1]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.70%

3 Years

rr_ExpenseExampleNoRedemptionYear03

278

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,144

1 Year

rr_AverageAnnualReturnYear01

(4.91%)

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 04, 2014

Risk Return Abstract

rr_RiskReturnAbstract

Since Inception

rr_AverageAnnualReturnSinceInception

(7.85%)

Risk Return Abstract

rr_RiskReturnAbstract

Since Inception

rr_AverageAnnualReturnSinceInception

(5.82%)

Risk Return Abstract

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

(4.69%)

Label

rr_AverageAnnualReturnLabel

(reflects no deduction for fees, expenses or taxes)

Since Inception

rr_AverageAnnualReturnSinceInception

(3.70%)

Risk Return Abstract

rr_RiskReturnAbstract

Objective [Heading]

rr_ObjectiveHeading

INVESTMENT OBJECTIVE

Expense [Heading]

rr_ExpenseHeading

FEES AND EXPENSES OF THE FUND

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

SHAREHOLDER FEES (fees paid directly from your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

PORTFOLIO TURNOVER

Expense Example [Heading]

rr_ExpenseExampleHeading

EXAMPLE

Strategy [Heading]

rr_StrategyHeading

PRINCIPAL INVESTMENT STRATEGIES

Risk [Heading]

rr_RiskHeading

PRINCIPAL RISKS

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

ANNUAL TOTAL RETURN

Bar Chart [Heading]

rr_BarChartHeading

FIRST TRUST ISE CLOUD COMPUTING INDEX FUND--TOTAL RETURNS

Performance Table Heading

rr_PerformanceTableHeading

AVERAGE ANNUAL TOTAL RETURNS FOR THE PERIODS ENDED DECEMBER 31, 2015

Risk Return Abstract

rr_RiskReturnAbstract

Management Fees

rr_ManagementFeesOverAssets

0.60%

Other Expenses

rr_OtherExpensesOverAssets

none

^[2]

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

$ 61

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

447

Annual Return 2012

rr_AnnualReturn2012

15.53%

Annual Return 2014

rr_AnnualReturn2014

7.42%

1 Year

rr_AverageAnnualReturnYear01

5.89%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 05, 2011

Risk Return Abstract

rr_RiskReturnAbstract

Since Inception

rr_AverageAnnualReturnSinceInception

9.33%

Risk Return Abstract

rr_RiskReturnAbstract

Since Inception

rr_AverageAnnualReturnSinceInception

7.38%

Risk Return Abstract

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

6.63%

Label

rr_AverageAnnualReturnLabel

(reflects no deduction for fees, expenses or taxes)

Since Inception

rr_AverageAnnualReturnSinceInception

12.29%

Risk Return Abstract

rr_RiskReturnAbstract

1 Year

rr_AverageAnnualReturnYear01

5.60%

Risk/Return [Heading]

rr_RiskReturnHeading

SUMMARY INFORMATION

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The First Trust ISE Global Engineering and Construction 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 ISE Global Engineering and Construction(TM) Index (the "Index").

Expense Narrative [Text Block]

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.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

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

Portfolio Turnover [Text Block]

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 Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 46% of the average value of its portfolio.

Expense Example, No Redemption Narrative [Text Block]

rr_ExpenseExampleNoRedemptionNarrativeTextBlock

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, 2017, and thereafter at 1.24% to represent the imposition of the 12b-1 fee of 0.25% per annum of the Fund's average daily net assets. The example assumes that First Trust's agreement to waive fees and/or pay the Fund's expenses to the extent necessary to prevent the operating expenses of the Fund (excluding interest expense, brokerage commissions and other trading expenses, taxes, and extraordinary expenses) from exceeding 0.70% of average daily net assets per year will be terminated following January 31, 2017. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The Fund will normally invest at least 90% of its net assets (including investment borrowings) in common stocks or in depositary receipts representing securities in the Index. The Fund's investment advisor seeks to match the performance of the Index (before the Fund's fees and expenses).

The Fund, using an indexing investment approach, attempts to replicate, before fees and expenses, the performance of the Index. The Fund's investment advisor seeks a correlation of 0.95 or better (before fees and expenses) between the Fund's performance and the performance of the Index; a figure of 1.00 would represent perfect correlation.

The Index is owned and was developed by the International Securities Exchange, LLC(R) ("ISE" or "Index Provider"). The Index Provider has contracted with Standard & Poor's Dow Jones Indices to calculate and maintain the Index. The Index provides a benchmark for investors interested in tracking public companies throughout the world that are active in the engineering and construction industries, based on analysis of the products and services offered by those companies. The Index specifically targets companies that are engaged in large civil and capital projects such as infrastructure, utilities, transportation, telecommunications, commercial, residential, and commerce facilities and whose roles are within the engineering, designing, planning, consulting, project managing, and/or constructing of these projects. To be included in the Index, a company must receive at least 70% of revenues from these types of services and projects based on the reportable segment/division from its most recent annual report. As of September 30, 2015, the Index had significant investments in industrials companies.

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.

Risk Narrative [Text Block]

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.

CURRENCY RISK. The Fund may hold investments that are denominated in non-U.S. currencies, or in securities that provide exposure to such currencies, currency exchange rates or interest rates denominated in such currencies. Changes in currency exchange rates and the relative value of non-U.S. currencies will affect the value of the Fund's investment and the value of Fund shares. Currency exchange rates can be very volatile and can change quickly and unpredictably. As a result, the value of an investment in the Fund may change quickly and without warning and you may lose money.

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.

ENGINEERING AND CONSTRUCTION COMPANIES RISK. Risks associated with investing in engineering and construction companies include the general state of the economy, demand for their specific products or services, changes in government spending, zoning laws, interest rates, declines in real estate values, environmental damage and product liability claims. In addition, they may also be significantly affected by overall capital spending levels, economic cycles, technical obsolescence, delays in modernization, labor relations, government regulations and e-commerce initiatives.

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 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.

INDUSTRIALS COMPANIES RISK. Industrials companies convert unfinished goods into finished durables used to manufacture other goods or provide services. Some industrials companies are involved in electrical equipment and components, industrial products, manufactured housing and telecommunications equipment. General risks of industrials companies include the general state of the economy, intense competition, consolidation, domestic and international politics, excess capacity and consumer demand and spending trends. In addition, they may also be significantly affected by overall capital spending levels, economic cycles, technical obsolescence, delays in modernization, labor relations, government regulations and e-commerce initiatives.

JAPAN RISK. Because Japan's economy and equity market share a strong correlation with the U.S. markets, the Japanese economy may be affected by economic problems in the U.S. Japan also has a growing economic relationship with China and other Southeast Asian countries, and thus Japan's economy may also be affected by economic, political or social instability in those countries. Despite a strengthening in the economic relationship between Japan and China, the countries' political relationship has at times been strained in recent years. Should political tension increase, it could adversely affect the economy and destabilize the region as a whole. Japan also remains heavily dependent on oil imports, and higher commodity prices could therefore have a negative impact on the economy. Japanese securities may also be subject to lack of liquidity; excessive taxation; government seizure of assets; different legal or accounting standards and less government supervision and regulation of exchanges than in the United States. Furthermore, the natural disasters that have impacted Japan and the ongoing recovery efforts have had a negative affect on Japan's economy, and may continue to do so.

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-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. 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.

SMALLER COMPANIES RISK. Small and/or mid capitalization companies may be more vulnerable to adverse general market or economic developments, and their securities may be less liquid and may experience greater price volatility than larger, more established companies as a result of several factors, including limited trading volumes, 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.

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

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

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.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the period shown in the chart above:

BEST QUARTER	WORST QUARTER
28.36% (June 30, 2009)	-24.67% (September 30, 2011)

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

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

^[1]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.99%

Total Net Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursement

rr_NetExpensesOverAssets

0.70%

3 Years

rr_ExpenseExampleNoRedemptionYear03

340

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,452

Annual Return 2010

rr_AnnualReturn2010

18.23%

Annual Return 2012

rr_AnnualReturn2012

19.21%

Annual Return 2014

rr_AnnualReturn2014

(10.66%)

1 Year

rr_AverageAnnualReturnYear01

(0.59%)

Since Inception

rr_AverageAnnualReturnSinceInception

7.13%

1 Year

rr_AverageAnnualReturnYear01

(1.06%)

Since Inception

rr_AverageAnnualReturnSinceInception

6.51%

Risk Return Abstract

rr_RiskReturnAbstract

5 Years

rr_AverageAnnualReturnYear05

0.86%

Label

rr_AverageAnnualReturnLabel

(reflects no deduction for fees, expenses or taxes)

5 Years

rr_AverageAnnualReturnYear05

2.76%

Label

rr_AverageAnnualReturnLabel

(reflects no deduction for fees, expenses or taxes)

5 Years

rr_AverageAnnualReturnYear05

12.18%

Label

rr_AverageAnnualReturnLabel

(reflects no deduction for fees, expenses or taxes)

5 Years

rr_AverageAnnualReturnYear05

6.71%

Risk/Return [Heading]

rr_RiskReturnHeading

SUMMARY INFORMATION

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The First Trust ISE Global Wind Energy 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 ISE Global Wind Energy(TM) Index (the "Index").

Expense Narrative [Text Block]

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.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

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

Portfolio Turnover [Text Block]

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 Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 25% of the average value of its portfolio.

Expense Example, No Redemption Narrative [Text Block]

rr_ExpenseExampleNoRedemptionNarrativeTextBlock

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, 2017, and thereafter at 1.00% to represent the imposition of the 12b-1 fee of 0.25% per annum of the Fund's average daily net assets. The example assumes that First Trust's agreement to waive fees and/or pay the Fund's expenses to the extent necessary to prevent the operating expenses of the Fund (excluding interest expense, brokerage commissions and other trading expenses, taxes, and extraordinary expenses) from exceeding 0.60% of average daily net assets per year will be terminated following January 31, 2017. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The Fund will normally invest at least 90% of its net assets (including investment borrowings) in common stocks or in depositary receipts representing securities in the Index. The Fund's investment advisor seeks to match the performance of the Index (before the Fund's fees and expenses).

The Fund, using an indexing investment approach, attempts to replicate, before fees and expenses, the performance of the Index. The Fund's investment advisor seeks a correlation of 0.95 or better (before fees and expenses) between the Fund's performance and the performance of the Index; a figure of 1.00 would represent perfect correlation.

The Index is owned and was developed by the International Securities Exchange, LLC(R) ("ISE" or "Index Provider"). The Index Provider has contracted with Standard & Poor's Dow Jones Indices to calculate and maintain the Index. The Index provides a benchmark for investors interested in tracking public companies throughout the world that are active in the wind energy industry based on analysis of the products and services offered by those companies. ISE reviews the Index components semi-annually in June and December of each year for eligibility and sets each component's weight in the Index according to the Index methodology. Changes are announced on ISE's publicly available website at www.ise.com on the effective date. As of September 30, 2015, the Index had significant investments in utilities and industrials companies.

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.

Risk Narrative [Text Block]

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.

CURRENCY RISK. The Fund may hold investments that are denominated in non-U.S. currencies, or in securities that provide exposure to such currencies, currency exchange rates or interest rates denominated in such currencies. Changes in currency exchange rates and the relative value of non-U.S. currencies will affect the value of the Fund's investment and the value of Fund shares. Currency exchange rates can be very volatile and can change quickly and unpredictably. As a result, the value of an investment in the Fund may change quickly and without warning and you may lose money.

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 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.

EUROPE RISK. Investments in a single region, even though representing a number of different countries within the region, may be affected by common economic forces and other factors. The Fund is subject to greater risks of adverse events which occur in the European region and may experience greater volatility than a fund that is more broadly diversified geographically. Political or economic disruptions in European countries, even in countries in which the Fund is not invested, may adversely affect security values and thus the Fund's holdings. A significant number of countries in Europe are member states in the European Union (the "EU"), and the member states no longer control their own monetary policies by directing independent interest rates for their currencies. In these member states, the authority to direct monetary policies, including money supply and official interest rates for the Euro, is exercised by the European Central Bank. Furthermore, the European sovereign debt crisis has had, and continues to have, a significant negative impact on the economies of certain European countries and their future economic outlooks.

INDUSTRIALS COMPANIES RISK. Industrials companies convert unfinished goods into finished durables used to manufacture other goods or provide services. Some industrials companies are involved in electrical equipment and components, industrial products, manufactured housing and telecommunications equipment. General risks of industrials companies include the general state of the economy, intense competition, consolidation, domestic and international politics, excess capacity and consumer demand and spending trends. In addition, they may also be significantly affected by overall capital spending levels, economic cycles, technical obsolescence, delays in modernization, labor relations, government regulations and e-commerce initiatives.

LIQUIDITY RISK. Whether or not the equity securities in the Fund are listed on a securities exchange, the principal trading market for certain of the equity securities in the Fund may be in the over-the-counter market. As a result, the existence of a liquid trading market for the equity securities may depend on whether dealers will make a market in the equity securities. There can be no assurance that a market will be made for any of the equity securities, that any market for the equity securities will be maintained or that there will be sufficient liquidity of the equity securities in any markets made. The price at which the equity securities are held in the Fund will be adversely affected if trading markets for the equity securities are limited or absent.

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. 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.

SMALLER COMPANIES RISK. Small and/or mid capitalization companies may be more vulnerable to adverse general market or economic developments, and their securities may be less liquid and may experience greater price volatility than larger, more established companies as a result of several factors, including limited trading volumes, 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.

UTILITIES COMPANIES RISK. General problems of utilities companies include 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, international politics, price and supply fluctuations, volatile interest rates and energy conservation may cause difficulties for utilities. All of such issuers have been experiencing certain of these problems in varying degrees.

WIND ENERGY COMPANIES RISK. Wind energy companies can be significantly affected by obsolescence of existing technology, short product cycles, falling prices and profits, competition from new market entrants and general economic conditions. This can be significantly affected by fluctuations in energy prices and supply and demand of alternative energy fuels, energy conservation, the success of exploration projects and tax and other government regulations. Wind energy companies could be adversely affected by commodity price volatility, changes in exchange rates, imposition of import controls, increased competition, depletion of resources, technological developments and labor relations. In addition, the Fund may include companies affected by industry consolidation, domestic and international politics, excess capacity and consumer demand and spending trends. They may also be significantly affected by overall capital spending levels, economic cycles, delays in modernization, labor relations, government regulations and e-commerce initiatives.

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The bar chart and table below illustrate the annual calendar year returns of the Fund based on net asset value as well as the average annual Fund and Index returns. The bar chart and table provide an indication of the risks of investing in the Fund by showing changes in the Fund's performance from year-to-year and by showing how the Fund's average annual total returns based on net asset value compare to those of the Index and two broad-based 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.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

During the period shown in the chart above:

BEST QUARTER	WORST QUARTER
41.69% (June 30, 2009)	-25.75% (June 30, 2010)

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

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

^[1]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.75%

Total Net Annual Fund Operating Expenses After Fee Waiver and Expense Reimbursement

rr_NetExpensesOverAssets

0.60%

3 Years

rr_ExpenseExampleNoRedemptionYear03

279

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,188

Annual Return 2010

rr_AnnualReturn2010

(31.42%)

Annual Return 2012

rr_AnnualReturn2012

(12.18%)

Annual Return 2014

rr_AnnualReturn2014

(6.61%)

1 Year

rr_AverageAnnualReturnYear01

13.26%

Since Inception

rr_AverageAnnualReturnSinceInception

(10.76%)

1 Year

rr_AverageAnnualReturnYear01

12.10%

Since Inception

rr_AverageAnnualReturnSinceInception

(11.27%)

Risk Return Abstract

rr_RiskReturnAbstract

5 Years

rr_AverageAnnualReturnYear05

2.53%

Label

rr_AverageAnnualReturnLabel

(reflects no deduction for fees, expenses or taxes)

5 Years

rr_AverageAnnualReturnYear05

4.53%

Label

rr_AverageAnnualReturnLabel

(reflects no deduction for fees, expenses or taxes)

5 Years

rr_AverageAnnualReturnYear05

12.18%

Label

rr_AverageAnnualReturnLabel

(reflects no deduction for fees, expenses or taxes)

5 Years

rr_AverageAnnualReturnYear05

7.59%

Risk/Return [Heading]

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SUMMARY INFORMATION

Objective, Primary [Text Block]

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The First Trust Nasdaq Cybersecurity ETF (the "Fund"), formerly First Trust NASDAQ CEA Cybersecurity ETF, 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 CTA Cybersecurity Index(SM) (the "Index").

Expense Narrative [Text Block]

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The following table describes the fees and expenses you may pay if you buy and hold shares of the Fund. Investors purchasing and selling shares may be subject to costs (including customary brokerage commissions) charged by their broker, which are not reflected in the table below.

Operating Expenses Caption [Text]

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

Portfolio Turnover [Text Block]

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The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the fiscal period July 6, 2015 (inception) through September 30, 2015, the Fund's portfolio turnover rate was 7% of the average value of its portfolio.

Expense Example, No Redemption Narrative [Text Block]

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

The example assumes that you invest $10,000 in the Fund for the time periods indicated. The example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain at current levels until July 2, 2017, and thereafter at 0.85% 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:

Strategy Narrative [Text Block]

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The Fund will normally invest at least 90% of its net assets (including investment borrowings) in common stocks or in depositary receipts that comprise the Index. The Fund, using an indexing investment approach, attempts to replicate, before fees and expenses, the performance of the Index. The Fund's investment advisor seeks a correlation of 0.95 or better (before fees and expenses) between the Fund's performance and the performance of the Index; a figure of 1.00 would represent perfect correlation.

The Index is owned by Nasdaq, Inc. (the "Index Provider"). The Index Provider and the Consumer Technology Association ("CTA") have jointly developed the eligibility and selection criteria and rules for the Index. The Index will include securities of companies classified as "cybersecurity" companies by the CTA. The CTA will only give the cybersecurity classification to those companies that meet one of three elements: (1) companies focused on developing technologies that are designed and implemented to protect computer and communication networks from attacks and outside unauthorized use; (2) companies involved in the deployment of technologies for cybersecurity industry use including government, private and public corporations, financial institutions and various other industries; and (3) companies focused on the protection of priority data from being accessed and exploited by unauthorized external parties.

To be included in the Index, a security must meet certain additional criteria, including that it must have a minimum worldwide market capitalization of $250 million, a minimum three-month average daily dollar trading volume of $1 million and a minimum free float of 20%. The term "free float" is used to capture the portion of an issuer's outstanding securities that can be publicly traded, and as a result excludes locked-in securities held by an issuer's affiliates, officers or promoters or securities subject to some other restrictive arrangement that prevents them from being freely traded.

The Index is a modified liquidity weighted index, meaning that it is designed to track the performance of the most liquid companies engaged in the cybersecurity segment of the technology and industrial sectors. The Index accomplishes this by assigning security weights based on the liquidity of the companies comprising the cybersecurity segment. Liquidity is measured by using the three-month average daily dollar trading volume for each company. To provide diversification among the weighting of the constituent companies, the Index first caps the weighting of the securities of the five most liquid companies at 6% each, or collectively 30% of the Index. The excess weight of any capped security is distributed proportionally across the securities of the remaining constituent companies. The securities of the remaining companies are capped at a 3% weight as well. Any security of those remaining constituent companies with a weight in excess of 3% will have that excess weight redistributed proportionally across the securities of any remaining companies.

The Index is calculated and maintained by the Index Provider. The Index Provider evaluates the Index components semi-annually in March and September of each year for eligibility, using market data through the end of February and August, respectively. Eligible components for the Index are identified as such using the eligibility criteria set forth in this prospectus under "Index Information." Securities meeting the criteria are included in the Index. Security additions and deletions are made effective after the close of trading on the third Friday in March and September, respectively. The Index is rebalanced quarterly each March, June, September and December.

As of September 30, 2015, the Index had significant investments in information technology companies. As of December 31, 2015, the Index was comprised of 34 securities from companies located in the United States, the Netherlands, Israel, China, Britain, Ireland, Japan and South Korea, with a significant portion of those companies being of small or mid-capitalizations.

The Fund intends to invest in each security in the Index. The Fund also 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, may 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.

Risk Narrative [Text Block]

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

CYBERSECURITY COMPANIES RISK. Cybersecurity companies are companies that provide products and services intended to protect the integrity of data and network operations for private and public networks, computers and mobile devices. Like other types of technology and industrials companies, cybersecurity 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. These companies may also be smaller and less experienced companies, with limited product lines, markets, qualified personnel or financial resources.

CURRENCY RISK. The Fund may hold investments that are denominated in non-U.S. currencies, or in securities that provide exposure to such currencies, currency exchange rates or interest rates denominated in such currencies. Changes in currency exchange rates and the relative value of non-U.S. currencies will affect the value of the Fund's investment and the value of Fund shares. Currency exchange rates can be very volatile and can change quickly and unpredictably. As a result, the value of an investment in the Fund may change quickly and without warning and you may lose money.

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 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.

INFORMATION TECHNOLOGY COMPANIES RISK. Information technology companies 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 which may be invested in the securities of any one issuer by the diversification requirements imposed by the Internal Revenue Code of 1986, as amended. The Fund may invest a relatively high percentage of its assets in a limited number of issuers. As a result, the Fund may be more susceptible to a single adverse economic or regulatory occurrence affecting one or more of these issuers, experience increased volatility and be highly invested in certain issuers.

NON-U.S. SECURITIES 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.

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. Small and/or mid capitalization companies may be more vulnerable to adverse general market or economic developments, and their securities may be less liquid and may experience greater price volatility than larger, more established companies as a result of several factors, including limited trading volumes, 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.

Performance Narrative [Text Block]

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The Fund does not have a performance history. Once available, the Fund's performance information, and information that gives some indication of the risks of an investment in the Fund by comparing the Fund's performance with a broad measure of market performance, will be available on the Fund's website at www.ftportfolios.com. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

Risk Return Abstract

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Management Fees

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0.60%

Other Expenses

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none

^[2],[6]

Expense Example, No Redemption, 1 Year

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$ 61

Risk/Return [Heading]

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SUMMARY INFORMATION

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The First Trust Nasdaq Smartphone Index Fund (the "Fund"), formerly First Trust NASDAQ CEA Smartphone Index 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 CTA Smartphone Index(SM) (the "Index").

Expense Narrative [Text Block]

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.

Operating Expenses Caption [Text]

rr_OperatingExpensesCaption

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

Portfolio Turnover [Text Block]

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 Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the Fund's performance. During the most recent fiscal year, the Fund's portfolio turnover rate was 28% of the average value of its portfolio.

Expense Example, No Redemption Narrative [Text Block]

rr_ExpenseExampleNoRedemptionNarrativeTextBlock

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, 2017, and thereafter at 0.95% 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:

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The Fund will normally invest at least 90% of its net assets (including investment borrowings) in common stocks or in depositary receipts representing securities in the Index. The Fund's investment advisor seeks to match the performance of the Index (before the Fund's fees and expenses).

The Fund, using an indexing investment approach, attempts to replicate, before fees and expenses, the performance of the Index. The Fund's investment advisor seeks a correlation of 0.95 or better (before fees and expenses) between the Fund's performance and the performance of the Index; a figure of 1.00 would represent perfect correlation.

The Index is owned by Nasdaq, Inc. (the "Index Provider"). The Index Provider and the Consumer Technology Association have jointly developed the eligibility and selection criteria and rules for the Index. The Index is calculated and maintained by the Index Provider. The Index is designed to track the performance of companies engaged in the Smartphone segment of the telecommunications and technology sectors. The Index includes companies primarily involved in the building, design and distribution of handsets, hardware, software and mobile networks associated with the development, sale and usage of Smartphones. The Index Provider defines a Smartphone as a wireless, mobile communication device offering advanced capabilities and functionalities, including web access, through the use of an identifiable operating system.

The Index uses a modified equal dollar weighting methodology. The Index Provider evaluates the Index components semi-annually in March and September of each year for eligibility, using market data through the end of February and August, respectively. Eligible components for the Index are identified as such using the eligibility criteria set forth in this prospectus under "Index Information." As of September 30, 2015, the Index had significant investments in information technology companies. Changes to the Index are made effective after the close of trading on the third Friday in March and September. The Index is rebalanced quarterly, each March, June, September and December. As of December 31, 2015, there were 53 securities that comprised the Index.

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.

Risk Narrative [Text Block]

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.

ASIA RISK. The Fund invests, in part, in securities issued by companies operating in Asia, and is therefore subject to certain risks associated specifically with Asia. For example, some of the currencies of these countries have experienced devaluations relative to the U.S. dollar, and adjustments have been made periodically in certain of such currencies. Certain countries, such as Indonesia, face serious exchange constraints. Jurisdictional disputes also exist, for example, between South Korea and North Korea. The Tokyo stock market, as measured by the Tokyo Stock Price Index, has been volatile. Declines in the Tokyo stock market have made the country's banks and financial institutions vulnerable. Furthermore, the natural disasters that have impacted Japan and the ongoing recovery efforts have had a negative effect on Japan's economy, and may continue to do so.