110001 - Disclosure - First Trust Capital Strength ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 110002 - Disclosure - First Trust Capital Strength ETF Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 110003 - Disclosure - First Trust Capital Strength ETF Investment Strategy link:presentationLink link:definitionLink link:calculationLink 110004 - Disclosure - First Trust Capital Strength ETF Investment Risks link:presentationLink link:definitionLink link:calculationLink 110005 - Disclosure - First Trust Capital Strength ETF Performance Management link:presentationLink link:definitionLink link:calculationLink 120010 - Disclosure - First Trust Capital Strength ETF Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 120020 - Disclosure - First Trust Capital Strength ETF Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 120030 - Disclosure - First Trust Capital Strength ETF Expense Example link:presentationLink link:definitionLink link:calculationLink 120040 - Disclosure - First Trust Capital Strength ETF Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 120045 - Disclosure - First Trust Capital Strength ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 120050 - Disclosure - First Trust Capital Strength ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 120060 - Disclosure - First Trust Capital Strength ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 120070 - Disclosure - First Trust Capital Strength ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 110000 - Disclosure - First Trust Capital Strength ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 210001 - Disclosure - First Trust Dow Jones Internet Index Fund Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 210002 - Disclosure - First Trust Dow Jones Internet Index Fund Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 210003 - Disclosure - First Trust Dow Jones Internet Index Fund Investment Strategy link:presentationLink link:definitionLink link:calculationLink 210004 - Disclosure - First Trust Dow Jones Internet Index Fund Investment Risks link:presentationLink link:definitionLink link:calculationLink 210005 - Disclosure - First Trust Dow Jones Internet Index Fund Performance Management link:presentationLink link:definitionLink link:calculationLink 220010 - Disclosure - First Trust Dow Jones Internet Index Fund Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 220020 - Disclosure - First Trust Dow Jones Internet Index Fund Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 220030 - Disclosure - First Trust Dow Jones Internet Index Fund Expense Example link:presentationLink link:definitionLink link:calculationLink 220040 - Disclosure - First Trust Dow Jones Internet Index Fund Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 220045 - Disclosure - First Trust Dow Jones Internet Index Fund Risks Data link:presentationLink link:definitionLink link:calculationLink 220050 - Disclosure - First Trust Dow Jones Internet Index Fund Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 220060 - Disclosure - First Trust Dow Jones Internet Index Fund Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 220070 - Disclosure - First Trust Dow Jones Internet Index Fund Market Index Performance link:presentationLink link:definitionLink link:calculationLink 210000 - Disclosure - First Trust Dow Jones Internet Index Fund N-1A Cover link:presentationLink link:definitionLink link:calculationLink 310001 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 310002 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 310003 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund Investment Strategy link:presentationLink link:definitionLink link:calculationLink 310004 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund Investment Risks link:presentationLink link:definitionLink link:calculationLink 310005 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund Performance Management link:presentationLink link:definitionLink link:calculationLink 320010 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 320020 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 320030 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund Expense Example link:presentationLink link:definitionLink link:calculationLink 320040 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 320045 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund Risks Data link:presentationLink link:definitionLink link:calculationLink 320050 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 320060 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 320070 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund Market Index Performance link:presentationLink link:definitionLink link:calculationLink 310000 - Disclosure - First Trust Dow Jones Select MicroCap Index Fund N-1A Cover link:presentationLink link:definitionLink link:calculationLink 410001 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 410002 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 410003 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund Investment Strategy link:presentationLink link:definitionLink link:calculationLink 410004 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund Investment Risks link:presentationLink link:definitionLink link:calculationLink 410005 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund Performance Management link:presentationLink link:definitionLink link:calculationLink 420010 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 420020 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 420030 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund Expense Example link:presentationLink link:definitionLink link:calculationLink 420040 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 420045 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund Risks Data link:presentationLink link:definitionLink link:calculationLink 420050 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 420060 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 420070 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund Market Index Performance link:presentationLink link:definitionLink link:calculationLink 410000 - Disclosure - First Trust Morningstar Dividend Leaders Index Fund N-1A Cover link:presentationLink link:definitionLink link:calculationLink 510001 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 510002 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 510003 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund Investment Strategy link:presentationLink link:definitionLink link:calculationLink 510004 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund Investment Risks link:presentationLink link:definitionLink link:calculationLink 510005 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund Performance Management link:presentationLink link:definitionLink link:calculationLink 520010 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 520020 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 520030 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund Expense Example link:presentationLink link:definitionLink link:calculationLink 520040 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 520045 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund Risks Data link:presentationLink link:definitionLink link:calculationLink 520050 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 520060 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 520070 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund Market Index Performance link:presentationLink link:definitionLink link:calculationLink 510000 - Disclosure - First Trust NASDAQ-100 Ex-Technology Sector Index Fund N-1A Cover link:presentationLink link:definitionLink link:calculationLink 610001 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 610002 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 610003 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund Investment Strategy link:presentationLink link:definitionLink link:calculationLink 610004 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund Investment Risks link:presentationLink link:definitionLink link:calculationLink 610005 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund Performance Management link:presentationLink link:definitionLink link:calculationLink 620010 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 620020 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 620030 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund Expense Example link:presentationLink link:definitionLink link:calculationLink 620040 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 620045 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund Risks Data link:presentationLink link:definitionLink link:calculationLink 620050 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 620060 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 620070 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund Market Index Performance link:presentationLink link:definitionLink link:calculationLink 610000 - Disclosure - First Trust NASDAQ-100-Technology Sector Index Fund N-1A Cover link:presentationLink link:definitionLink link:calculationLink 710001 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 710002 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 710003 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund Investment Strategy link:presentationLink link:definitionLink link:calculationLink 710004 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund Investment Risks link:presentationLink link:definitionLink link:calculationLink 710005 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund Performance Management link:presentationLink link:definitionLink link:calculationLink 720010 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 720020 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 720030 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund Expense Example link:presentationLink link:definitionLink link:calculationLink 720040 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 720045 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund Risks Data link:presentationLink link:definitionLink link:calculationLink 720050 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 720060 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 720070 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund Market Index Performance link:presentationLink link:definitionLink link:calculationLink 710000 - Disclosure - First Trust NASDAQ ABA Community Bank Index Fund N-1A Cover link:presentationLink link:definitionLink link:calculationLink 810001 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 810002 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 810003 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund Investment Strategy link:presentationLink link:definitionLink link:calculationLink 810004 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund Investment Risks link:presentationLink link:definitionLink link:calculationLink 810005 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund Performance Management link:presentationLink link:definitionLink link:calculationLink 820010 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 820020 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 820030 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund Expense Example link:presentationLink link:definitionLink link:calculationLink 820040 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 820045 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund Risks Data link:presentationLink link:definitionLink link:calculationLink 820050 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 820060 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 820070 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund Market Index Performance link:presentationLink link:definitionLink link:calculationLink 810000 - Disclosure - First Trust NASDAQ Clean Edge Green Energy Index Fund N-1A Cover link:presentationLink link:definitionLink link:calculationLink 910001 - Disclosure - First Trust Natural Gas ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 910002 - Disclosure - First Trust Natural Gas ETF Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 910003 - Disclosure - First Trust Natural Gas ETF Investment Strategy link:presentationLink link:definitionLink link:calculationLink 910004 - Disclosure - First Trust Natural Gas ETF Investment Risks link:presentationLink link:definitionLink link:calculationLink 910005 - Disclosure - First Trust Natural Gas ETF Performance Management link:presentationLink link:definitionLink link:calculationLink 920010 - Disclosure - First Trust Natural Gas ETF Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 920020 - Disclosure - First Trust Natural Gas ETF Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 920030 - Disclosure - First Trust Natural Gas ETF Expense Example link:presentationLink link:definitionLink link:calculationLink 920040 - Disclosure - First Trust Natural Gas ETF Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 920045 - Disclosure - First Trust Natural Gas ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 920050 - Disclosure - First Trust Natural Gas ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 920060 - Disclosure - First Trust Natural Gas ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 920070 - Disclosure - First Trust Natural Gas ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 910000 - Disclosure - First Trust Natural Gas ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 1010001 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 1010002 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 1010003 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund Investment Strategy link:presentationLink link:definitionLink link:calculationLink 1010004 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund Investment Risks link:presentationLink link:definitionLink link:calculationLink 1010005 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund Performance Management link:presentationLink link:definitionLink link:calculationLink 1020010 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 1020020 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 1020030 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund Expense Example link:presentationLink link:definitionLink link:calculationLink 1020040 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 1020045 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund Risks Data link:presentationLink link:definitionLink link:calculationLink 1020050 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1020060 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1020070 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund Market Index Performance link:presentationLink link:definitionLink link:calculationLink 1010000 - Disclosure - First Trust NYSE Arca Biotechnology Index Fund N-1A Cover link:presentationLink link:definitionLink link:calculationLink 1110001 - Disclosure - First Trust S and P REIT Index Fund Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 1110002 - Disclosure - First Trust S and P REIT Index Fund Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 1110003 - Disclosure - First Trust S and P REIT Index Fund Investment Strategy link:presentationLink link:definitionLink link:calculationLink 1110004 - Disclosure - First Trust S and P REIT Index Fund Investment Risks link:presentationLink link:definitionLink link:calculationLink 1110005 - Disclosure - First Trust S and P REIT Index Fund Performance Management link:presentationLink link:definitionLink link:calculationLink 1120010 - Disclosure - First Trust S and P REIT Index Fund Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 1120020 - Disclosure - First Trust S and P REIT Index Fund Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 1120030 - Disclosure - First Trust S and P REIT Index Fund Expense Example link:presentationLink link:definitionLink link:calculationLink 1120040 - Disclosure - First Trust S and P REIT Index Fund Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 1120045 - Disclosure - First Trust S and P REIT Index Fund Risks Data link:presentationLink link:definitionLink link:calculationLink 1120050 - Disclosure - First Trust S and P REIT Index Fund Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1120060 - Disclosure - First Trust S and P REIT Index Fund Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1120070 - Disclosure - First Trust S and P REIT Index Fund Market Index Performance link:presentationLink link:definitionLink link:calculationLink 1110000 - Disclosure - First Trust S and P REIT Index Fund N-1A Cover link:presentationLink link:definitionLink link:calculationLink 1210001 - Disclosure - First Trust US Equity Opportunities ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 1210002 - Disclosure - First Trust US Equity Opportunities ETF Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 1210003 - Disclosure - First Trust US Equity Opportunities ETF Investment Strategy link:presentationLink link:definitionLink link:calculationLink 1210004 - Disclosure - First Trust US Equity Opportunities ETF Investment Risks link:presentationLink link:definitionLink link:calculationLink 1210005 - Disclosure - First Trust US Equity Opportunities ETF Performance Management link:presentationLink link:definitionLink link:calculationLink 1220010 - Disclosure - First Trust US Equity Opportunities ETF Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 1220020 - Disclosure - First Trust US Equity Opportunities ETF Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 1220030 - Disclosure - First Trust US Equity Opportunities ETF Expense Example link:presentationLink link:definitionLink link:calculationLink 1220040 - Disclosure - First Trust US Equity Opportunities ETF Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 1220045 - Disclosure - First Trust US Equity Opportunities ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 1220050 - Disclosure - First Trust US Equity Opportunities ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1220060 - Disclosure - First Trust US Equity Opportunities ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1220070 - Disclosure - First Trust US Equity Opportunities ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 1210000 - Disclosure - First Trust US Equity Opportunities ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 1310001 - Disclosure - First Trust Value Line Dividend Index Fund Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 1310002 - Disclosure - First Trust Value Line Dividend Index Fund Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 1310003 - Disclosure - First Trust Value Line Dividend Index Fund Investment Strategy link:presentationLink link:definitionLink link:calculationLink 1310004 - Disclosure - First Trust Value Line Dividend Index Fund Investment Risks link:presentationLink link:definitionLink link:calculationLink 1310005 - Disclosure - First Trust Value Line Dividend Index Fund Performance Management link:presentationLink link:definitionLink link:calculationLink 1320010 - Disclosure - First Trust Value Line Dividend Index Fund Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 1320020 - Disclosure - First Trust Value Line Dividend Index Fund Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 1320030 - Disclosure - First Trust Value Line Dividend Index Fund Expense Example link:presentationLink link:definitionLink link:calculationLink 1320040 - Disclosure - First Trust Value Line Dividend Index Fund Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 1320045 - Disclosure - First Trust Value Line Dividend Index Fund Risks Data link:presentationLink link:definitionLink link:calculationLink 1320050 - Disclosure - First Trust Value Line Dividend Index Fund Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1320060 - Disclosure - First Trust Value Line Dividend Index Fund Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1320070 - Disclosure - First Trust Value Line Dividend Index Fund Market Index Performance link:presentationLink link:definitionLink link:calculationLink 1310000 - Disclosure - First Trust Value Line Dividend Index Fund N-1A Cover link:presentationLink link:definitionLink link:calculationLink 1410001 - Disclosure - First Trust Water ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 1410002 - Disclosure - First Trust Water ETF Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 1410003 - Disclosure - First Trust Water ETF Investment Strategy link:presentationLink link:definitionLink link:calculationLink 1410004 - Disclosure - First Trust Water ETF Investment Risks link:presentationLink link:definitionLink link:calculationLink 1410005 - Disclosure - First Trust Water ETF Performance Management link:presentationLink link:definitionLink link:calculationLink 1420010 - Disclosure - First Trust Water ETF Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 1420020 - Disclosure - First Trust Water ETF Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 1420030 - Disclosure - First Trust Water ETF Expense Example link:presentationLink link:definitionLink link:calculationLink 1420040 - Disclosure - First Trust Water ETF Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 1420045 - Disclosure - First Trust Water ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 1420050 - Disclosure - First Trust Water ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1420060 - Disclosure - First Trust Water ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1420070 - Disclosure - First Trust Water ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 1410000 - Disclosure - First Trust Water ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 1510001 - Disclosure - First Trust Dow 30 Equal Weight ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 1510002 - Disclosure - First Trust Dow 30 Equal Weight ETF Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 1510003 - Disclosure - First Trust Dow 30 Equal Weight ETF Investment Strategy link:presentationLink link:definitionLink link:calculationLink 1510004 - Disclosure - First Trust Dow 30 Equal Weight ETF Investment Risks link:presentationLink link:definitionLink link:calculationLink 1510005 - Disclosure - First Trust Dow 30 Equal Weight ETF Performance Management link:presentationLink link:definitionLink link:calculationLink 1520010 - Disclosure - First Trust Dow 30 Equal Weight ETF Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 1520020 - Disclosure - First Trust Dow 30 Equal Weight ETF Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 1520030 - Disclosure - First Trust Dow 30 Equal Weight ETF Expense Example link:presentationLink link:definitionLink link:calculationLink 1520040 - Disclosure - First Trust Dow 30 Equal Weight ETF Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 1520045 - Disclosure - First Trust Dow 30 Equal Weight ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 1520050 - Disclosure - First Trust Dow 30 Equal Weight ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1520060 - Disclosure - First Trust Dow 30 Equal Weight ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1520070 - Disclosure - First Trust Dow 30 Equal Weight ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 1510000 - Disclosure - First Trust Dow 30 Equal Weight ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 1610001 - Disclosure - First Trust Lunt US Factor Rotation ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 1610002 - Disclosure - First Trust Lunt US Factor Rotation ETF Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 1610003 - Disclosure - First Trust Lunt US Factor Rotation ETF Investment Strategy link:presentationLink link:definitionLink link:calculationLink 1610004 - Disclosure - First Trust Lunt US Factor Rotation ETF Investment Risks link:presentationLink link:definitionLink link:calculationLink 1610005 - Disclosure - First Trust Lunt US Factor Rotation ETF Performance Management link:presentationLink link:definitionLink link:calculationLink 1620010 - Disclosure - First Trust Lunt US Factor Rotation ETF Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 1620020 - Disclosure - First Trust Lunt US Factor Rotation ETF Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 1620030 - Disclosure - First Trust Lunt US Factor Rotation ETF Expense Example link:presentationLink link:definitionLink link:calculationLink 1620040 - Disclosure - First Trust Lunt US Factor Rotation ETF Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 1620045 - Disclosure - First Trust Lunt US Factor Rotation ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 1620050 - Disclosure - First Trust Lunt US Factor Rotation ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1620060 - Disclosure - First Trust Lunt US Factor Rotation ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1620070 - Disclosure - First Trust Lunt US Factor Rotation ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 1610000 - Disclosure - First Trust Lunt US Factor Rotation ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 1710001 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 1710002 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 1710003 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF Investment Strategy link:presentationLink link:definitionLink link:calculationLink 1710004 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF Investment Risks link:presentationLink link:definitionLink link:calculationLink 1710005 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF Performance Management link:presentationLink link:definitionLink link:calculationLink 1720010 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 1720020 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 1720030 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF Expense Example link:presentationLink link:definitionLink link:calculationLink 1720040 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 1720045 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 1720050 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1720060 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1720070 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 1710000 - Disclosure - FT Vest Gold Strategy Quarterly Buffer ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 1810001 - Disclosure - FT Vest Gold Strategy Target Income ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 1810002 - Disclosure - FT Vest Gold Strategy Target Income ETF Fees and Expenses link:presentationLink 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Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 1920045 - Disclosure - First Trust Dividend Strength ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 1920050 - Disclosure - First Trust Dividend Strength ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1920060 - Disclosure - First Trust Dividend Strength ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 1920070 - Disclosure - First Trust Dividend Strength ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 1910000 - Disclosure - First Trust Dividend Strength ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 2010001 - Disclosure - First Trust Indxx Aerospace and Defense ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 2010002 - Disclosure - First Trust Indxx Aerospace and Defense ETF Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 2010003 - Disclosure - First Trust Indxx Aerospace and Defense ETF Investment Strategy link:presentationLink link:definitionLink link:calculationLink 2010004 - Disclosure - First Trust Indxx Aerospace and Defense ETF Investment Risks link:presentationLink link:definitionLink link:calculationLink 2010005 - Disclosure - First Trust Indxx Aerospace and Defense ETF Performance Management link:presentationLink link:definitionLink link:calculationLink 2020010 - Disclosure - First Trust Indxx Aerospace and Defense ETF Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 2020020 - Disclosure - First Trust Indxx Aerospace and Defense ETF Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 2020030 - Disclosure - First Trust Indxx Aerospace and Defense ETF Expense Example link:presentationLink link:definitionLink link:calculationLink 2020040 - Disclosure - First Trust Indxx Aerospace and Defense ETF Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 2020045 - Disclosure - First Trust Indxx Aerospace and Defense ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 2020050 - Disclosure - First Trust Indxx Aerospace and Defense ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2020060 - Disclosure - First Trust Indxx Aerospace and Defense ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2020070 - Disclosure - First Trust Indxx Aerospace and Defense ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 2010000 - Disclosure - First Trust Indxx Aerospace and Defense ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 2110001 - Disclosure - First Trust Growth Strength ETF Investment 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link:presentationLink link:definitionLink link:calculationLink 2120040 - Disclosure - First Trust Growth Strength ETF Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 2120045 - Disclosure - First Trust Growth Strength ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 2120050 - Disclosure - First Trust Growth Strength ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2120060 - Disclosure - First Trust Growth Strength ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2120070 - Disclosure - First Trust Growth Strength ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 2110000 - Disclosure - First Trust Growth Strength ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 2210001 - Disclosure - First Trust Bloomberg Inflation Sensitive Equity ETF Investment Objectives and 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S&P 500 Diversified Free Cash Flow ETF Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 2320020 - Disclosure - First Trust S&P 500 Diversified Free Cash Flow ETF Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 2320030 - Disclosure - First Trust S&P 500 Diversified Free Cash Flow ETF Expense Example link:presentationLink link:definitionLink link:calculationLink 2320040 - Disclosure - First Trust S&P 500 Diversified Free Cash Flow ETF Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 2320045 - Disclosure - First Trust S&P 500 Diversified Free Cash Flow ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 2320050 - Disclosure - First Trust S&P 500 Diversified Free Cash Flow ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2320060 - Disclosure - First Trust S&P 500 Diversified Free Cash Flow ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2320070 - Disclosure - First Trust S&P 500 Diversified Free Cash Flow ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 2310000 - Disclosure - First Trust S&P 500 Diversified Free Cash Flow ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 2410001 - Disclosure - First Trust WCM Developing World Equity ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 2410002 - Disclosure - First Trust WCM Developing World Equity ETF Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 2410003 - Disclosure - First Trust WCM Developing World Equity ETF Investment Strategy link:presentationLink link:definitionLink link:calculationLink 2410004 - Disclosure - First Trust WCM Developing World Equity ETF Investment Risks link:presentationLink link:definitionLink link:calculationLink 2410005 - Disclosure - First Trust WCM Developing World Equity ETF Performance Management link:presentationLink link:definitionLink link:calculationLink 2420010 - Disclosure - First Trust WCM Developing World Equity ETF Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 2420020 - Disclosure - First Trust WCM Developing World Equity ETF Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 2420030 - Disclosure - First Trust WCM Developing World Equity ETF Expense Example link:presentationLink link:definitionLink link:calculationLink 2420040 - Disclosure - First Trust WCM Developing World Equity ETF Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 2420045 - Disclosure - First Trust WCM Developing World Equity ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 2420050 - Disclosure - First Trust WCM Developing World Equity ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2420060 - Disclosure - First Trust WCM Developing World Equity ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2420070 - Disclosure - First Trust WCM Developing World Equity ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 2410000 - Disclosure - First Trust WCM Developing World Equity ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 2510001 - Disclosure - First Trust WCM International Equity ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 2510002 - Disclosure - First Trust WCM International Equity ETF Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 2510003 - Disclosure - First Trust WCM International Equity ETF Investment Strategy link:presentationLink link:definitionLink link:calculationLink 2510004 - Disclosure - First 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link:calculationLink 2520050 - Disclosure - First Trust WCM International Equity ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2520060 - Disclosure - First Trust WCM International Equity ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2520070 - Disclosure - First Trust WCM International Equity ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 2510000 - Disclosure - First Trust WCM International Equity ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 2610001 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 2610002 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 2610003 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF Investment Strategy link:presentationLink link:definitionLink link:calculationLink 2610004 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF Investment Risks link:presentationLink link:definitionLink link:calculationLink 2610005 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF Performance Management link:presentationLink link:definitionLink link:calculationLink 2620010 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 2620020 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 2620030 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF Expense Example link:presentationLink link:definitionLink link:calculationLink 2620040 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 2620045 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 2620050 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2620060 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2620070 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 2610000 - Disclosure - FT Vest Bitcoin Strategy & Target Income ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 2710001 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 2710002 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 2710003 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April Investment Strategy link:presentationLink link:definitionLink link:calculationLink 2710004 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April Investment Risks link:presentationLink link:definitionLink link:calculationLink 2710005 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April Performance Management link:presentationLink link:definitionLink link:calculationLink 2720010 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 2720020 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 2720030 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April Expense Example link:presentationLink link:definitionLink link:calculationLink 2720040 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 2720045 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April Risks Data link:presentationLink link:definitionLink link:calculationLink 2720050 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2720060 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2720070 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April Market Index Performance link:presentationLink link:definitionLink link:calculationLink 2710000 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - April N-1A Cover link:presentationLink link:definitionLink link:calculationLink 2810001 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 2810002 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 2810003 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July Investment Strategy link:presentationLink link:definitionLink link:calculationLink 2810004 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July Investment Risks link:presentationLink link:definitionLink link:calculationLink 2810005 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July Performance Management link:presentationLink link:definitionLink link:calculationLink 2820010 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 2820020 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 2820030 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July Expense Example link:presentationLink link:definitionLink link:calculationLink 2820040 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 2820045 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July Risks Data link:presentationLink link:definitionLink link:calculationLink 2820050 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2820060 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2820070 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July Market Index Performance link:presentationLink link:definitionLink link:calculationLink 2810000 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - July N-1A Cover link:presentationLink link:definitionLink link:calculationLink 2910001 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 2910002 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 2910003 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October Investment Strategy link:presentationLink link:definitionLink link:calculationLink 2910004 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October Investment Risks link:presentationLink link:definitionLink link:calculationLink 2910005 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October Performance Management link:presentationLink link:definitionLink link:calculationLink 2920010 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 2920020 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 2920030 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October Expense Example link:presentationLink link:definitionLink link:calculationLink 2920040 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 2920045 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October Risks Data link:presentationLink link:definitionLink link:calculationLink 2920050 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2920060 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 2920070 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October Market Index Performance link:presentationLink link:definitionLink link:calculationLink 2910000 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - October N-1A Cover link:presentationLink link:definitionLink link:calculationLink 3010001 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 3010002 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 3010003 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF Investment Strategy link:presentationLink link:definitionLink link:calculationLink 3010004 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF Investment Risks link:presentationLink link:definitionLink link:calculationLink 3010005 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF Performance Management link:presentationLink link:definitionLink link:calculationLink 3020010 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 3020020 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 3020030 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF Expense Example link:presentationLink link:definitionLink link:calculationLink 3020040 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 3020045 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF Risks Data link:presentationLink link:definitionLink link:calculationLink 3020050 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 3020060 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 3020070 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF Market Index Performance link:presentationLink link:definitionLink link:calculationLink 3010000 - Disclosure - First Trust Nasdaq-100 Select Equal Weight ETF N-1A Cover link:presentationLink link:definitionLink link:calculationLink 3110001 - Disclosure - FT Vest Laddered Autocallable Barrier & Income ETF Investment Objectives and Goals link:presentationLink link:definitionLink link:calculationLink 3110002 - Disclosure - FT Vest Laddered Autocallable Barrier & Income ETF Fees and Expenses link:presentationLink link:definitionLink link:calculationLink 3110003 - Disclosure - FT Vest Laddered Autocallable Barrier & Income ETF Investment Strategy link:presentationLink link:definitionLink link:calculationLink 3110004 - Disclosure - FT Vest Laddered Autocallable Barrier & Income ETF Investment Risks 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Vest Bitcoin Strategy Floor15 ETF - January Investment Strategy link:presentationLink link:definitionLink link:calculationLink 3210004 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - January Investment Risks link:presentationLink link:definitionLink link:calculationLink 3210005 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - January Performance Management link:presentationLink link:definitionLink link:calculationLink 3220010 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - January Shareholder Fees link:presentationLink link:definitionLink link:calculationLink 3220020 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - January Annual Fund Operating Expenses link:presentationLink link:definitionLink link:calculationLink 3220030 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - January Expense Example link:presentationLink link:definitionLink link:calculationLink 3220040 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - January Expense Example, No Redemption link:presentationLink link:definitionLink link:calculationLink 3220045 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - January Risks Data link:presentationLink link:definitionLink link:calculationLink 3220050 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - January Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 3220060 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - January Average Annual Total Returns link:presentationLink link:definitionLink link:calculationLink 3220070 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - January Market Index Performance link:presentationLink link:definitionLink link:calculationLink 3210000 - Disclosure - FT Vest Bitcoin Strategy Floor15 ETF - January N-1A Cover link:presentationLink link:definitionLink link:calculationLink First Trust Capital Strength ETF S000012555 [Member] C000034137 [Member] The Capital Strength(TM) Index (reflects no deduction for fees, expenses or taxes)[Member] S&P 500® 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