Defiance Daily Target 2X Long SIL ETF SIL Risks [Member] Asset Class Risk [Member] Commodity Risk [Member] Exposure to Related Markets Risk [Member] Silver Risk [Member] Market Capitalization Risks [Member] Large-Capitalization Companies Risk [Member] Mid-Capitalization Companies Risk [Member] Small-Capitalization Companies Risk [Member] Currency Risk [Member] Focus Risk [Member] Risks Related to Investing in the Materials Sector [Member] Risks Related to Investing in the Metals and Mining Industry [Member] Foreign Securities Risk [Member] Risk of Investing in Brazil [Member] Risk of Investing in Canada [Member] Risk of Investing in Developed Markets [Member] Risk of Investing in Emerging Markets [Member] Risk of Investing in Mexico [Member] Indexing Strategy Risk [Member] Index-Related Risk [Member] Management Risk [Member] Tracking Error Risk [Member] International Closed Market Trading Risk [Member] Investable Universe of Companies Risk [Member] Issuer Risk [Member] Non-Diversification Risk [Member] Securities Lending Risk [Member] Trading Halt Risk [Member] Valuation Risk [Member] Single Issuer Risk [Member] Compounding and Market Volatility Risk [Member] Daily Correlation/Tracking Risk [Member] Leverage Risk [Member] Derivatives Risk [Member] Swap Agreements [Member] Options Contracts [Member] Counterparty Risk [Member] Intra-Day Investment Risk [Member] Fixed Income Securities Risk [Member] Rebalancing Risk [Member] ETF Risks [Member] Authorized Participants, Market Makers, and Liquidity Providers Concentration Risk [Member] Cash Redemption Risk [Member] Costs of Buying or Selling Shares [Member] Shares May Trade at Prices Other Than NAV [Member] Trading [Member] Liquidity Risk [Member] Economic and Market Risk [Member] High Portfolio Turnover Risk [Member] Tracking Error Risk 1 [Member] Liquidity Risk 1 [Member] Money Market Instrument Risk [Member] New Fund Risk [Member] Trading Halt Risk 1 [Member] Operational Risk [Member] U.S. Government and U.S. Agency Obligations Risk [Member] Tax Risk [Member] Defiance Daily Target 2X Long SILJ ETF SILJ Risks [Member] Concentration Risk [Member] Emerging Markets Risk [Member] Equity Securities Risk [Member] Foreign Investment Risk [Member] Depositary Receipts Risk [Member] Foreign Market and Trading Risk [Member] Political and Economic Risk [Member] Reliance on Trading Partners Risk [Member] Geographic Concentration Risk [Member] Canada-Specific Risk [Member] Index Provider Risk [Member] Inflation Risk [Member] Metals and Mining Companies Risk [Member] Passive Investment Risk [Member] Security Issuer Risk [Member] Silver Exploration and Production Industry Concentration Risk [Member] Smaller Companies Risk [Member] Defiance Daily Target 2X Long SIL ETF [Member] Defiance Daily Target 2X Long SILJ ETF [Member] Defiance Daily Target 2X Long SIL ETF. Defiance Daily Target 2X Long SIL ETF. Defiance Daily Target 2X Long SILJ ETF. Defiance Daily Target 2X Long SILJ ETF. Tax Risk. U.S. Government and U.S. Agency Obligations Risk. Operational Risk. Trading Halt Risk. New Fund Risk. Money Market Instrument Risk. Liquidity Risk. Tracking Error Risk. High Portfolio Turnover Risk. Economic and Market Risk. Trading. Shares May Trade at Prices Other Than NAV. Costs of Buying or Selling Shares. Cash Redemption Risk. Authorized Participants, Market Makers, and Liquidity Providers Concentration Risk. ETF Risks. Rebalancing Risk. Fixed Income Securities Risk. Intra-Day Investment Risk. Counterparty Risk. Options Contracts. Swap Agreements. Derivatives Risk. Leverage Risk. Daily Correlation/Tracking Risk. Compounding and Market Volatility Risk. Single Issuer Risk. Valuation Risk. Smaller Companies Risk. Silver Exploration and Production Industry Concentration Risk. Security Issuer Risk. Passive Investment Risk. Non-Diversification Risk. Metals and Mining Companies Risk. Inflation Risk. Index Provider Risk. Canada-Specific Risk. Reliance on Trading Partners Risk. Political and Economic Risk. Foreign Securities Risk. Foreign Market and Trading Risk. Depositary Receipts Risk. Currency Risk. Foreign Investment Risk. Equity Securities Risk. Emerging Markets Risk. Concentration Risk. SILJ Risks. Securities Lending Risk. Issuer Risk. Investable Universe of Companies Risk. International Closed Market Trading Risk. Management Risk. Index-Related Risk. Indexing Strategy Risk. Risk of Investing in Mexico. Risk of Investing in Emerging Markets. Risk of Investing in Developed Markets. Risk of Investing in Canada. Risk of Investing in Brazil. Risks Related to Investing in the Metals and Mining Industry. Risks Related to Investing in the Materials Sector. Focus Risk. Small-Capitalization Companies Risk. Mid-Capitalization Companies Risk. Large-Capitalization Companies Risk. Market Capitalization Risks. Silver Risk. Exposure to Related Markets Risk. Commodity Risk. Asset Class Risk. SIL Risks. Liquidity Risk. Trading Halt Risk. Tracking Error Risk.