Thornburg Premium Income Builder ETF New and Smaller Sized Fund Risk [Member] Investment Adviser Risk [Member] ETF Structure Risks [Member] Equity Risk [Member] Options Strategy Risk [Member] Foreign Investment Risk [Member] Foreign Currency Risk [Member] Emerging Markets Risk [Member] Risks of Investing in Depositary Receipts [Member] Real Estate Risk [Member] Derivatives Risk [Member] Focused Investment Risk [Member] Equity-Linked Notes Risk [Member] Risks Affecting Convertible Debt Obligations [Member] Risks of Investing in U.S. Government Obligations [Member] Risks of Debt Issued by Foreign Governments [Member] Credit Risk [Member] High Yield Risk [Member] Interest Rate Risk [Member] Prepayment and Extension Risk [Member] Risks Affecting Mortgage-Backed Securities and Other Asset-Backed Securities [Member] Business Development Company ("BDC") Risk [Member] Market and Economic Risk [Member] Risks Affecting Specific Countries or Regions [Member] Risks Affecting Specific Issuers [Member] Liquidity Risk [Member] Cybersecurity and Operational Risk [Member] Thornburg Premium Income Builder ETF [Member] Thornburg Premium Income Builder ETF Thornburg Premium Income Builder ETF [Member] Cybersecurity and Operational Risk. Liquidity Risk. Risks Affecting Specific Issuers. Risks Affecting Specific Countries or Regions. Market and Economic Risk. Business Development Company ("BDC") Risk Risks Affecting Mortgage-Backed Securities and Other Asset-Backed Securities. Prepayment and Extension Risk. High Yield Risk. Risks of Debt Issued by Foreign Governments. Risks of Investing in U.S. Government Obligations. Risks Affecting Convertible Debt Obligations. Equity-Linked Notes Risk. Focused Investment Risk. Derivatives Risk. Real Estate Risk. Risks of Investing in Depositary Receipts. Emerging Markets Risk. Foreign Investment Risk. Options Strategy Risk. Equity Risk. ETF Structure Risks. Investment Adviser Risk. New and Smaller Sized Fund Risk. Foreign Currency Risk.