Retail [Member] Thornburg Investment Income Builder Fund Convertible Debt Obligation Risk [Member] Credit Risk [Member] Cybersecurity and Operational Risk [Member] Developing Country Risk [Member] Equity Risk [Member] Foreign Currency Risk [Member] Foreign Government Obligations Risk [Member] Foreign Investment Risk [Member] High Yield Risk [Member] Interest Rate Risk [Member] Liquidity Risk [Member] Management Risk [Member] Market and Economic Risk [Member] Prepayment and Extension Risk [Member] Real Estate Risk [Member] Redemption Risk [Member] Risks Affecting Specific Countries or Regions [Member] Risks Affecting Specific Issuers [Member] Small and Mid-Cap Company Risk [Member] U.S. Government Obligations Risk [Member] Thornburg Summit Fund Commodities-Related Investment Risk [Member] Depositary Receipts Risk [Member] Derivatives Risk [Member] Inflation Risk [Member] Structured Products Risk [Member] Zero Coupon Bonds and Stripped Securities Risk [Member] Thornburg Investment Income Builder Fund - Class A Thornburg Investment Income Builder Fund - Class C Thornburg Investment Income Builder Fund - Class I Thornburg Investment Income Builder Fund - Class R6 Thornburg Summit Fund - Class A Thornburg Summit Fund - Class I MSCI World Net Total Return USD Index (reflects no deduction for fees, expenses, or U.S. taxes) Bloomberg U.S. Aggregate Total Return Index Value USD (reflects no deduction for fees, expenses, or taxes) Blended Index (reflects no deduction for fees, expenses, or U.S. taxes) MSCI All Country World Net Total Return USD Index (reflects no deduction for fees, expenses, or taxes) Bloomberg Global-Aggregate Total Return Index Value Unhedged USD (reflects no deduction for fees, expenses, or taxes) Blended Index (reflects no deduction for fees, expenses, or U.S. taxes) [Member] Thornburg New Mexico Intermediate Municipal Fund Thornburg New Mexico Intermediate Municipal Fund - Class A Thornburg New Mexico Intermediate Municipal Fund - Class D Thornburg New Mexico Intermediate Municipal Fund - Class I Thornburg New York Intermediate Municipal Fund Thornburg New York Intermediate Municipal Fund - Class A Thornburg New York Intermediate Municipal Fund - Class I Thornburg International Equity Fund Thornburg International Equity Fund - Class A Thornburg International Equity Fund - Class C Thornburg International Equity Fund - Class I Thornburg Investment Income Builder Fund Thornburg Investment Income Builder Fund - Class A Thornburg Investment Income Builder Fund - Class C Thornburg Investment Income Builder Fund - Class I Thornburg Global Opportunities Fund Thornburg Global Opportunities Fund - Class A Thornburg Global Opportunities Fund - Class C Thornburg Global Opportunities Fund - Class I Thornburg International Growth Fund Thornburg International Growth Fund - Class I Thornburg International Growth Fund - Class A Thornburg International Growth Fund - Class C Thornburg Strategic Income Fund Thornburg Strategic Income Fund - Class A Thornburg Strategic Income Fund - Class C Thornburg Strategic Income Fund - Class I Thornburg Strategic Municipal Income Fund Thornburg Strategic Municipal Income Fund Class A Thornburg Strategic Municipal Income Fund Class C Thornburg Strategic Municipal Income Fund Class I Thornburg Developing World Fund Thornburg Developing World Fund Class A Thornburg Developing World Fund Class C Thornburg Developing World Fund Class I Thornburg Better World International Fund Thornburg Better World International Fund - Class A Thornburg Better World International Fund - Class C Thornburg Better World International Fund - Class I Thornburg Summit Fund Thornburg Summit Fund - Class I Thornburg International Equity Fund - Class R5 Thornburg International Equity Fund - Class R4 Thornburg International Equity Fund - Class R3 Thornburg International Equity Fund - Class R6 Thornburg Investment Income Builder Fund - Class R3 Thornburg Investment Income Builder Fund - Class R5 Thornburg Investment Income Builder Fund - Class R4 Thornburg Investment Income Builder Fund - Class R6 Thornburg Global Opportunities Fund - Class R3 Thornburg Global Opportunities Fund - Class R4 Thornburg Global Opportunities Fund - Class R5 Thornburg Global Opportunities Fund - Class R6 Thornburg International Growth Fund - Class R3 Thornburg International Growth Fund - Class R4 Thornburg International Growth Fund - Class R5 Thornburg International Growth Fund - Class R6 Thornburg Strategic Income Fund - Class R3 Thornburg Strategic Income Fund - Class R5 Thornburg Strategic Income Fund - Class R4 Thornburg Strategic Income Fund - Class R6 Thornburg Developing World Fund Class R5 Thornburg Developing World Fund Class R6 Retirement Thornburg Limited Term U.S. Government Fund Thornburg Limited Term U.S. Government Fund - Class R3 Thornburg Limited Term U.S. Government Fund - Class R4 Thornburg Limited Term U.S. Government Fund - Class R5 Thornburg Limited Term Income Fund Thornburg Limited Term Income Fund - Class R3 Thornburg Limited Term Income Fund - Class R4 Thornburg Limited Term Income Fund - Class R5 Thornburg Limited Term Income Fund - Class R6 Blended Index (reflects no deduction for fees, expenses, or U.S. taxes) MSCI Emerging Markets Net Total Return USD Index Thornburg Summit Fund - Class A Thornburg Limited Term Municipal Fund - Class A Thornburg Limited Term Municipal Fund - Class C Thornburg Limited Term Municipal Fund - Class I Thornburg California Limited Term Municipal Fund - Class A Thornburg California Limited Term Municipal Fund - Class C Thornburg California Limited Term Municipal Fund - Class I Thornburg Limited Term U.S. Government Fund - Class A Thornburg Limited Term U.S. Government Fund - Class C Thornburg Limited Term U.S. Government Fund - Class I Thornburg Intermediate Municipal Fund - Class A Thornburg Intermediate Municipal Fund - Class C Thornburg Intermediate Municipal Fund - Class I Thornburg Limited Term Income Fund - Class A Thornburg Limited Term Income Fund - Class C Thornburg Limited Term Income Fund - Class I Thornburg Short Duration Municipal Fund Class A Thornburg Short Duration Municipal Fund Class I Thornburg Ultra Short Income Fund Class A Thornburg Ultra Short Income Fund Class I Thornburg Limited Term Municipal Fund - Class C2 Thornburg California Limited Term Municipal Fund - Class C2 Thornburg Limited Term U.S. Government Fund - Class C2 Thornburg Intermediate Municipal Fund - Class C2 Thornburg Limited Term Income Fund - Class C2 Thornburg Limited Term Municipal Fund Thornburg California Limited Term Municipal Fund Thornburg Intermediate Municipal Fund Thornburg Short Duration Municipal Fund Thornburg Ultra Short Income Fund ICE BofA 1-10 Year U.S. Municipal Securities Index (reflects no deduction for fees, expenses, or taxes) Thornburg Core Plus Bond Fund Thornburg Core Plus Bond Fund - Class A Thornburg Core Plus Bond Fund - Class C Thornburg Core Plus Bond Fund - Class I Thornburg Core Plus Bond Fund - Class R6 Managed Funds Thornburg Emerging Markets Managed Account Fund Thornburg Emerging Markets Managed Account Fund - Class SMA Thornburg Municipal Managed Account Fund Thornburg Municipal Managed Account Fund - Class SMA Cybersecurity and Operational Risk. Emerging Markets Risk. Equity Risk. Foreign Currency Risk. Foreign Investment Risk. Liquidity Risk. Management Risk. Market and Economic Risk. Redemption Risk. Risks Affecting Specific Countries or Regions. Risks Affecting Specific Issuers. Small and Mid-Cap Company Risk. High Yield Risk. Tax Risk. Developing Country Risk. Real Estate Risk. ESG Investing Risk. Information Technology Securities Risk. Prepayment and Extension Risk. Commodities-Related Investment Risk. Derivatives Risk. Inflation Risk. Structured Products Risk. Single State Risk. MSCI World Net Total Return USD Index (reflects no deduction for fees, expenses, or U.S. taxes) Bloomberg U.S. Aggregate Total Return Index Value USD (reflects no deduction for fees, expenses, or taxes) Bloomberg Global-Aggregate Total Return Index Value Unhedged USD (reflects no deduction for fees, expenses, or taxes) ICE BofA U.S. Municipal Securities Index (reflects no deduction for fees, expenses, or taxes) MSCI All Country World ex-U.S. Index (reflects no deduction for fees, expenses, or U.S. taxes) MSCI All Country World ex USA Net Total Return (reflects no deduction for fees, expenses, or U.S. taxes) MSCI All Country World ex U.S. Growth Net Total Return USD Index (reflects no deduction for fees, expenses, or U.S. taxes) MSCI All Country World Net Total Return USD Index (reflects no deduction for fees, expenses, or taxes) U.S. Government Obligations Risk. Zero Coupon Bonds and Stripped Securities Risk. Foreign Government Obligations Risk. Depositary Receipts Risk. Growth Company Risk. Convertible Debt Obligation Risk. Thornburg High Income Bond Managed Account Fund Thornburg Investment Grade Bond Managed Account Fund Thornburg High Income Bond Managed Account Fund - Class SMA Thornburg Investment Grade Bond Managed Account Fund - Class SMA MSCI All Country World ex USA Net Total Return USD Index (reflects no deduction for fees, expenses, or U.S. taxes). MSCI All Country World ex USA Growth Net Total Return USD Index (reflects no deduction for fees, expenses, or U.S. taxes). Bloomberg U.S. Government Intermediate Total Return Index Value Unhedged (reflects no deduction for fees, expenses, or taxes) Bloomberg Intermediate U.S. Government/Credit Total Return Index Value Unhedged (reflects no deduction for fees, expenses, or taxes) Bloomberg U.S. Universal Total Return Index Value Unhedged (reflects no deduction for fees, expenses, or taxes) ICE BofA U.S. Treasury Bill Index (reflects no deduction for fees, expenses, or taxes). ICE BofA 1-3 Year U.S. Municipal Securities Index (reflects no deduction for fees, expenses, or taxes). ICE BofA 3-15 Year U.S. Municipal Securities Index (reflects no deduction for fees, expenses, or taxes). Blended Index (reflects no deduction for fees, expenses, or U.S. taxes). Bank Loans Risk. Foreign Government Obligations Risks. Market Capitalization Risk. Risks Affecting Mortgage-Backed Securities and Asset-Backed Securities.