Investment Objectives and Goals - Retail [Member] |
Aug. 20, 2026 |
|---|---|
| Thornburg Investment Income Builder Fund | |
| Prospectus [Line Items] | |
| Risk/Return [Heading] | Investment Income Builder Fund |
| Objective [Heading] | Investment Goal |
| Objective, Primary [Text Block] | The Fund’s primary investment goal is to provide a level of current income which exceeds the average yield on U.S. stocks generally, and which will generally grow, subject to periodic fluctuations, over the years on a per share basis. |
| Objective, Secondary [Text Block] | The Fund’s secondary investment goal is long-term capital appreciation. |
| Thornburg Summit Fund | |
| Prospectus [Line Items] | |
| Risk/Return [Heading] | Summit Fund |
| Objective [Heading] | Investment Goal |
| Objective, Primary [Text Block] | The Fund seeks to grow real wealth over time. |