Shareholder Report, Average Annual Return (Details) 74200006200_Franklin Federal Intermediate-Term Tax-Free Income Fund_Advisor Class_TSR Annual {Advisor Class} |
12 Months Ended | 60 Months Ended | 120 Months Ended |
|---|---|---|---|
Feb. 28, 2026 |
Feb. 28, 2026 |
Feb. 28, 2026 |
|
| Advisor Class | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Advisor Class | ||
| Average Annual Return, Percent | 5.62% | 1.76% | 1.96% |
| Bloomberg Municipal Bond Index [Member] | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Bloomberg Municipal Bond Index | ||
| Average Annual Return, Percent | 4.96% | 1.44% | 2.43% |
| Bloomberg Municipal -5 Year Index [Member] | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Bloomberg Municipal 1-15 Year Index | ||
| Average Annual Return, Percent | 5.61% | 1.74% | 2.34% |