v3.26.1
Shareholder Report, Average Annual Return (Details) 74200007300_Franklin Oregon Tax-Free Income Fund_Class A_TSR Annual {Class A}
12 Months Ended 60 Months Ended 120 Months Ended
Feb. 28, 2026
Feb. 28, 2026
Feb. 28, 2026
Class A      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Class A (with sales charge)    
Average Annual Return, Percent 0.18% (0.04%) 1.32%
Without Sales Load [Member] | Class A      
Average Annual Return [Line Items]      
Line Graph and Table Measure Name Class A    
Average Annual Return, Percent 4.08% 0.73% 1.70%
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%