v3.26.1
Shareholder Report, Line Graph (Details) LMF5600_Western Asset Oregon Municipals Fund_Class A_TSR Annual {Class A} - USD ($)
12 Months Ended
Apr. 30, 2025
Apr. 30, 2024
Apr. 30, 2023
Apr. 30, 2022
Apr. 30, 2021
Apr. 30, 2020
Apr. 30, 2019
Apr. 30, 2018
Apr. 30, 2017
Apr. 30, 2016
Apr. 30, 2026
Class A                      
Account Value [Line Items]                      
Line Graph and Table Measure Name                     Class A (with sales charge)
Accumulated Value $ 10,611 $ 10,410 $ 10,275 $ 10,185 $ 10,942 $ 10,185 $ 10,068 $ 9,620 $ 9,455 $ 9,575 $ 11,223
Bloomberg Municipal Bond Index [Member]                      
Account Value [Line Items]                      
Line Graph and Table Measure Name                     Bloomberg Municipal Bond Index
Accumulated Value 11,688 11,497 11,262 10,947 11,884 11,030 10,797 10,170 10,014 10,000 $ 12,429
Bloomberg Oregon Municipal Bond Index [Member]                      
Account Value [Line Items]                      
Line Graph and Table Measure Name                     Bloomberg Oregon Municipal Bond Index
Accumulated Value $ 11,465 $ 11,285 $ 11,164 $ 10,845 $ 11,859 $ 11,154 $ 10,748 $ 10,130 $ 10,022 $ 10,000 $ 12,234