Shareholder Report, Average Annual Return (Details) LMF1700_Western Asset Ultra-Short Income Fund_Class I_TSR Annual {Class I} |
12 Months Ended | 60 Months Ended | 120 Months Ended |
|---|---|---|---|
May 31, 2026 |
May 31, 2026 |
May 31, 2026 |
|
| Class I | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Class I | ||
| Average Annual Return, Percent | 5.11% | 3.85% | 3.29% |
| Bloomberg U.S. Aggregate Index | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | Bloomberg U.S. Aggregate Index | ||
| Average Annual Return, Percent | 5.13% | 0.17% | 1.70% |
| ICE BofA 3-Month U.S. Treasury Bill Index | |||
| Average Annual Return [Line Items] | |||
| Line Graph and Table Measure Name | ICE BofA 3-Month U.S. Treasury Bill Index | ||
| Average Annual Return, Percent | 3.88% | 3.46% | 2.32% |