v3.25.3
Label Element Value
Western Asset SMASh Series Core Completion Fund | Mortgage-Backed Securities [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 40.20%
Western Asset SMASh Series Core Completion Fund | Asset-Backed Securities [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 20.20%
Western Asset SMASh Series Core Completion Fund | Collateralized Mortgage Obligations [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 17.90%
Western Asset SMASh Series Core Completion Fund | U.S. Government & Agency Obligations [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 6.40%
Western Asset SMASh Series Core Completion Fund | Sovereign Bonds [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 3.40%
Western Asset SMASh Series Core Completion Fund | Energy [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 3.00%
Western Asset SMASh Series Core Completion Fund | Communication Services [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 1.60%
Western Asset SMASh Series Core Completion Fund | Materials [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 1.40%
Western Asset SMASh Series Core Completion Fund | Financials [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 1.20%
Western Asset SMASh Series Core Completion Fund | Consumer Discretionary [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 0.90%
Western Asset SMASh Series Core Completion Fund | U.S. Treasury Inflation Protected Securities [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 0.90%
Western Asset SMASh Series Core Completion Fund | Health Care [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 0.60%
Western Asset SMASh Series Core Completion Fund | Consumer Staples [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 0.60%
Western Asset SMASh Series Core Completion Fund | Industrials [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 0.40%
Western Asset SMASh Series Core Completion Fund | Purchased Options [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 0.20%
Western Asset SMASh Series Core Completion Fund | Information Technology [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 0.20%
Western Asset SMASh Series Core Completion Fund | Utilities [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 0.20%
Western Asset SMASh Series Core Completion Fund | Short-Term Investments [Member]  
Holdings [Line Items] oef_HoldingsLineItems  
Percent of Total Investments oef_PctOfTotalInv 0.70%