| Label | Element | Value |
|---|---|---|
| Liquid Reserves Portfolio | Repurchase Agreements [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Total Investments | oef_PctOfTotalInv | 43.30% |
| Liquid Reserves Portfolio | Commercial Paper [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Total Investments | oef_PctOfTotalInv | 32.30% |
| Liquid Reserves Portfolio | Time Deposits [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Total Investments | oef_PctOfTotalInv | 16.40% |
| Liquid Reserves Portfolio | Certificates of Deposit [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Total Investments | oef_PctOfTotalInv | 6.70% |
| Liquid Reserves Portfolio | U.S. Treasury Bills [Member] | ||
| Holdings [Line Items] | oef_HoldingsLineItems | |
| Percent of Total Investments | oef_PctOfTotalInv | 1.30% |