Shareholder Report, Holdings (Details) - Fidelity Commodity Strategy Central Fund |
Jul. 31, 2026 |
|---|---|
| MSIndustrialMetalsSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 25.70% |
| MSPreciousMetalsSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 12.60% |
| MSLivestockSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.10% |
| Agricultural Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 25.30% |
| Energy Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 32.30% |
| DEFuturesContractsMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 48.70% |
| DESwapsMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 64.80% |
| AASwapsMember | |
| Holdings [Line Items] | |
| Percent of Net Long Exposure | 30.40% |
| AAFuturesContractsMember | |
| Holdings [Line Items] | |
| Percent of Net Long Exposure | 22.90% |
| AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember | |
| Holdings [Line Items] | |
| Percent of Net Long Exposure | 46.70% |