Shareholder Report, Holdings (Details) - Fidelity Commodity Strategy Central Fund |
Jan. 31, 2026 |
|---|---|
| MSIndustrialMetalsSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 31.80% |
| MSPreciousMetalsSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 14.90% |
| MSLivestockSectorMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 4.40% |
| Agricultural Sector Member | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 21.90% |
| Energy Sector | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 27.00% |
| DEFuturesContractsMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 68.10% |
| DESwapsMember | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 51.20% |
| AAFuturesContractsMember | |
| Holdings [Line Items] | |
| Percent of Net Long Exposure | 31.00% |
| AASwapsMember | |
| Holdings [Line Items] | |
| Percent of Net Long Exposure | 23.30% |
| AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember | |
| Holdings [Line Items] | |
| Percent of Net Long Exposure | 45.70% |