Shareholder Report, Line Graph (Details) - USD ($)	12 Months Ended	84 Months Ended
Shareholder Report, Line Graph (Details) - USD ($)	Jun. 30, 2026	Jun. 30, 2026
C000223010_LG_ClassMember_7YRMember
Account Value [Line Items]
Line Graph and Table Measure Name		<span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® U.S. Equity Central Fund</span>
C000223010_ClassMember_AsOf_2020Member
Account Value [Line Items]
Accumulated Value	$ 10,000
C000223010_ClassMember_AsOf_2021Member
Account Value [Line Items]
Accumulated Value	13,447
C000223010_ClassMember_AsOf_2022Member
Account Value [Line Items]
Accumulated Value	11,332
C000223010_ClassMember_AsOf_2023Member
Account Value [Line Items]
Accumulated Value	13,706
C000223010_ClassMember_AsOf_2024Member
Account Value [Line Items]
Accumulated Value	16,617
C000223010_ClassMember_AsOf_2025Member
Account Value [Line Items]
Accumulated Value	18,969
C000223010_ClassMember_AsOf_2026Member
Account Value [Line Items]
Accumulated Value	25,058
C000223010_LG_1_AdditionalIndexMember_7YRMember
Account Value [Line Items]
Line Graph and Table Measure Name		<span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">MSCI U.S. Investable Market 2500 Index S&P 500 Linked Index (1/1/25)</span>
C000223010_1_AdditionalIndexMember_AsOf_2020Member
Account Value [Line Items]
Accumulated Value	10,000
C000223010_1_AdditionalIndexMember_AsOf_2021Member
Account Value [Line Items]
Accumulated Value	13,399
C000223010_1_AdditionalIndexMember_AsOf_2022Member
Account Value [Line Items]
Accumulated Value	11,554
C000223010_1_AdditionalIndexMember_AsOf_2023Member
Account Value [Line Items]
Accumulated Value	13,777
C000223010_1_AdditionalIndexMember_AsOf_2024Member
Account Value [Line Items]
Accumulated Value	16,979
C000223010_1_AdditionalIndexMember_AsOf_2025Member
Account Value [Line Items]
Accumulated Value	19,650
C000223010_1_AdditionalIndexMember_AsOf_2026Member
Account Value [Line Items]
Accumulated Value	24,037
C000223010_LG_2_AdditionalIndexMember_7YRMember
Account Value [Line Items]
Line Graph and Table Measure Name		<span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">S&P 500® Index</span>
C000223010_2_AdditionalIndexMember_AsOf_2020Member
Account Value [Line Items]
Accumulated Value	10,000
C000223010_2_AdditionalIndexMember_AsOf_2021Member
Account Value [Line Items]
Accumulated Value	13,100
C000223010_2_AdditionalIndexMember_AsOf_2022Member
Account Value [Line Items]
Accumulated Value	11,709
C000223010_2_AdditionalIndexMember_AsOf_2023Member
Account Value [Line Items]
Accumulated Value	14,003
C000223010_2_AdditionalIndexMember_AsOf_2024Member
Account Value [Line Items]
Accumulated Value	17,442
C000223010_2_AdditionalIndexMember_AsOf_2025Member
Account Value [Line Items]
Accumulated Value	20,087
C000223010_2_AdditionalIndexMember_AsOf_2026Member
Account Value [Line Items]
Accumulated Value	$ 24,571