Expense Example, No Redemption - FidelityEquityMarketNeutralFund-AMCIZPro - FidelityEquityMarketNeutralFund-AMCIZPro - Fidelity Equity Market Neutral Fund	Apr. 01, 2025 USD ($)
Fidelity Advisor Equity Market Neutral Fund - Class Z
Expense Example, No Redemption:
1 Year	$ 111
3 Years	681
5 Years	1,345
10 Years	3,125
Fidelity Advisor Equity Market Neutral Fund - Class I
Expense Example, No Redemption:
1 Year	116
3 Years	696
5 Years	1,370
10 Years	3,173
Fidelity Advisor Equity Market Neutral Fund - Class M
Expense Example, No Redemption:
1 Year	511
3 Years	1,167
5 Years	1,909
10 Years	3,862
Fidelity Advisor Equity Market Neutral Fund - Class A
Expense Example, No Redemption:
1 Year	708
3 Years	1,302
5 Years	1,983
10 Years	3,788
Fidelity Advisor Equity Market Neutral Fund - Class C
Expense Example, No Redemption:
1 Year	217
3 Years	994
5 Years	1,855
10 Years	$ 3,918

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You would pay the following expenses if you did not redeem your shares. Include the second 1-, 3-, 5-, and 10-year periods and related narrative explanation only if a sales charge (load) or other fee is charged upon redemption.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 3
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 3
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form N-1A
-Section 3
-Subsection instructions
-Paragraph 4
-Subparagraph f

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