Expense Example, No Redemption - FidelitySustainableTargetDateFunds-ComboClassAMCIZPro - FidelitySustainableTargetDateFunds-ComboClassAMCIZPro - Fidelity Sustainable Target Date 2020 Fund	May 30, 2024 USD ($)
Fidelity Advisor Sustainable Target Date 2020 Fund - Class Z
Expense Example, No Redemption:
1 Year	$ 34
3 Years	106
5 Years	185
10 Years	418
Fidelity Advisor Sustainable Target Date 2020 Fund - Class C
Expense Example, No Redemption:
1 Year	146
3 Years	452
5 Years	782
10 Years	1,509
Fidelity Advisor Sustainable Target Date 2020 Fund - Class M
Expense Example, No Redemption:
1 Year	442
3 Years	636
5 Years	847
10 Years	1,453
Fidelity Advisor Sustainable Target Date 2020 Fund - Class A
Expense Example, No Redemption:
1 Year	640
3 Years	780
5 Years	932
10 Years	1,373
Fidelity Advisor Sustainable Target Date 2020 Fund - Class I
Expense Example, No Redemption:
1 Year	44
3 Years	138
5 Years	241
10 Years	$ 542

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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

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-Publisher SEC
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-Section 3
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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