Expense Example {- Fidelity® SAI Real Estate Index Fund} - 07.31 Fidelity SAI Real Estate Index Fund PRO-08 - Fidelity® SAI Real Estate Index Fund - Fidelity SAI Real Estate Index Fund-Default	Sep. 29, 2020 USD ($)
Expense Example:
1 year	$ 7
3 years	39
5 years	78
10 years	$ 192

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- Definition

The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.

+ References

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

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- Definition

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Subsection example
-Paragraph 1
-Subparagraph 2

+ Details

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- Definition

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Subsection example
-Paragraph 1
-Subparagraph 2

+ Details

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- Definition

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form
-Number N-1A
-Chapter A
-Section 3
-Subsection example
-Paragraph 1
-Subparagraph 2

+ Details

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