| **Shareholder Fees - FidelitySeriesSustainableEmergingMarketsSeriesSustainableNon-USDevelopedMarketsFunds-ComboPRO**                                        | Dec. 30, 2023 USD ($) |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------|
| FidelitySeriesSustainableEmergingMarketsSeriesSustainableNon-USDevelopedMarketsFunds-ComboPRO | Fidelity Series Sustainable Non-U.S. Developed Markets Fund |                  |
| **Shareholder Fees:**                                                                                                                                       |                  |
| (fees paid directly from your investment)                                                                                                                   | none                  |

| X                                                                                                                                                                                                                                                                                                                                                                    |
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| - Definition
Other Expenses
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection table -Paragraph 1 -Subparagraph 10
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| - References
No definition available.
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| X                                                                                                                                |
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