| **Average Annual Total Returns - BroadlyDiversifiedInternationalEquityFunds-RetailComboPRO - BroadlyDiversifiedInternationalEquityFunds-RetailComboPRO - Fidelity Diversified International Fund** | Dec. 30, 2024 |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|
| Fidelity Diversified International Fund | Return Before Taxes                                                                                                                                      |          |
| **Average Annual Return:**                                                                                                                                                                         |          |
| Past 1 year                                                                                                                                                                                        | 17.71%        |
| Past 5 years                                                                                                                                                                                       | 9.30%         |
| Past 10 years                                                                                                                                                                                      | 4.87%         |
| Fidelity Diversified International Fund | After Taxes on Distributions                                                                                                                             |          |
| **Average Annual Return:**                                                                                                                                                                         |          |
| Past 1 year                                                                                                                                                                                        | 16.67%        |
| Past 5 years                                                                                                                                                                                       | 8.52%         |
| Past 10 years                                                                                                                                                                                      | 4.10%         |
| Fidelity Diversified International Fund | After Taxes on Distributions and Sales                                                                                                                   |          |
| **Average Annual Return:**                                                                                                                                                                         |          |
| Past 1 year                                                                                                                                                                                        | 11.43%        |
| Past 5 years                                                                                                                                                                                       | 7.52%         |
| Past 10 years                                                                                                                                                                                      | 3.89%         |
| MS001                                                                                                                                                                                              |          |
| **Average Annual Return:**                                                                                                                                                                         |          |
| Past 1 year                                                                                                                                                                                        | 18.49%        |
| Past 5 years                                                                                                                                                                                       | 8.39%         |
| Past 10 years                                                                                                                                                                                      | 4.48%         |

| X                                                                                                                                                                                           |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - References
No definition available.
+ Details**Name:**rr_AverageAnnualReturnAbstract**Namespace Prefix:**rr_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Return Before Taxes.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form N-1A -Section 4 -Subsection b -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2
+ Details**Name:**rr_AverageAnnualReturnYear01**Namespace Prefix:**rr_**Data Type:**xbrli:pureItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Return Before Taxes.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form N-1A -Section 4 -Subsection b -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2
+ Details**Name:**rr_AverageAnnualReturnYear05**Namespace Prefix:**rr_**Data Type:**xbrli:pureItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Return Before Taxes.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form N-1A -Section 4 -Subsection b -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2
+ Details**Name:**rr_AverageAnnualReturnYear10**Namespace Prefix:**rr_**Data Type:**xbrli:pureItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**dei_DocumentInformationDocumentAxis=fmr_BroadlyDiversifiedInternationalEquityFunds-RetailComboPROMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**dei_LegalEntityAxis=fmr_S000007109Member**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                        |
|------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**rr_ProspectusShareClassAxis=fmr_C000019438Member**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                             |
|-----------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**rr_PerformanceMeasureAxis=fmr_ReturnBeforeTaxesMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**rr_PerformanceMeasureAxis=rr_AfterTaxesOnDistributionsMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**rr_PerformanceMeasureAxis=rr_AfterTaxesOnDistributionsAndSalesMember**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |
| X                                                                                                                                      |
|----------------------------------------------------------------------------------------------------------------------------------------|
| - Details**Name:**rr_PerformanceMeasureAxis=fmr_IndexMS001Member**Namespace Prefix:****Data Type:**na**Balance Type:****Period Type:** |