| **Expense Example - FidelityWorldwideFund-AMCIZPRO - FidelityWorldwideFund-AMCIZPRO - Fidelity Worldwide Fund** | Dec. 30, 2024 USD ($) |
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| Fidelity Advisor Worldwide Fund - Class A                                                                       |                  |
| **Expense Example:**                                                                                            |                  |
| 1 year                                                                                                          | $ 669                 |
| 3 years                                                                                                         | 869                   |
| 5 years                                                                                                         | 1,086                 |
| 10 years                                                                                                        | 1,707                 |
| Fidelity Advisor Worldwide Fund - Class C                                                                       |                  |
| **Expense Example:**                                                                                            |                  |
| 1 year                                                                                                          | 276                   |
| 3 years                                                                                                         | 545                   |
| 5 years                                                                                                         | 939                   |
| 10 years                                                                                                        | 1,842                 |
| Fidelity Advisor Worldwide Fund - Class M                                                                       |                  |
| **Expense Example:**                                                                                            |                  |
| 1 year                                                                                                          | 471                   |
| 3 years                                                                                                         | 727                   |
| 5 years                                                                                                         | 1,002                 |
| 10 years                                                                                                        | 1,787                 |
| Fidelity Advisor Worldwide Fund - Class I                                                                       |                  |
| **Expense Example:**                                                                                            |                  |
| 1 year                                                                                                          | 74                    |
| 3 years                                                                                                         | 230                   |
| 5 years                                                                                                         | 401                   |
| 10 years                                                                                                        | 894                   |
| Fidelity Advisor Worldwide Fund - Class Z                                                                       |                  |
| **Expense Example:**                                                                                            |                  |
| 1 year                                                                                                          | 62                    |
| 3 years                                                                                                         | 195                   |
| 5 years                                                                                                         | 340                   |
| 10 years                                                                                                        | $ 762                 |

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| - References
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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
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
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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 N-1A -Section 3 -Subsection example -Paragraph 1 -Subparagraph 2
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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
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