| **Expense Example, No Redemption - FidelityInternationalSmallCapFund-AMCIZPRO - FidelityInternationalSmallCapFund-AMCIZPRO - Fidelity International Small Cap Fund** | Dec. 30, 2024 USD ($) |
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| Fidelity Advisor International Small Cap Fund - Class A                                                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                                                                  |                  |
| 1 Year                                                                                                                                                               | $ 699                 |
| 3 Years                                                                                                                                                              | 960                   |
| 5 Years                                                                                                                                                              | 1,242                 |
| 10 Years                                                                                                                                                             | 2,042                 |
| Fidelity Advisor International Small Cap Fund - Class C                                                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                                                                  |                  |
| 1 Year                                                                                                                                                               | 207                   |
| 3 Years                                                                                                                                                              | 640                   |
| 5 Years                                                                                                                                                              | 1,098                 |
| 10 Years                                                                                                                                                             | 2,176                 |
| Fidelity Advisor International Small Cap Fund - Class M                                                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                                                                  |                  |
| 1 Year                                                                                                                                                               | 501                   |
| 3 Years                                                                                                                                                              | 819                   |
| 5 Years                                                                                                                                                              | 1,160                 |
| 10 Years                                                                                                                                                             | 2,120                 |
| Fidelity Advisor International Small Cap Fund - Class I                                                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                                                                  |                  |
| 1 Year                                                                                                                                                               | 106                   |
| 3 Years                                                                                                                                                              | 331                   |
| 5 Years                                                                                                                                                              | 574                   |
| 10 Years                                                                                                                                                             | 1,271                 |
| Fidelity Advisor International Small Cap Fund - Class Z                                                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                                                                  |                  |
| 1 Year                                                                                                                                                               | 94                    |
| 3 Years                                                                                                                                                              | 293                   |
| 5 Years                                                                                                                                                              | 509                   |
| 10 Years                                                                                                                                                             | $ 1,131               |

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| - References
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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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| - Definition
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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| - Definition
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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| - Definition
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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