| **Expense Example, No Redemption - FidelityInternationalSmallCapFund-AMCIZPRO - FidelityInternationalSmallCapFund-AMCIZPRO - Fidelity International Small Cap Fund** | Dec. 30, 2023 USD ($) |
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| Fidelity Advisor International Small Cap Fund - Class A                                                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                                                                  |                  |
| 1 Year                                                                                                                                                               | $ 712                 |
| 3 Years                                                                                                                                                              | 1,001                 |
| 5 Years                                                                                                                                                              | 1,312                 |
| 10 Years                                                                                                                                                             | 2,190                 |
| Fidelity Advisor International Small Cap Fund - Class C                                                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                                                                  |                  |
| 1 Year                                                                                                                                                               | 222                   |
| 3 Years                                                                                                                                                              | 685                   |
| 5 Years                                                                                                                                                              | 1,175                 |
| 10 Years                                                                                                                                                             | 2,331                 |
| Fidelity Advisor International Small Cap Fund - Class M                                                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                                                                  |                  |
| 1 Year                                                                                                                                                               | 516                   |
| 3 Years                                                                                                                                                              | 864                   |
| 5 Years                                                                                                                                                              | 1,236                 |
| 10 Years                                                                                                                                                             | 2,278                 |
| Fidelity Advisor International Small Cap Fund - Class I                                                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                                                                  |                  |
| 1 Year                                                                                                                                                               | 118                   |
| 3 Years                                                                                                                                                              | 368                   |
| 5 Years                                                                                                                                                              | 638                   |
| 10 Years                                                                                                                                                             | 1,409                 |
| Fidelity Advisor International Small Cap Fund - Class Z                                                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                                                                  |                  |
| 1 Year                                                                                                                                                               | 105                   |
| 3 Years                                                                                                                                                              | 328                   |
| 5 Years                                                                                                                                                              | 569                   |
| 10 Years                                                                                                                                                             | $ 1,259               |

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| - 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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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
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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
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection example -Paragraph 2 -Subparagraph 1
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 4 -Subparagraph f
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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
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Subsection instructions -Paragraph 4 -Subparagraph f
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