| **Expense Example, No Redemption - FidelityJapanFund-AMCIZPRO - FidelityJapanFund-AMCIZPRO - Fidelity Japan Fund** | Dec. 30, 2024 USD ($) |
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| Fidelity Advisor Japan Fund - Class A                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                |                  |
| 1 Year                                                                                                             | $ 666                 |
| 3 Years                                                                                                            | 860                   |
| 5 Years                                                                                                            | 1,070                 |
| 10 Years                                                                                                           | 1,674                 |
| Fidelity Advisor Japan Fund - Class C                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                |                  |
| 1 Year                                                                                                             | 173                   |
| 3 Years                                                                                                            | 536                   |
| 5 Years                                                                                                            | 923                   |
| 10 Years                                                                                                           | 1,810                 |
| Fidelity Advisor Japan Fund - Class M                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                |                  |
| 1 Year                                                                                                             | 468                   |
| 3 Years                                                                                                            | 718                   |
| 5 Years                                                                                                            | 987                   |
| 10 Years                                                                                                           | 1,754                 |
| Fidelity Advisor Japan Fund - Class I                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                |                  |
| 1 Year                                                                                                             | 73                    |
| 3 Years                                                                                                            | 227                   |
| 5 Years                                                                                                            | 395                   |
| 10 Years                                                                                                           | 883                   |
| Fidelity Advisor Japan Fund - Class Z                                                                              |                  |
| **Expense Example, No Redemption:**                                                                                |                  |
| 1 Year                                                                                                             | 57                    |
| 3 Years                                                                                                            | 179                   |
| 5 Years                                                                                                            | 313                   |
| 10 Years                                                                                                           | $ 701                 |

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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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| - 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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