| **Average Annual Total Returns - FidelityInternationalDiscoveryK6Fund-PRO - FidelityInternationalDiscoveryK6Fund-PRO - Fidelity International Discovery K6 Fund** | Dec. 30, 2023 |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|
| Fidelity International Discovery K6 Fund | Return Before Taxes                                                                                                    |          |  |
| **Average Annual Return:**                                                                                                                                        |          |  |
| Past 1 year                                                                                                                                                       | (24.74%)      |  |
| Since Inception                                                                                                                                                   | 3.68%         | [1] |
| MS001                                                                                                                                                             |          |  |
| **Average Annual Return:**                                                                                                                                        |          |  |
| Past 1 year                                                                                                                                                       | (14.27%)      |  |
| Since Inception                                                                                                                                                   | 3.54%         | [1] |
|                                                                                                                                                                   |
| [1]AFrom June 13, 2019.                                                                                                                                           |

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Return Before Taxes.
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Return Before Taxes.
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