| **Average Annual Total Returns - FidelityInfrastructureFund-PRO - FidelityInfrastructureFund-PRO - Fidelity Infrastructure Fund** | Dec. 30, 2024 |
|-----------------------------------------------------------------------------------------------------------------------------------|---------------|
| Fidelity Infrastructure Fund | Return Before Taxes                                                                                |          |  |
| **Average Annual Return:**                                                                                                        |          |  |
| Past 1 year                                                                                                                       | 8.44%         |  |
| Since Inception                                                                                                                   | 6.18%         | [1] |
| Fidelity Infrastructure Fund | After Taxes on Distributions                                                                       |          |  |
| **Average Annual Return:**                                                                                                        |          |  |
| Past 1 year                                                                                                                       | 7.94%         |  |
| Since Inception                                                                                                                   | 5.90%         | [1] |
| Fidelity Infrastructure Fund | After Taxes on Distributions and Sales                                                             |          |  |
| **Average Annual Return:**                                                                                                        |          |  |
| Past 1 year                                                                                                                       | 5.32%         |  |
| Since Inception                                                                                                                   | 4.83%         | [1] |
| MS159                                                                                                                             |          |  |
| **Average Annual Return:**                                                                                                        |          |  |
| Past 1 year                                                                                                                       | 22.65%        |  |
| Since Inception                                                                                                                   | 9.53%         |  |
| SP212                                                                                                                             |          |  |
| **Average Annual Return:**                                                                                                        |          |  |
| Past 1 year                                                                                                                       | 6.79%         |  |
| Since Inception                                                                                                                   | 3.75%         |  |
|                                                                                                                                   |
| [1]AFrom November 5, 2019.                                                                                                        |

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