Risk/Return Summary - FidelityEnvironmentandAlternativeEnergyNaturalResourcesFunds-ComboPRO - FidelityEnvironmentandAlternativeEnergyNaturalResourcesFunds-ComboPRO - Fidelity Environment and Alternative Energy Fund	Apr. 29, 2025
Risk Nondiversified Status [Text]
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Risk Text Block	In addition, the fund is classified as non-diversified under the Investment Company Act of 1940 (1940 Act), which means that it has the ability to invest a greater portion of assets in securities of a smaller number of individual issuers than a diversified fund. As a result, changes in the market value of a single investment could cause greater fluctuations in share price than would occur in a more diversified fund.
Risk Lose Money [Text]
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Risk Text Block	You could lose money by investing in the fund.
Risk Not Insured Depository Institution [Text]
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Risk Text Block	An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency .
SustainabilityRiskMember
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Risk Text Block	Sustainability Risk. Application of Fidelity Management & Research Company LLC's (FMR) (the Adviser) environmental, social and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance depending on whether certain investments are in or out of favor. The criteria related to the fund's ESG ratings process and/or adherence to its sustainable investing exclusion criteria may result in the fund forgoing opportunities to buy certain securities when it might otherwise be advantageous to do so, or selling securities for ESG reasons when it might be otherwise disadvantageous for it to do so. As a result, the fund's performance may at times be better or worse than the performance of funds that do not use ESG or sustainability criteria. There are significant differences in interpretations of what it means for an issuer to have positive ESG factors. While the Adviser believes its definitions are reasonable, the portfolio decisions it makes may differ with other investors' or advisers' views. When evaluating an issuer, the Adviser is dependent on information or data obtained through voluntary or third-party reporting that may be incomplete, inaccurate, or unavailable, which could cause the Adviser to incorrectly assess an issuer's business practices.
EnvironmentAndAlternativeEnergyIndustryConcentrationMember
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Risk Text Block	Environment and Alternative Energy Industry Concentration. The environment and alternative energy industries can be significantly affected by government regulations and subsidies, changing supply and demand for traditional energy sources, and availability of funding for remedial cleanup or development of new technologies, and can be subject to risks associated with hazardous materials.
IssuerSpecificChangesMember
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Risk Text Block	Issuer-Specific Changes. The value of an individual security or particular type of security can be more volatile than, and can perform differently from, the market as a whole. The value of securities of smaller issuers can be more volatile than that of larger issuers.
StockMarketVolatilityMember
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Risk Text Block	Stock Market Volatility. Stock markets are volatile and can decline significantly in response to adverse issuer, political, regulatory, market, or economic developments. Different parts of the market, including different market sectors, and different types of securities can react differently to these developments.
ForeignExposureMember
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Risk Text Block	Foreign Exposure. Foreign markets can be more volatile than the U.S. market due to increased risks of adverse issuer, political, regulatory, market, or economic developments and can perform differently from the U.S. market.