Risk/Return Summary - FidelityNASDAQCompositeIndexETF-PRO - FidelityNASDAQCompositeIndexETF-PRO - Fidelity Nasdaq Composite Index ETF	Jan. 29, 2025
Risk Nondiversified Status [Text]
Prospectus Line Items
Risk Text Block	In addition, the fund may operate as a non-diversified fund under the 1940 Act to the approximate extent the index is non-diversified. A non-diversified fund may invest a greater portion of its 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]
Prospectus Line Items
Risk Text Block	You could lose money by investing in the fund.
Risk Not Insured Depository Institution [Text]
Prospectus Line Items
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 .
TechnologyIndustryConcentrationMember
Prospectus Line Items
Risk Text Block	Technology Industry Concentration. The technology industries can be significantly affected by obsolescence of existing technology, short product cycles, falling prices and profits, competition from new market entrants, and general economic conditions.
FluctuationOfNetAssetValueAndSharePriceMember
Prospectus Line Items
Risk Text Block	Fluctuation of Net Asset Value and Share Price. The net asset value per share (NAV) of the fund will generally fluctuate with changes in the market value of the fund's holdings. The fund's shares can be bought and sold in the secondary market at market prices. Disruptions to creations and redemptions, the existence of extreme market volatility or potential lack of an active trading market for the fund's shares may result in the fund's shares trading significantly above (at a premium) or below (at a discount) to NAV. In addition, in stressed market conditions or periods of market disruption or volatility, the market for shares may become less liquid in response to deteriorating liquidity in the markets for the fund's underlying portfolio holdings.
IssuerSpecificChangesMember
Prospectus Line Items
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. Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty. The value of securities of smaller issuers can be more volatile than that of larger issuers.
StockMarketVolatilityMember
Prospectus Line Items
Risk Text Block	Stock Market Volatility. Stock markets and, as a result, stock market indexes, 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.
SmallCapInvestingMember
Prospectus Line Items
Risk Text Block	Small Cap Investing. The value of securities of smaller, less well-known issuers can perform differently from the market as a whole and other types of stocks and can be more volatile than that of larger issuers.
CorrelationToIndexMember
Prospectus Line Items
Risk Text Block	Correlation to Index. The performance of the fund and its underlying index may vary somewhat due to factors such as fees and expenses of the fund, transaction costs, sample selection, regulatory restrictions, and timing differences associated with additions to and deletions from the index. Errors in the construction or calculation of the index may occur from time to time and may not be identified and corrected for some period of time, which may have an adverse impact on the fund and its shareholders.
SecuritiesLendingRiskMember
Prospectus Line Items
Risk Text Block	Securities Lending Risk. Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.
TradingIssuesMember
Prospectus Line Items
Risk Text Block	Trading Issues. There can be no assurance that an active trading market will be maintained. Market makers and Authorized Participants are not obligated to make a market in the fund's shares or to submit purchase and redemption orders for creation units. Decisions by market makers or Authorized Participants to reduce their role with respect to market making or creation and redemption activities during times of market stress, or a decline in the number of Authorized Participants due to decisions to exit the business, bankruptcy, or other factors, could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying value of the fund's portfolio securities and the market price of fund shares. In addition, trading may be halted, for example, due to market conditions.
PassiveManagementRiskMember
Prospectus Line Items
Risk Text Block	Passive Management Risk. The fund is managed with a passive investment strategy, attempting to track the performance of an unmanaged index of securities, regardless of the current or projected performance of the fund's index or of the actual securities included in the index. This differs from an actively managed fund, which typically seeks to outperform a benchmark index. As a result, the fund's performance could be lower than actively managed funds that may shift their portfolio assets to take advantage of market opportunities or lessen the impact of a market decline or a decline in the value of one or more issuers. The fund may be concentrated to approximately the same extent that the fund's index concentrates in the securities of issuers in a particular industry or group of industries.
MidCapInvestingMember
Prospectus Line Items
Risk Text Block	Mid Cap Investing. The value of securities of medium size, less well-known issuers can perform differently from the market as a whole and other types of stocks and can be more volatile than that of larger issuers.

Risk/Return Summary - FidelityNASDAQCompositeIndexETF-PRO - FidelityNASDAQCompositeIndexETF-PRO - Fidelity Nasdaq Composite Index ETF

Jan. 29, 2025

In addition, the fund may operate as a non-diversified fund under the 1940 Act to the approximate extent the index is non-diversified. A non-diversified fund may invest a greater portion of its 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.

Prospectus Line Items

Risk Text Block

You could lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

Prospectus Line Items

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 .

TechnologyIndustryConcentrationMember

Prospectus Line Items

Risk Text Block

Technology Industry Concentration. The technology industries can be significantly affected by obsolescence of existing technology, short product cycles, falling prices and profits, competition from new market entrants, and general economic conditions.

FluctuationOfNetAssetValueAndSharePriceMember

Prospectus Line Items

Risk Text Block

Fluctuation of Net Asset Value and Share Price. The net asset value per share (NAV) of the fund will generally fluctuate with changes in the market value of the fund's holdings. The fund's shares can be bought and sold in the secondary market at market prices. Disruptions to creations and redemptions, the existence of extreme market volatility or potential lack of an active trading market for the fund's shares may result in the fund's shares trading significantly above (at a premium) or below (at a discount) to NAV. In addition, in stressed market conditions or periods of market disruption or volatility, the market for shares may become less liquid in response to deteriorating liquidity in the markets for the fund's underlying portfolio holdings.

IssuerSpecificChangesMember

Prospectus Line Items

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. Changes in the financial condition of an issuer or counterparty (e.g., broker-dealer or other borrower in a securities lending transaction) can increase the risk of default by an issuer or counterparty, which can affect a security's or instrument's value or result in delays in recovering securities and/or capital from a counterparty. The value of securities of smaller issuers can be more volatile than that of larger issuers.

StockMarketVolatilityMember

Prospectus Line Items

Risk Text Block

Stock Market Volatility. Stock markets and, as a result, stock market indexes, 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.

SmallCapInvestingMember

Prospectus Line Items

Risk Text Block

Small Cap Investing. The value of securities of smaller, less well-known issuers can perform differently from the market as a whole and other types of stocks and can be more volatile than that of larger issuers.

CorrelationToIndexMember

Prospectus Line Items

Risk Text Block

Correlation to Index. The performance of the fund and its underlying index may vary somewhat due to factors such as fees and expenses of the fund, transaction costs, sample selection, regulatory restrictions, and timing differences associated with additions to and deletions from the index. Errors in the construction or calculation of the index may occur from time to time and may not be identified and corrected for some period of time, which may have an adverse impact on the fund and its shareholders.

SecuritiesLendingRiskMember

Prospectus Line Items

Risk Text Block

Securities Lending Risk. Securities lending involves the risk that the borrower may fail to return the securities loaned in a timely manner or at all. If the borrower defaults on its obligation to return the securities loaned because of insolvency or other reasons, a fund could experience delays and costs in recovering the securities loaned or in gaining access to the collateral.

TradingIssuesMember

Prospectus Line Items

Risk Text Block

Trading Issues. There can be no assurance that an active trading market will be maintained. Market makers and Authorized Participants are not obligated to make a market in the fund's shares or to submit purchase and redemption orders for creation units. Decisions by market makers or Authorized Participants to reduce their role with respect to market making or creation and redemption activities during times of market stress, or a decline in the number of Authorized Participants due to decisions to exit the business, bankruptcy, or other factors, could inhibit the effectiveness of the arbitrage process in maintaining the relationship between the underlying value of the fund's portfolio securities and the market price of fund shares. In addition, trading may be halted, for example, due to market conditions.

PassiveManagementRiskMember

Prospectus Line Items

Risk Text Block

Passive Management Risk. The fund is managed with a passive investment strategy, attempting to track the performance of an unmanaged index of securities, regardless of the current or projected performance of the fund's index or of the actual securities included in the index. This differs from an actively managed fund, which typically seeks to outperform a benchmark index. As a result, the fund's performance could be lower than actively managed funds that may shift their portfolio assets to take advantage of market opportunities or lessen the impact of a market decline or a decline in the value of one or more issuers. The fund may be concentrated to approximately the same extent that the fund's index concentrates in the securities of issuers in a particular industry or group of industries.

MidCapInvestingMember

Prospectus Line Items

Risk Text Block

Mid Cap Investing. The value of securities of medium size, less well-known issuers can perform differently from the market as a whole and other types of stocks and can be more volatile than that of larger issuers.