v3.26.3
Investment Risks
Oct. 30, 2026
FidelityShort-TermBondFund-ETFClassPRO | Fidelity Short-Term Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelityShort-TermBondFund-ETFClassPRO | Fidelity Short-Term Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelityShort-TermBondFund-ETFClassPRO | Fidelity Short-Term Bond Fund | LeverageRiskMember  
Prospectus Line Items  
Risk [Text Block] Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.
FidelityShort-TermBondFund-ETFClassPRO | Fidelity Short-Term Bond Fund | 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's ETF Class will generally fluctuate with changes in the market value of the fund's holdings. The fund's ETF Class 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 ETF Class shares may result in the fund's ETF Class shares trading significantly above (at a premium) or below (at a discount) to NAV. Given the nature of the relevant markets for certain of the fund's securities, the fund's ETF Class shares may trade at a larger premium or discount to the NAV than shares of other ETFs. In addition, in stressed market conditions or periods of market disruption or volatility, the market for the fund's ETF Class shares may become less liquid in response to deteriorating liquidity in the markets for the fund's underlying portfolio holdings.
FidelityShort-TermBondFund-ETFClassPRO | Fidelity Short-Term Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
FidelityShort-TermBondFund-ETFClassPRO | Fidelity Short-Term Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
FidelityShort-TermBondFund-ETFClassPRO | Fidelity Short-Term Bond Fund | CashTransactionsRiskMember  
Prospectus Line Items  
Risk [Text Block] Cash Transactions Risk. The fund may effect some or all creations and redemptions of its ETF Class shares using cash rather than in-kind securities. As a result, an investment in the fund may be less tax-efficient than an investment in a fund that effects ETF share class redemptions entirely in-kind.
FidelityShort-TermBondFund-ETFClassPRO | Fidelity Short-Term Bond Fund | 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 ETF Class 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 the fund's ETF Class shares. In addition, trading may be halted, for example, due to market conditions.
FidelityShort-TermBondFund-ETFClassPRO | Fidelity Short-Term Bond Fund | ForeignExposureMember  
Prospectus Line Items  
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.
FidelityShort-TermBondFund-ETFClassPRO | Fidelity Short-Term Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Low Duration Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Low Duration Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Low Duration Bond Fund | LeverageRiskMember  
Prospectus Line Items  
Risk [Text Block] Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Low Duration Bond Fund | FinancialServicesConcentrationMember  
Prospectus Line Items  
Risk [Text Block] Financial Services Concentration. Changes in government regulation and interest rates and economic downturns can have a significant negative effect on issuers in the financial services sector, including the price of their securities or their ability to meet their payment obligations.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Low Duration Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Low Duration Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Low Duration Bond Fund | ForeignExposureMember  
Prospectus Line Items  
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.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Low Duration Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Short-Term Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Short-Term Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Short-Term Bond Fund | LeverageRiskMember  
Prospectus Line Items  
Risk [Text Block] Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Short-Term Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Short-Term Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Short-Term Bond Fund | HighPortfolioTurnoverMember  
Prospectus Line Items  
Risk [Text Block] High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Short-Term Bond Fund | ForeignExposureMember  
Prospectus Line Items  
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.
FidelitySAILowDurationBondFund-ComboPRO | Fidelity SAI Short-Term Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
FidelityIntermediateBondFund-RetailPRO | Fidelity Intermediate Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelityIntermediateBondFund-RetailPRO | Fidelity Intermediate Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelityIntermediateBondFund-RetailPRO | Fidelity Intermediate Bond Fund | LeverageRiskMember  
Prospectus Line Items  
Risk [Text Block] Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.
FidelityIntermediateBondFund-RetailPRO | Fidelity Intermediate Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments.
FidelityIntermediateBondFund-RetailPRO | Fidelity Intermediate Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
FidelityIntermediateBondFund-RetailPRO | Fidelity Intermediate Bond Fund | ForeignExposureMember  
Prospectus Line Items  
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.
FidelityIntermediateBondFund-RetailPRO | Fidelity Intermediate Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
FidelityTacticalBondFund-AMCIZPRO | Fidelity Tactical Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelityTacticalBondFund-AMCIZPRO | Fidelity Tactical Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelityTacticalBondFund-AMCIZPRO | Fidelity Tactical Bond Fund | ForeignAndEmergingMarketsRiskMember  
Prospectus Line Items  
Risk [Text Block] Foreign and Emerging Markets Risk. Foreign markets, particularly emerging 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. The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile. Foreign exchange rates also can be extremely volatile.
FidelityTacticalBondFund-AMCIZPRO | Fidelity Tactical Bond Fund | LeverageRiskMember  
Prospectus Line Items  
Risk [Text Block] Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.
FidelityTacticalBondFund-AMCIZPRO | Fidelity Tactical Bond Fund | ContingentConvertibleSecuritiesRiskMember  
Prospectus Line Items  
Risk [Text Block] Contingent Convertible Securities Risk. Contingent convertible securities have unique equity conversion or principal write-down features that involve additional risks, which may include cancellation of interest payments by the issuer or a regulatory authority; subordination to other creditors due to either a liquidation or other bankruptcy-related event or a conversion of the security from debt to equity; and a write-down of the security's principal amount.
FidelityTacticalBondFund-AMCIZPRO | Fidelity Tactical Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) and certain types of other securities involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities and certain types of other securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments and can be difficult to resell. CLO tranches can experience substantial losses due to actual and anticipated defaults, as well as aversion to CLO securities as a class. Investments in covenant-lite loans carry more risk than traditional loans as they allow issuers to engage in activities that would otherwise be difficult or impossible under a traditional loan agreement. In the event of default, covenant-lite obligations have lower recovery values as the lender may not have the opportunity to negotiate with the borrower prior to default.
FidelityTacticalBondFund-AMCIZPRO | Fidelity Tactical Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
FidelityTacticalBondFund-AMCIZPRO | Fidelity Tactical Bond Fund | ForeignCurrencyTransactionsMember  
Prospectus Line Items  
Risk [Text Block] Foreign Currency Transactions. Although a forward foreign currency exchange contract is used to reduce or hedge a fund's exposure to changes in the value of the currency, suitable hedging transactions may not be available in all circumstances, may not be successful, and may eliminate any chance for the fund to benefit from favorable fluctuations in relevant foreign currencies.
FidelityTacticalBondFund-AMCIZPRO | Fidelity Tactical Bond Fund | FloatingRateLoanLiquidityMember  
Prospectus Line Items  
Risk [Text Block] Floating Rate Loan Liquidity. Floating rate loans generally are subject to restrictions on resale. Floating rate loans sometimes trade infrequently in the secondary market. As a result, valuing a floating rate loan can be more difficult, and buying and selling a floating rate loan at an acceptable price can be more difficult or delayed, including extended trade settlement periods. Difficulty in selling a floating rate loan can result in a loss.
FidelityTacticalBondFund-AMCIZPRO | Fidelity Tactical Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
FidelityTacticalBondFund-AMCIZPRO | Fidelity Tactical Bond Fund | InflationProtectedDebtExposureMember  
Prospectus Line Items  
Risk [Text Block] Inflation-Protected Debt Exposure. Increases in real interest rates can cause the price of inflation-protected debt securities to decrease. Interest payments on inflation-protected debt securities can be unpredictable.
FidelityTacticalBondFund-AMCIZPRO | Fidelity Tactical Bond Fund | ImpairmentOfCollateralMember  
Prospectus Line Items  
Risk [Text Block] Impairment of Collateral. A floating rate loan may not be fully collateralized which may cause the floating rate loan to decline significantly in value.
FidelityFlexConservativeIncomeBondFund-PRO | Fidelity Flex Conservative Income Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelityFlexConservativeIncomeBondFund-PRO | Fidelity Flex Conservative Income Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelityFlexConservativeIncomeBondFund-PRO | Fidelity Flex Conservative Income Bond Fund | FinancialServicesConcentrationMember  
Prospectus Line Items  
Risk [Text Block] Financial Services Concentration. Changes in government regulation and interest rates and economic downturns can have a significant negative effect on issuers in the financial services sector, including the price of their securities or their ability to meet their payment obligations.
FidelityFlexConservativeIncomeBondFund-PRO | Fidelity Flex Conservative Income Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
FidelityFlexConservativeIncomeBondFund-PRO | Fidelity Flex Conservative Income Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt or money market security to decrease.
FidelityFlexConservativeIncomeBondFund-PRO | Fidelity Flex Conservative Income Bond Fund | ForeignExposureMember  
Prospectus Line Items  
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.
FidelityFlexConservativeIncomeBondFund-PRO | Fidelity Flex Conservative Income Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
FidelityInvestmentGradeBondFund-AMCIZPRO | Fidelity Investment Grade Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelityInvestmentGradeBondFund-AMCIZPRO | Fidelity Investment Grade Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelityInvestmentGradeBondFund-AMCIZPRO | Fidelity Investment Grade Bond Fund | LeverageRiskMember  
Prospectus Line Items  
Risk [Text Block] Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.
FidelityInvestmentGradeBondFund-AMCIZPRO | Fidelity Investment Grade Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments.
FidelityInvestmentGradeBondFund-AMCIZPRO | Fidelity Investment Grade Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
FidelityInvestmentGradeBondFund-AMCIZPRO | Fidelity Investment Grade Bond Fund | HighPortfolioTurnoverMember  
Prospectus Line Items  
Risk [Text Block] High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.
FidelityInvestmentGradeBondFund-AMCIZPRO | Fidelity Investment Grade Bond Fund | ForeignExposureMember  
Prospectus Line Items  
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.
FidelityInvestmentGradeBondFund-AMCIZPRO | Fidelity Investment Grade Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
FidelityShort-TermBondFund-AMCIZPRO | Fidelity Short-Term Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelityShort-TermBondFund-AMCIZPRO | Fidelity Short-Term Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelityShort-TermBondFund-AMCIZPRO | Fidelity Short-Term Bond Fund | LeverageRiskMember  
Prospectus Line Items  
Risk [Text Block] Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.
FidelityShort-TermBondFund-AMCIZPRO | Fidelity Short-Term Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
FidelityShort-TermBondFund-AMCIZPRO | Fidelity Short-Term Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
FidelityShort-TermBondFund-AMCIZPRO | Fidelity Short-Term Bond Fund | ForeignExposureMember  
Prospectus Line Items  
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.
FidelityShort-TermBondFund-AMCIZPRO | Fidelity Short-Term Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
FidelityShort-TermBondFund-RetailPRO | Fidelity Short-Term Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelityShort-TermBondFund-RetailPRO | Fidelity Short-Term Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelityShort-TermBondFund-RetailPRO | Fidelity Short-Term Bond Fund | LeverageRiskMember  
Prospectus Line Items  
Risk [Text Block] Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.
FidelityShort-TermBondFund-RetailPRO | Fidelity Short-Term Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease.
FidelityShort-TermBondFund-RetailPRO | Fidelity Short-Term Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
FidelityShort-TermBondFund-RetailPRO | Fidelity Short-Term Bond Fund | ForeignExposureMember  
Prospectus Line Items  
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.
FidelityShort-TermBondFund-RetailPRO | Fidelity Short-Term Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
FidelitySAISustainableCorePlusBondFund-PRO | Fidelity SAI Sustainable Core Plus Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelitySAISustainableCorePlusBondFund-PRO | Fidelity SAI Sustainable Core Plus Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelitySAISustainableCorePlusBondFund-PRO | Fidelity SAI Sustainable Core Plus Bond Fund | LeverageRiskMember  
Prospectus Line Items  
Risk [Text Block] Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.
FidelitySAISustainableCorePlusBondFund-PRO | Fidelity SAI Sustainable Core Plus Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) and certain types of other securities involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities and certain types of other securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments and can be difficult to resell. Investments in covenant-lite loans carry more risk than traditional loans as they allow issuers to engage in activities that would otherwise be difficult or impossible under a traditional loan agreement. In the event of default, covenant-lite obligations have lower recovery values as the lender may not have the opportunity to negotiate with the borrower prior to default.
FidelitySAISustainableCorePlusBondFund-PRO | Fidelity SAI Sustainable Core Plus Bond Fund | ManagementRiskMember  
Prospectus Line Items  
Risk [Text Block] Management Risk. The Adviser's application of the fund's strategy criteria may not achieve its intended results. The fund could underperform in comparison to other funds with a similar benchmark or similar objectives and investment strategies .
FidelitySAISustainableCorePlusBondFund-PRO | Fidelity SAI Sustainable Core Plus Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
FidelitySAISustainableCorePlusBondFund-PRO | Fidelity SAI Sustainable Core Plus Bond Fund | HighPortfolioTurnoverMember  
Prospectus Line Items  
Risk [Text Block] High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.
FidelitySAISustainableCorePlusBondFund-PRO | Fidelity SAI Sustainable Core Plus Bond Fund | ForeignExposureMember  
Prospectus Line Items  
Risk [Text Block] Foreign Exposure. Foreign markets, particularly emerging 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. Foreign exchange rates also can be extremely volatile.
FidelitySAISustainableCorePlusBondFund-PRO | Fidelity SAI Sustainable Core Plus Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
FidelitySAISustainableCorePlusBondFund-PRO | Fidelity SAI Sustainable Core Plus Bond Fund | SustainabilityRiskMember  
Prospectus Line Items  
Risk [Text Block] Sustainability Risk. Application of Fidelity Management & Research Company LLC's (FMR) (the Adviser) ESG rating 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 rating 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.
FidelitySAITotalBondFund-PRO | Fidelity SAI Total Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelitySAITotalBondFund-PRO | Fidelity SAI Total Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelitySAITotalBondFund-PRO | Fidelity SAI Total Bond Fund | LeverageRiskMember  
Prospectus Line Items  
Risk [Text Block] Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.
FidelitySAITotalBondFund-PRO | Fidelity SAI Total Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) and certain types of other securities involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities and certain types of other securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments and can be difficult to resell. Investments in covenant-lite loans carry more risk than traditional loans as they allow issuers to engage in activities that would otherwise be difficult or impossible under a traditional loan agreement. In the event of default, covenant-lite obligations have lower recovery values as the lender may not have the opportunity to negotiate with the borrower prior to default.
FidelitySAITotalBondFund-PRO | Fidelity SAI Total Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
FidelitySAITotalBondFund-PRO | Fidelity SAI Total Bond Fund | HighPortfolioTurnoverMember  
Prospectus Line Items  
Risk [Text Block] High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.
FidelitySAITotalBondFund-PRO | Fidelity SAI Total Bond Fund | ForeignExposureMember  
Prospectus Line Items  
Risk [Text Block] Foreign Exposure. Foreign markets, particularly emerging 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. Foreign exchange rates also can be extremely volatile.
FidelitySAITotalBondFund-PRO | Fidelity SAI Total Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
FidelitySAIEnhancedCoreBondFund-PRO | Fidelity SAI Enhanced Core Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelitySAIEnhancedCoreBondFund-PRO | Fidelity SAI Enhanced Core Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelitySAIEnhancedCoreBondFund-PRO | Fidelity SAI Enhanced Core Bond Fund | LeverageRiskMember  
Prospectus Line Items  
Risk [Text Block] Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.
FidelitySAIEnhancedCoreBondFund-PRO | Fidelity SAI Enhanced Core Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) and certain types of other securities involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities and certain types of other securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments and can be difficult to resell.
FidelitySAIEnhancedCoreBondFund-PRO | Fidelity SAI Enhanced Core Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
FidelitySAIEnhancedCoreBondFund-PRO | Fidelity SAI Enhanced Core Bond Fund | QuantitativeInvestingMember  
Prospectus Line Items  
Risk [Text Block] Quantitative Investing. Securities selected using quantitative analysis can perform differently from the market as a whole as a result of the factors used in the analysis, the weight placed on each factor, and changes in the factors' historical trends.
FidelitySAIEnhancedCoreBondFund-PRO | Fidelity SAI Enhanced Core Bond Fund | HighPortfolioTurnoverMember  
Prospectus Line Items  
Risk [Text Block] High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.
FidelitySAIEnhancedCoreBondFund-PRO | Fidelity SAI Enhanced Core Bond Fund | ForeignExposureMember  
Prospectus Line Items  
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.
FidelitySAIEnhancedCoreBondFund-PRO | Fidelity SAI Enhanced Core Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
FidelityTacticalBondFund-RetailPRO | Fidelity Tactical Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelityTacticalBondFund-RetailPRO | Fidelity Tactical Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelityTacticalBondFund-RetailPRO | Fidelity Tactical Bond Fund | ForeignAndEmergingMarketsRiskMember  
Prospectus Line Items  
Risk [Text Block] Foreign and Emerging Markets Risk. Foreign markets, particularly emerging 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. The extent of economic development; political stability; market depth, infrastructure, and capitalization; and regulatory oversight can be less than in more developed markets. Emerging markets typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Emerging markets can be subject to greater social, economic, regulatory, and political uncertainties and can be extremely volatile. Foreign exchange rates also can be extremely volatile.
FidelityTacticalBondFund-RetailPRO | Fidelity Tactical Bond Fund | LeverageRiskMember  
Prospectus Line Items  
Risk [Text Block] Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.
FidelityTacticalBondFund-RetailPRO | Fidelity Tactical Bond Fund | ContingentConvertibleSecuritiesRiskMember  
Prospectus Line Items  
Risk [Text Block] Contingent Convertible Securities Risk. Contingent convertible securities have unique equity conversion or principal write-down features that involve additional risks, which may include cancellation of interest payments by the issuer or a regulatory authority; subordination to other creditors due to either a liquidation or other bankruptcy-related event or a conversion of the security from debt to equity; and a write-down of the security's principal amount.
FidelityTacticalBondFund-RetailPRO | Fidelity Tactical Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) and certain types of other securities involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities and certain types of other securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments and can be difficult to resell. CLO tranches can experience substantial losses due to actual and anticipated defaults, as well as aversion to CLO securities as a class. Investments in covenant-lite loans carry more risk than traditional loans as they allow issuers to engage in activities that would otherwise be difficult or impossible under a traditional loan agreement. In the event of default, covenant-lite obligations have lower recovery values as the lender may not have the opportunity to negotiate with the borrower prior to default.
FidelityTacticalBondFund-RetailPRO | Fidelity Tactical Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
FidelityTacticalBondFund-RetailPRO | Fidelity Tactical Bond Fund | ForeignCurrencyTransactionsMember  
Prospectus Line Items  
Risk [Text Block] Foreign Currency Transactions. Although a forward foreign currency exchange contract is used to reduce or hedge a fund's exposure to changes in the value of the currency, suitable hedging transactions may not be available in all circumstances, may not be successful, and may eliminate any chance for the fund to benefit from favorable fluctuations in relevant foreign currencies.
FidelityTacticalBondFund-RetailPRO | Fidelity Tactical Bond Fund | FloatingRateLoanLiquidityMember  
Prospectus Line Items  
Risk [Text Block] Floating Rate Loan Liquidity. Floating rate loans generally are subject to restrictions on resale. Floating rate loans sometimes trade infrequently in the secondary market. As a result, valuing a floating rate loan can be more difficult, and buying and selling a floating rate loan at an acceptable price can be more difficult or delayed, including extended trade settlement periods. Difficulty in selling a floating rate loan can result in a loss.
FidelityTacticalBondFund-RetailPRO | Fidelity Tactical Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
FidelityTacticalBondFund-RetailPRO | Fidelity Tactical Bond Fund | InflationProtectedDebtExposureMember  
Prospectus Line Items  
Risk [Text Block] Inflation-Protected Debt Exposure. Increases in real interest rates can cause the price of inflation-protected debt securities to decrease. Interest payments on inflation-protected debt securities can be unpredictable.
FidelityTacticalBondFund-RetailPRO | Fidelity Tactical Bond Fund | ImpairmentOfCollateralMember  
Prospectus Line Items  
Risk [Text Block] Impairment of Collateral. A floating rate loan may not be fully collateralized which may cause the floating rate loan to decline significantly in value.
FidelityInvestmentGradeBondFund-RetailPRO | Fidelity Investment Grade Bond Fund | Risk Lose Money [Member]  
Prospectus Line Items  
Risk [Text Block]   You could lose money by investing in the fund.
FidelityInvestmentGradeBondFund-RetailPRO | Fidelity Investment Grade Bond Fund | Risk Not Insured Depository Institution [Member]  
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 .
FidelityInvestmentGradeBondFund-RetailPRO | Fidelity Investment Grade Bond Fund | LeverageRiskMember  
Prospectus Line Items  
Risk [Text Block] Leverage Risk. Leverage can increase market exposure, magnify investment risks, and cause losses to be realized more quickly.
FidelityInvestmentGradeBondFund-RetailPRO | Fidelity Investment Grade Bond Fund | 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. A decline in the credit quality of an issuer or a provider of credit support (such as guarantees) or a maturity-shortening structure (such as demand and put features) for a security can cause the price of a security to decrease. Lower-quality debt securities (those of less than investment-grade quality, also referred to as high yield debt securities or junk bonds) involve greater risk of default or price changes due to changes in the credit quality of the issuer. The value of lower-quality debt securities can be more volatile due to increased sensitivity to adverse issuer, political, regulatory, market, or economic developments.
FidelityInvestmentGradeBondFund-RetailPRO | Fidelity Investment Grade Bond Fund | InterestRateChangesMember  
Prospectus Line Items  
Risk [Text Block] Interest Rate Changes. Interest rate increases can cause the price of a debt security to decrease.
FidelityInvestmentGradeBondFund-RetailPRO | Fidelity Investment Grade Bond Fund | HighPortfolioTurnoverMember  
Prospectus Line Items  
Risk [Text Block] High Portfolio Turnover. High portfolio turnover (more than 100%) may result in increased transaction costs and potentially higher capital gains or losses. The effects of higher than normal portfolio turnover may adversely affect the fund's performance.
FidelityInvestmentGradeBondFund-RetailPRO | Fidelity Investment Grade Bond Fund | ForeignExposureMember  
Prospectus Line Items  
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.
FidelityInvestmentGradeBondFund-RetailPRO | Fidelity Investment Grade Bond Fund | PrepaymentMember  
Prospectus Line Items  
Risk [Text Block] Prepayment. The ability of an issuer of a debt security to repay principal prior to a security's maturity can cause greater price volatility if interest rates change.
Document Type 485BPOS