v3.26.1
Shareholder Report, Holdings (Details)
Jan. 31, 2026
Fidelity Tax-Free Bond Fund | TS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.60%
Fidelity Tax-Free Bond Fund | TS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 9.40%
Fidelity Tax-Free Bond Fund | TS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 9.30%
Fidelity Tax-Free Bond Fund | TS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Fidelity Tax-Free Bond Fund | TS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.80%
Fidelity Tax-Free Bond Fund | RS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 34.80%
Fidelity Tax-Free Bond Fund | RS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.00%
Fidelity Tax-Free Bond Fund | RS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.90%
Fidelity Tax-Free Bond Fund | RS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.40%
Fidelity Tax-Free Bond Fund | RS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.80%
Fidelity Tax-Free Bond Fund | RS5Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Fidelity Tax-Free Bond Fund | RS6Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.60%
Fidelity Tax-Free Bond Fund | QDAAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
Fidelity Tax-Free Bond Fund | QDAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 37.90%
Fidelity Tax-Free Bond Fund | QDAMember  
Holdings [Line Items]  
Percent of Net Asset Value 37.50%
Fidelity Tax-Free Bond Fund | QDBBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 6.60%
Fidelity Tax-Free Bond Fund | QDBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
Fidelity Tax-Free Bond Fund | QDBMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity Tax-Free Bond Fund | QDCCCCCCMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Tax-Free Bond Fund | QDNotRatedMember  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Tax-Free Bond Fund | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 7.10%
Fidelity Sustainable Intermediate Municipal Income Fund | TS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.80%
Fidelity Sustainable Intermediate Municipal Income Fund | TS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.20%
Fidelity Sustainable Intermediate Municipal Income Fund | TS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.90%
Fidelity Sustainable Intermediate Municipal Income Fund | TS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
Fidelity Sustainable Intermediate Municipal Income Fund | TS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
Fidelity Sustainable Intermediate Municipal Income Fund | RS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 36.80%
Fidelity Sustainable Intermediate Municipal Income Fund | RS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.40%
Fidelity Sustainable Intermediate Municipal Income Fund | RS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%
Fidelity Sustainable Intermediate Municipal Income Fund | RS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 9.50%
Fidelity Sustainable Intermediate Municipal Income Fund | RS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.10%
Fidelity Sustainable Intermediate Municipal Income Fund | RS5Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Fidelity Sustainable Intermediate Municipal Income Fund | RS6Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Sustainable Intermediate Municipal Income Fund | RS7Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Fidelity Sustainable Intermediate Municipal Income Fund | RS8Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.10%
Fidelity Sustainable Intermediate Municipal Income Fund | QDAAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 12.40%
Fidelity Sustainable Intermediate Municipal Income Fund | QDAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 53.40%
Fidelity Sustainable Intermediate Municipal Income Fund | QDAMember  
Holdings [Line Items]  
Percent of Net Asset Value 22.70%
Fidelity Sustainable Intermediate Municipal Income Fund | QDBBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 6.60%
Fidelity Sustainable Intermediate Municipal Income Fund | QDBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Sustainable Intermediate Municipal Income Fund | QDNotRatedMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Sustainable Intermediate Municipal Income Fund | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | TS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.80%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | TS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | TS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.90%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | TS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | TS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | RS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 36.80%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | RS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | RS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | RS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 9.50%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | RS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | RS5Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | RS6Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | RS7Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | RS8Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | QDAAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 12.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | QDAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 53.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | QDAMember  
Holdings [Line Items]  
Percent of Net Asset Value 22.70%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | QDBBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 6.60%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | QDBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | QDNotRatedMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class Z | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | TS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.80%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | TS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | TS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.90%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | TS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | TS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | RS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 36.80%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | RS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | RS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | RS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 9.50%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | RS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | RS5Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | RS6Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | RS7Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | RS8Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | QDAAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 12.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | QDAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 53.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | QDAMember  
Holdings [Line Items]  
Percent of Net Asset Value 22.70%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | QDBBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 6.60%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | QDBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | QDNotRatedMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class M | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | TS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.80%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | TS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | TS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.90%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | TS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | TS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | RS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 36.80%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | RS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | RS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | RS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 9.50%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | RS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | RS5Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | RS6Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | RS7Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | RS8Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | QDAAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 12.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | QDAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 53.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | QDAMember  
Holdings [Line Items]  
Percent of Net Asset Value 22.70%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | QDBBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 6.60%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | QDBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | QDNotRatedMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class I | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | TS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.80%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | TS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | TS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.90%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | TS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | TS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | RS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 36.80%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | RS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | RS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | RS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 9.50%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | RS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | RS5Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | RS6Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | RS7Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | RS8Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | QDAAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 12.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | QDAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 53.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | QDAMember  
Holdings [Line Items]  
Percent of Net Asset Value 22.70%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | QDBBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 6.60%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | QDBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | QDNotRatedMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class C | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | TS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.80%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | TS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | TS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.90%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | TS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | TS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | RS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 36.80%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | RS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | RS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | RS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 9.50%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | RS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | RS5Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | RS6Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | RS7Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.00%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | RS8Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.10%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | QDAAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 12.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | QDAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 53.40%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | QDAMember  
Holdings [Line Items]  
Percent of Net Asset Value 22.70%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | QDBBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 6.60%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | QDBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.30%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | QDNotRatedMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Advisor Sustainable Intermediate Municipal Income Fund - Class A | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity Series Large Cap Value Index Fund | TH0Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.80%
Fidelity Series Large Cap Value Index Fund | TH1Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.80%
Fidelity Series Large Cap Value Index Fund | TH2Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.30%
Fidelity Series Large Cap Value Index Fund | TH3Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.10%
Fidelity Series Large Cap Value Index Fund | TH4Member  
Holdings [Line Items]  
Percent of Net Asset Value 2.00%
Fidelity Series Large Cap Value Index Fund | TH5Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
Fidelity Series Large Cap Value Index Fund | TH6Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.80%
Fidelity Series Large Cap Value Index Fund | TH7Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.60%
Fidelity Series Large Cap Value Index Fund | TH8Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.50%
Fidelity Series Large Cap Value Index Fund | TH9Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.20%
Fidelity Series Large Cap Value Index Fund | MSFinancialsSectorMember  
Holdings [Line Items]  
Percent of Net Asset Value 20.90%
Fidelity Series Large Cap Value Index Fund | Information Technology Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.80%
Fidelity Series Large Cap Value Index Fund | Healthcare Sector  
Holdings [Line Items]  
Percent of Net Asset Value 11.80%
Fidelity Series Large Cap Value Index Fund | Real Estate Sector  
Holdings [Line Items]  
Percent of Net Asset Value 3.90%
Fidelity Series Large Cap Value Index Fund | Industrial Sector Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.60%
Fidelity Series Large Cap Value Index Fund | Materials Sector Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.30%
Fidelity Series Large Cap Value Index Fund | Consumer Discretionary Sector Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.30%
Fidelity Series Large Cap Value Index Fund | Consumer Staples Sector Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.40%
Fidelity Series Large Cap Value Index Fund | Communications Sector Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.40%
Fidelity Series Large Cap Value Index Fund | Energy Sector  
Holdings [Line Items]  
Percent of Net Asset Value 6.30%
Fidelity Series Large Cap Value Index Fund | Utilities Sector Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.20%
Fidelity Series Large Cap Value Index Fund | United States  
Holdings [Line Items]  
Percent of Net Asset Value 99.40%
Fidelity Series Large Cap Value Index Fund | Canada  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Series Large Cap Value Index Fund | Australia  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity Series Large Cap Value Index Fund | United Kingdom  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Series Large Cap Value Index Fund | Mexico  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity Series Large Cap Value Index Fund | Bermuda  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Series Large Cap Value Index Fund | Puerto Rico  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Series Large Cap Value Index Fund | Brazil  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Series Large Cap Value Index Fund | Guatemala  
Holdings [Line Items]  
Percent of Net Asset Value 0.00%
Fidelity Series Large Cap Value Index Fund | AACommonStocksMember  
Holdings [Line Items]  
Percent of Net Asset Value 99.90%
Fidelity Series Large Cap Value Index Fund | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.10%
Fidelity SAI Tax-Free Bond Fund | TS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 12.80%
Fidelity SAI Tax-Free Bond Fund | TS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.30%
Fidelity SAI Tax-Free Bond Fund | TS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.40%
Fidelity SAI Tax-Free Bond Fund | TS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
Fidelity SAI Tax-Free Bond Fund | TS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.20%
Fidelity SAI Tax-Free Bond Fund | RS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 34.40%
Fidelity SAI Tax-Free Bond Fund | RS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 12.90%
Fidelity SAI Tax-Free Bond Fund | RS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.20%
Fidelity SAI Tax-Free Bond Fund | RS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.90%
Fidelity SAI Tax-Free Bond Fund | RS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.70%
Fidelity SAI Tax-Free Bond Fund | RS5Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.40%
Fidelity SAI Tax-Free Bond Fund | RS6Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
Fidelity SAI Tax-Free Bond Fund | RS7Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.10%
Fidelity SAI Tax-Free Bond Fund | RS8Member  
Holdings [Line Items]  
Percent of Net Asset Value 1.40%
Fidelity SAI Tax-Free Bond Fund | QDAAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 5.50%
Fidelity SAI Tax-Free Bond Fund | QDAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 45.20%
Fidelity SAI Tax-Free Bond Fund | QDAMember  
Holdings [Line Items]  
Percent of Net Asset Value 30.80%
Fidelity SAI Tax-Free Bond Fund | QDBBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 5.60%
Fidelity SAI Tax-Free Bond Fund | QDBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.00%
Fidelity SAI Tax-Free Bond Fund | QDBMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity SAI Tax-Free Bond Fund | QDNotRatedMember  
Holdings [Line Items]  
Percent of Net Asset Value 3.00%
Fidelity SAI Tax-Free Bond Fund | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 8.70%
Fidelity SAI Sustainable Municipal Income Fund | TS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.70%
Fidelity SAI Sustainable Municipal Income Fund | TS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 9.50%
Fidelity SAI Sustainable Municipal Income Fund | TS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.20%
Fidelity SAI Sustainable Municipal Income Fund | TS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.80%
Fidelity SAI Sustainable Municipal Income Fund | TS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.60%
Fidelity SAI Sustainable Municipal Income Fund | RS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 34.30%
Fidelity SAI Sustainable Municipal Income Fund | RS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 14.30%
Fidelity SAI Sustainable Municipal Income Fund | RS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 11.70%
Fidelity SAI Sustainable Municipal Income Fund | RS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.50%
Fidelity SAI Sustainable Municipal Income Fund | RS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.30%
Fidelity SAI Sustainable Municipal Income Fund | RS5Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.10%
Fidelity SAI Sustainable Municipal Income Fund | RS6Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.50%
Fidelity SAI Sustainable Municipal Income Fund | RS7Member  
Holdings [Line Items]  
Percent of Net Asset Value 3.40%
Fidelity SAI Sustainable Municipal Income Fund | QDAAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 13.50%
Fidelity SAI Sustainable Municipal Income Fund | QDAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 56.60%
Fidelity SAI Sustainable Municipal Income Fund | QDAMember  
Holdings [Line Items]  
Percent of Net Asset Value 24.00%
Fidelity SAI Sustainable Municipal Income Fund | QDBBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity SAI Sustainable Municipal Income Fund | QDBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity SAI Sustainable Municipal Income Fund | QDNotRatedMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.20%
Fidelity SAI Sustainable Municipal Income Fund | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 1.90%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | TS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.20%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | TS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 9.70%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | TS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.70%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | TS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.10%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | TS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 6.80%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | RS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 21.40%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | RS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 16.30%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | RS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 14.80%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | RS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 12.80%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | RS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.90%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | RS5Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.50%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | RS6Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.70%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | RS7Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.30%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | QDAAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 4.30%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | QDAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 32.10%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | QDAMember  
Holdings [Line Items]  
Percent of Net Asset Value 57.40%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | QDBBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.60%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | QDNotRatedMember  
Holdings [Line Items]  
Percent of Net Asset Value 5.30%
Fidelity SAI Sustainable Conservative Income Municipal Bond Fund | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 0.30%
Fidelity SAI Conservative Income Municipal Bond Fund | TS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 13.90%
Fidelity SAI Conservative Income Municipal Bond Fund | TS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 9.90%
Fidelity SAI Conservative Income Municipal Bond Fund | TS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.50%
Fidelity SAI Conservative Income Municipal Bond Fund | TS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.80%
Fidelity SAI Conservative Income Municipal Bond Fund | TS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 5.80%
Fidelity SAI Conservative Income Municipal Bond Fund | RS0Member  
Holdings [Line Items]  
Percent of Net Asset Value 20.70%
Fidelity SAI Conservative Income Municipal Bond Fund | RS1Member  
Holdings [Line Items]  
Percent of Net Asset Value 18.00%
Fidelity SAI Conservative Income Municipal Bond Fund | RS2Member  
Holdings [Line Items]  
Percent of Net Asset Value 10.70%
Fidelity SAI Conservative Income Municipal Bond Fund | RS3Member  
Holdings [Line Items]  
Percent of Net Asset Value 9.90%
Fidelity SAI Conservative Income Municipal Bond Fund | RS4Member  
Holdings [Line Items]  
Percent of Net Asset Value 9.30%
Fidelity SAI Conservative Income Municipal Bond Fund | RS5Member  
Holdings [Line Items]  
Percent of Net Asset Value 8.60%
Fidelity SAI Conservative Income Municipal Bond Fund | RS6Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.30%
Fidelity SAI Conservative Income Municipal Bond Fund | RS7Member  
Holdings [Line Items]  
Percent of Net Asset Value 7.20%
Fidelity SAI Conservative Income Municipal Bond Fund | RS8Member  
Holdings [Line Items]  
Percent of Net Asset Value 4.30%
Fidelity SAI Conservative Income Municipal Bond Fund | QDAAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 3.50%
Fidelity SAI Conservative Income Municipal Bond Fund | QDAAMember  
Holdings [Line Items]  
Percent of Net Asset Value 29.80%
Fidelity SAI Conservative Income Municipal Bond Fund | QDAMember  
Holdings [Line Items]  
Percent of Net Asset Value 43.00%
Fidelity SAI Conservative Income Municipal Bond Fund | QDBBBMember  
Holdings [Line Items]  
Percent of Net Asset Value 7.60%
Fidelity SAI Conservative Income Municipal Bond Fund | QDNotRatedMember  
Holdings [Line Items]  
Percent of Net Asset Value 12.10%
Fidelity SAI Conservative Income Municipal Bond Fund | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember  
Holdings [Line Items]  
Percent of Net Asset Value 4.00%