Fidelity SAI U.S. Treasury Bond Index Fund (FUTBX) N-CSR 24 Oct 24 Certified annual shareholder report (management investment company) Financial data

Form N-CSR Cover

Form N-CSR Cover	12 Months Ended
	Aug. 31, 2024
Shareholder Report [Line Items]
Document Type	N-CSR
Amendment Flag	false
Registrant Name	Fidelity Salem Street Trust
Entity Central Index Key	0000035315
Entity Investment Company Type	N-1A
Document Period End Date	Aug. 31, 2024

Shareholder Report

Shareholder Report	12 Months Ended
	Aug. 31, 2024 USD ($) shares
Shareholder Report [Line Items]
Document Type	N-CSR
Amendment Flag	false
Registrant Name	Fidelity Salem Street Trust
Entity Central Index Key	0000035315
Entity Investment Company Type	N-1A
Document Period End Date	Aug. 31, 2024
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I
Shareholder Report [Line Items]
Fund Name	Fidelity® Sustainable Core Plus Bond Fund
Class Name	Fidelity Advisor® Sustainable Core Plus Bond Fund Class I
Trading Symbol	FIALX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Sustainable Core Plus Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-877-208-0098
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class I $ 0.42 %
Expenses Paid, Amount	$ 44
Expense Ratio, Percent	0.42%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B26">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE April 13, 2022 through August 31, 2024. Initial investment of $10,000. Class I   $10,000 $9,594   $9,553   Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index   $10,000 $9,703   $9,590   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,696   $9,581     2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Class I 7.66% 1.18% Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index 7.26% 1.19% Bloomberg U.S. Aggregate Bond Index 7.30% 1.16% A   From April 13, 2022   Visit institutional.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Apr. 13, 2022
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 39,262,600
Holdings Count | shares	597
Advisory Fees Paid, Amount	$ 121,381
Investment Company Portfolio Turnover	334%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 597 Total Advisory Fee $ Portfolio Turnover 334 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 57.2 AAA 6.4 AA 1.0 A 11.6 BBB 16.3 BB 2.7 B 2.8 CCC,CC,C 1.5 Not Rated 2.1 Equities 0.0 QUALITY DIVERSIFICATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (1.6)%   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     U.S. Treasury Obligations 35.7 Corporate Bonds 35.2 U.S. Government Agency - Mortgage Securities 21.5 Asset-Backed Securities 7.5 CMOs and Other Mortgage Related Securities 0.9 Preferred Securities 0.4 Bank Loan Obligations 0.2 Foreign Government and Government Agency Obligations 0.2 Common Stocks 0.0 ASSET ALLOCATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (1.6)% United States 85.3 Grand Cayman (UK Overseas Ter) 5.1 United Kingdom 1.5 Bailiwick Of Jersey 1.3 Canada 1.2 Netherlands 0.8 Germany 0.7 Multi-national 0.6 Italy 0.5 Others 3.0 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Notes 25.0     US Treasury Bonds 10.6     Uniform Mortgage Backed Securities 10.1     Ginnie Mae II Pool 5.4     Fannie Mae Mortgage pass-thru certificates 3.2     Freddie Mac Gold Pool 2.4     Symphony Clo Xxvi Ltd / Symphony Clo Xxvi LLC 1.5     Bank of America Corp 1.4     Morgan Stanley 1.0     Citigroup Inc 0.9       61.5
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Operating expenses The fund modified its principal investment risks during the reporting period.
Material Fund Change Expenses [Text Block]	The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Operating expenses
Material Fund Change Risks Change [Text Block]	The fund modified its principal investment risks during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-877-208-0098</span>" id="sjs-B42">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B43">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B44">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C
Shareholder Report [Line Items]
Fund Name	Fidelity® Sustainable Core Plus Bond Fund
Class Name	Fidelity Advisor® Sustainable Core Plus Bond Fund Class C
Trading Symbol	FIAJX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Sustainable Core Plus Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-877-208-0098
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class C $ 1.41 %
Expenses Paid, Amount	$ 146
Expense Ratio, Percent	1.41%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B61">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE April 13, 2022 through August 31, 2024. Initial investment of $10,000. Class C   $10,000 $9,559   $9,423   Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index   $10,000 $9,703   $9,590   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,696   $9,581     2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Class C  (incl. contingent deferred sales charge) 5.60% 0.19% Class C 6.60% 0.19% Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index 7.26% 1.19% Bloomberg U.S. Aggregate Bond Index 7.30% 1.16% A   From April 13, 2022   Visit institutional.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Apr. 13, 2022
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 39,262,600
Holdings Count | shares	597
Advisory Fees Paid, Amount	$ 121,381
Investment Company Portfolio Turnover	334%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 597 Total Advisory Fee $ Portfolio Turnover 334 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 57.2 AAA 6.4 AA 1.0 A 11.6 BBB 16.3 BB 2.7 B 2.8 CCC,CC,C 1.5 Not Rated 2.1 Equities 0.0 QUALITY DIVERSIFICATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (1.6)%   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     U.S. Treasury Obligations 35.7 Corporate Bonds 35.2 U.S. Government Agency - Mortgage Securities 21.5 Asset-Backed Securities 7.5 CMOs and Other Mortgage Related Securities 0.9 Preferred Securities 0.4 Bank Loan Obligations 0.2 Foreign Government and Government Agency Obligations 0.2 Common Stocks 0.0 ASSET ALLOCATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (1.6)% United States 85.3 Grand Cayman (UK Overseas Ter) 5.1 United Kingdom 1.5 Bailiwick Of Jersey 1.3 Canada 1.2 Netherlands 0.8 Germany 0.7 Multi-national 0.6 Italy 0.5 Others 3.0 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Notes 25.0     US Treasury Bonds 10.6     Uniform Mortgage Backed Securities 10.1     Ginnie Mae II Pool 5.4     Fannie Mae Mortgage pass-thru certificates 3.2     Freddie Mac Gold Pool 2.4     Symphony Clo Xxvi Ltd / Symphony Clo Xxvi LLC 1.5     Bank of America Corp 1.4     Morgan Stanley 1.0     Citigroup Inc 0.9       61.5
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fund modified its principal investment risks during the reporting period.
Material Fund Change Risks Change [Text Block]	The fund modified its principal investment risks during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-877-208-0098</span>" id="sjs-B76">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B77">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B78">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I
Shareholder Report [Line Items]
Fund Name	Fidelity® Sustainable Low Duration Bond Fund
Class Name	Fidelity Advisor® Sustainable Low Duration Bond Fund Class I
Trading Symbol	FAPDX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Sustainable Low Duration Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-877-208-0098
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class I $ 0.25 %
Expenses Paid, Amount	$ 26
Expense Ratio, Percent	0.25%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B95">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE April 13, 2022 through August 31, 2024. Initial investment of $10,000. Class I   $10,000 $10,001   $10,404   Bloomberg US Treasury Bill: 6-9 Months Index   $10,000 $9,990   $10,301   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,696   $9,581     2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Class I 5.79% 4.10% Bloomberg US Treasury Bill: 6-9 Months Index 5.37% 3.49% Bloomberg U.S. Aggregate Bond Index 7.30% 1.16% A   From April 13, 2022   Visit institutional.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Apr. 13, 2022
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 29,475,941
Holdings Count | shares	267
Advisory Fees Paid, Amount	$ 53,128
Investment Company Portfolio Turnover	67%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 267 Total Advisory Fee $ Portfolio Turnover 67 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 25.8 AAA 10.9 AA 1.7 A 26.7 BBB 30.6 Short-Term Investments and Net Other Assets (Liabilities) 4.3 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     Corporate Bonds 58.1 U.S. Treasury Obligations 25.8 Asset-Backed Securities 10.6 Other Investments 0.9 CMOs and Other Mortgage Related Securities 0.3 Short-Term Investments and Net Other Assets (Liabilities) 4.3 ASSET ALLOCATION (% of Fund's net assets)   United States 91.4 Canada 6.5 Netherlands 0.8 China 0.8 Germany 0.5 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Bill 25.8     General Motors Financial Co Inc 2.0     Morgan Stanley 1.9     Bank of America Corp 1.9     Goldman Sachs Group Inc/The 1.7     Equitable Financial Life Global Funding 1.7     Capital One Financial Corp 1.6     Wells Fargo & Co 1.6     Hyundai Capital America 1.6     JPMorgan Chase & Co 1.3       41.1
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses The fund modified its principal investment risks during the reporting period.
Material Fund Change Expenses [Text Block]	The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses
Material Fund Change Risks Change [Text Block]	The fund modified its principal investment risks during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-877-208-0098</span>" id="sjs-B111">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B112">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B113">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A
Shareholder Report [Line Items]
Fund Name	Fidelity® Sustainable Core Plus Bond Fund
Class Name	Fidelity Advisor® Sustainable Core Plus Bond Fund Class A
Trading Symbol	FIAIX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Sustainable Core Plus Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-877-208-0098
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class A $ 0.68 %
Expenses Paid, Amount	$ 71
Expense Ratio, Percent	0.68%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B130">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE April 13, 2022 through August 31, 2024. Initial investment of $10,000 and the current sales charge was paid. Class A   $9,600 $9,202   $9,137   Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index   $10,000 $9,703   $9,590   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,696   $9,581     2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Class A (incl. 4.00% sales charge)   3.09% -0.79% Class A (without 4.00% sales charge) 7.38% 0.92% Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index 7.26% 1.19% Bloomberg U.S. Aggregate Bond Index 7.30% 1.16% A   From April 13, 2022   Visit institutional.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Apr. 13, 2022
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 39,262,600
Holdings Count | shares	597
Advisory Fees Paid, Amount	$ 121,381
Investment Company Portfolio Turnover	334%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 597 Total Advisory Fee $ Portfolio Turnover 334 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 57.2 AAA 6.4 AA 1.0 A 11.6 BBB 16.3 BB 2.7 B 2.8 CCC,CC,C 1.5 Not Rated 2.1 Equities 0.0 QUALITY DIVERSIFICATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (1.6)%   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     U.S. Treasury Obligations 35.7 Corporate Bonds 35.2 U.S. Government Agency - Mortgage Securities 21.5 Asset-Backed Securities 7.5 CMOs and Other Mortgage Related Securities 0.9 Preferred Securities 0.4 Bank Loan Obligations 0.2 Foreign Government and Government Agency Obligations 0.2 Common Stocks 0.0 ASSET ALLOCATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (1.6)% United States 85.3 Grand Cayman (UK Overseas Ter) 5.1 United Kingdom 1.5 Bailiwick Of Jersey 1.3 Canada 1.2 Netherlands 0.8 Germany 0.7 Multi-national 0.6 Italy 0.5 Others 3.0 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Notes 25.0     US Treasury Bonds 10.6     Uniform Mortgage Backed Securities 10.1     Ginnie Mae II Pool 5.4     Fannie Mae Mortgage pass-thru certificates 3.2     Freddie Mac Gold Pool 2.4     Symphony Clo Xxvi Ltd / Symphony Clo Xxvi LLC 1.5     Bank of America Corp 1.4     Morgan Stanley 1.0     Citigroup Inc 0.9       61.5
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fund modified its principal investment risks during the reporting period.
Material Fund Change Risks Change [Text Block]	The fund modified its principal investment risks during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-877-208-0098</span>" id="sjs-B145">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B146">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B147">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A
Shareholder Report [Line Items]
Fund Name	Fidelity® Sustainable Low Duration Bond Fund
Class Name	Fidelity Advisor® Sustainable Low Duration Bond Fund Class A
Trading Symbol	FAMZX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Sustainable Low Duration Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-877-208-0098
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class A $ 0.45 %
Expenses Paid, Amount	$ 46
Expense Ratio, Percent	0.45%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B164">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE April 13, 2022 through August 31, 2024. Initial investment of $10,000 and the current sales charge was paid. Class A   $9,850 $9,845   $10,221   Bloomberg US Treasury Bill: 6-9 Months Index   $10,000 $9,990   $10,301   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,696   $9,581     2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Class A (incl. 1.50% sales charge)   3.99% 3.24% Class A (without 1.50% sales charge) 5.58% 3.90% Bloomberg US Treasury Bill: 6-9 Months Index 5.37% 3.49% Bloomberg U.S. Aggregate Bond Index 7.30% 1.16% A   From April 13, 2022   Visit institutional.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Apr. 13, 2022
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 29,475,941
Holdings Count | shares	267
Advisory Fees Paid, Amount	$ 53,128
Investment Company Portfolio Turnover	67%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 267 Total Advisory Fee $ Portfolio Turnover 67 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 25.8 AAA 10.9 AA 1.7 A 26.7 BBB 30.6 Short-Term Investments and Net Other Assets (Liabilities) 4.3 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     Corporate Bonds 58.1 U.S. Treasury Obligations 25.8 Asset-Backed Securities 10.6 Other Investments 0.9 CMOs and Other Mortgage Related Securities 0.3 Short-Term Investments and Net Other Assets (Liabilities) 4.3 ASSET ALLOCATION (% of Fund's net assets)   United States 91.4 Canada 6.5 Netherlands 0.8 China 0.8 Germany 0.5 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Bill 25.8     General Motors Financial Co Inc 2.0     Morgan Stanley 1.9     Bank of America Corp 1.9     Goldman Sachs Group Inc/The 1.7     Equitable Financial Life Global Funding 1.7     Capital One Financial Corp 1.6     Wells Fargo & Co 1.6     Hyundai Capital America 1.6     JPMorgan Chase & Co 1.3       41.1
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses The fund modified its principal investment risks during the reporting period.
Material Fund Change Expenses [Text Block]	The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses
Material Fund Change Risks Change [Text Block]	The fund modified its principal investment risks during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-877-208-0098</span>" id="sjs-B180">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B181">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B182">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Series Sustainable Investment Grade Bond Fund
Shareholder Report [Line Items]
Fund Name	Fidelity® Series Sustainable Investment Grade Bond Fund
Class Name	Fidelity® Series Sustainable Investment Grade Bond Fund
Trading Symbol	FIGDX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Series Sustainable Investment Grade Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544.
Additional Information Phone Number	1-800-544-8544
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Fidelity® Series Sustainable Investment Grade Bond Fund $ A 0.00 % B A Amount represents less than $.50 B Amount represents less than 0.005%
Expenses Paid, Amount	$ 0
Expense Ratio, Percent	0%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B197">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE May 11, 2023 through August 31, 2024. Initial investment of $10,000. Fidelity® Series Sustainable Investment Grade Bond Fund   $10,000 $9,778   Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index   $10,000 $9,772   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,768     2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Fidelity® Series Sustainable Investment Grade Bond Fund 7.42% 3.82% Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index 7.26% 3.66% Bloomberg U.S. Aggregate Bond Index 7.30% 3.65% A   From May 11, 2023   Visit www.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	May 11, 2023
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 8,246,880
Holdings Count | shares	126
Advisory Fees Paid, Amount	$ 0
Investment Company Portfolio Turnover	405%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 126 Total Advisory Fee $ Portfolio Turnover 405 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 66.7 AAA 3.1 AA 0.8 A 10.4 BBB 13.0 BB 0.2 Not Rated 3.0 Short-Term Investments and Net Other Assets (Liabilities) 2.8 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     U.S. Treasury Obligations 44.9 Corporate Bonds 24.4 U.S. Government Agency - Mortgage Securities 21.8 Asset-Backed Securities 6.1 Short-Term Investments and Net Other Assets (Liabilities) 2.8 ASSET ALLOCATION (% of Fund's net assets) United States 92.5 Grand Cayman (UK Overseas Ter) 6.1 Canada 0.7 China 0.4 United Kingdom 0.3 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Notes 32.5     US Treasury Bonds 11.3     Uniform Mortgage Backed Securities 9.3     Fannie Mae Mortgage pass-thru certificates 5.1     Ginnie Mae II Pool 4.9     RR 28 LTD / RR 28 LLC 3.1     Allegro Clo Xii Ltd 3.0     Bank of America Corp 1.6     Morgan Stanley 1.4     Freddie Mac Gold Pool 1.2       73.4
Fidelity Short-Term Bond Index Fund
Shareholder Report [Line Items]
Fund Name	Fidelity® Short-Term Bond Index Fund
Class Name	Fidelity® Short-Term Bond Index Fund
Trading Symbol	FNSOX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Short-Term Bond Index Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com.
Additional Information Phone Number	1-800-544-8544
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Fidelity® Short-Term Bond Index Fund $ 0.03 %
Expenses Paid, Amount	$ 3
Expense Ratio, Percent	0.03%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • •
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B224">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE October 18, 2017 through August 31, 2024. Initial investment of $10,000. Fidelity® Short-Term Bond Index Fund   $10,000 $9,969   $10,565   $11,052   $11,073   $10,427   $10,551   $11,255   Bloomberg U.S. 1-5 Year Government/Credit Bond Index   $10,000 $9,990   $10,586   $11,086   $11,122   $10,472   $10,596   $11,303   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,938   $10,949   $11,658   $11,648   $10,307   $10,184   $10,927     2017 2018 2019 2020 2021 2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year 5 Year Life of Fund A Fidelity® Short-Term Bond Index Fund 6.68% 1.27% 1.74% Bloomberg U.S. 1-5 Year Government/Credit Bond Index 6.67% 1.32% 1.80% Bloomberg U.S. Aggregate Bond Index 7.30% -0.04% 1.30% A   From October 18, 2017   Visit www.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Oct. 18, 2017
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 2,772,790,791
Holdings Count | shares	1,262
Advisory Fees Paid, Amount	$ 732,285
Investment Company Portfolio Turnover	80%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 1,262 Total Advisory Fee $ Portfolio Turnover 80 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 67.5 AAA 3.3 AA 2.9 A 13.4 BBB 12.2 BB 0.5 Short-Term Investments and Net Other Assets (Liabilities) 0.2 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     U.S. Treasury Obligations 65.3 Corporate Bonds 28.7 U.S. Government Agency Obligations 2.2 Supranational Obligations 2.0 Foreign Government and Government Agency Obligations 1.3 Other Investments 0.3 Short-Term Investments and Net Other Assets (Liabilities) 0.2 ASSET ALLOCATION (% of Fund's net assets)   United States 90.5 Multi-national 2.1 Canada 1.7 United Kingdom 1.6 Japan 1.2 Germany 0.6 Australia 0.4 Spain 0.3 Ireland 0.2 Others 1.4 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Notes 65.3     Bank of America Corp 1.0     Fannie Mae 0.9     JPMorgan Chase & Co 0.8     Morgan Stanley 0.8     Federal Home Loan Bank 0.7     HSBC Holdings PLC 0.7     Goldman Sachs Group Inc/The 0.6     Asian Development Bank 0.6     International Bank for Reconstruction & Development 0.5       71.9
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z
Shareholder Report [Line Items]
Fund Name	Fidelity® Sustainable Low Duration Bond Fund
Class Name	Fidelity Advisor® Sustainable Low Duration Bond Fund Class Z
Trading Symbol	FAPEX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Sustainable Low Duration Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-877-208-0098
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class Z $ 0.20 %
Expenses Paid, Amount	$ 21
Expense Ratio, Percent	0.20%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B252">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE April 13, 2022 through August 31, 2024. Initial investment of $10,000. Class Z   $10,000 $10,003   $10,411   Bloomberg US Treasury Bill: 6-9 Months Index   $10,000 $9,990   $10,301   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,696   $9,581     2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Class Z 5.84% 4.15% Bloomberg US Treasury Bill: 6-9 Months Index 5.37% 3.49% Bloomberg U.S. Aggregate Bond Index 7.30% 1.16% A   From April 13, 2022   Visit institutional.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Apr. 13, 2022
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 29,475,941
Holdings Count | shares	267
Advisory Fees Paid, Amount	$ 53,128
Investment Company Portfolio Turnover	67%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 267 Total Advisory Fee $ Portfolio Turnover 67 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 25.8 AAA 10.9 AA 1.7 A 26.7 BBB 30.6 Short-Term Investments and Net Other Assets (Liabilities) 4.3 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     Corporate Bonds 58.1 U.S. Treasury Obligations 25.8 Asset-Backed Securities 10.6 Other Investments 0.9 CMOs and Other Mortgage Related Securities 0.3 Short-Term Investments and Net Other Assets (Liabilities) 4.3 ASSET ALLOCATION (% of Fund's net assets)   United States 91.4 Canada 6.5 Netherlands 0.8 China 0.8 Germany 0.5 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Bill 25.8     General Motors Financial Co Inc 2.0     Morgan Stanley 1.9     Bank of America Corp 1.9     Goldman Sachs Group Inc/The 1.7     Equitable Financial Life Global Funding 1.7     Capital One Financial Corp 1.6     Wells Fargo & Co 1.6     Hyundai Capital America 1.6     JPMorgan Chase & Co 1.3       41.1
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses The fund modified its principal investment risks during the reporting period.
Material Fund Change Expenses [Text Block]	The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses
Material Fund Change Risks Change [Text Block]	The fund modified its principal investment risks during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-877-208-0098</span>" id="sjs-B268">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B269">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B270">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Sustainable Low Duration Bond Fund
Shareholder Report [Line Items]
Fund Name	Fidelity® Sustainable Low Duration Bond Fund
Class Name	Fidelity® Sustainable Low Duration Bond Fund
Trading Symbol	FAPGX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Sustainable Low Duration Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-800-544-8544
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Fidelity® Sustainable Low Duration Bond Fund $ 0.25 %
Expenses Paid, Amount	$ 26
Expense Ratio, Percent	0.25%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B287">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE April 13, 2022 through August 31, 2024. Initial investment of $10,000. Fidelity® Sustainable Low Duration Bond Fund   $10,000 $10,001   $10,404   Bloomberg US Treasury Bill: 6-9 Months Index   $10,000 $9,990   $10,301   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,696   $9,581     2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Fidelity® Sustainable Low Duration Bond Fund 5.79% 4.10% Bloomberg US Treasury Bill: 6-9 Months Index 5.37% 3.49% Bloomberg U.S. Aggregate Bond Index 7.30% 1.16% A   From April 13, 2022   Visit www.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Apr. 13, 2022
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 29,475,941
Holdings Count | shares	267
Advisory Fees Paid, Amount	$ 53,128
Investment Company Portfolio Turnover	67%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 267 Total Advisory Fee $ Portfolio Turnover 67 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 25.8 AAA 10.9 AA 1.7 A 26.7 BBB 30.6 Short-Term Investments and Net Other Assets (Liabilities) 4.3 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     Corporate Bonds 58.1 U.S. Treasury Obligations 25.8 Asset-Backed Securities 10.6 Other Investments 0.9 CMOs and Other Mortgage Related Securities 0.3 Short-Term Investments and Net Other Assets (Liabilities) 4.3 ASSET ALLOCATION (% of Fund's net assets)   United States 91.4 Canada 6.5 Netherlands 0.8 China 0.8 Germany 0.5 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Bill 25.8     General Motors Financial Co Inc 2.0     Morgan Stanley 1.9     Bank of America Corp 1.9     Goldman Sachs Group Inc/The 1.7     Equitable Financial Life Global Funding 1.7     Capital One Financial Corp 1.6     Wells Fargo & Co 1.6     Hyundai Capital America 1.6     JPMorgan Chase & Co 1.3       41.1
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-544-8544 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses The fund modified its principal investment risks during the reporting period.
Material Fund Change Expenses [Text Block]	The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses
Material Fund Change Risks Change [Text Block]	The fund modified its principal investment risks during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-544-8544 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-800-544-8544</span>" id="sjs-B303">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-800-544-8544&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B304">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B305">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M
Shareholder Report [Line Items]
Fund Name	Fidelity® Sustainable Low Duration Bond Fund
Class Name	Fidelity Advisor® Sustainable Low Duration Bond Fund Class M
Trading Symbol	FAPBX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Sustainable Low Duration Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-877-208-0098
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class M $ 0.43 %
Expenses Paid, Amount	$ 45
Expense Ratio, Percent	0.43%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B322">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE April 13, 2022 through August 31, 2024. Initial investment of $10,000 and the current sales charge was paid. Class M   $9,850 $9,845   $10,224   Bloomberg US Treasury Bill: 6-9 Months Index   $10,000 $9,990   $10,301   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,696   $9,581     2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Class M (incl. 1.50% sales charge)   4.01% 3.26% Class M (without 1.50% sales charge) 5.60% 3.92% Bloomberg US Treasury Bill: 6-9 Months Index 5.37% 3.49% Bloomberg U.S. Aggregate Bond Index 7.30% 1.16% A   From April 13, 2022   Visit institutional.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Apr. 13, 2022
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 29,475,941
Holdings Count | shares	267
Advisory Fees Paid, Amount	$ 53,128
Investment Company Portfolio Turnover	67%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 267 Total Advisory Fee $ Portfolio Turnover 67 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 25.8 AAA 10.9 AA 1.7 A 26.7 BBB 30.6 Short-Term Investments and Net Other Assets (Liabilities) 4.3 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     Corporate Bonds 58.1 U.S. Treasury Obligations 25.8 Asset-Backed Securities 10.6 Other Investments 0.9 CMOs and Other Mortgage Related Securities 0.3 Short-Term Investments and Net Other Assets (Liabilities) 4.3 ASSET ALLOCATION (% of Fund's net assets)   United States 91.4 Canada 6.5 Netherlands 0.8 China 0.8 Germany 0.5 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Bill 25.8     General Motors Financial Co Inc 2.0     Morgan Stanley 1.9     Bank of America Corp 1.9     Goldman Sachs Group Inc/The 1.7     Equitable Financial Life Global Funding 1.7     Capital One Financial Corp 1.6     Wells Fargo & Co 1.6     Hyundai Capital America 1.6     JPMorgan Chase & Co 1.3       41.1
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses The fund modified its principal investment risks during the reporting period.
Material Fund Change Expenses [Text Block]	The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses
Material Fund Change Risks Change [Text Block]	The fund modified its principal investment risks during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-877-208-0098</span>" id="sjs-B338">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B339">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B340">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C
Shareholder Report [Line Items]
Fund Name	Fidelity® Sustainable Low Duration Bond Fund
Class Name	Fidelity Advisor® Sustainable Low Duration Bond Fund Class C
Trading Symbol	FANDX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Sustainable Low Duration Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-877-208-0098
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class C $ 1.28 %
Expenses Paid, Amount	$ 131
Expense Ratio, Percent	1.28%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B357">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE April 13, 2022 through August 31, 2024. Initial investment of $10,000. Class C   $10,000 $9,957   $10,253   Bloomberg US Treasury Bill: 6-9 Months Index   $10,000 $9,990   $10,301   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,696   $9,581     2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Class C  (incl. contingent deferred sales charge) 3.71% 3.02% Class C 4.71% 3.02% Bloomberg US Treasury Bill: 6-9 Months Index 5.37% 3.49% Bloomberg U.S. Aggregate Bond Index 7.30% 1.16% A   From April 13, 2022   Visit institutional.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Apr. 13, 2022
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 29,475,941
Holdings Count | shares	267
Advisory Fees Paid, Amount	$ 53,128
Investment Company Portfolio Turnover	67%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 267 Total Advisory Fee $ Portfolio Turnover 67 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 25.8 AAA 10.9 AA 1.7 A 26.7 BBB 30.6 Short-Term Investments and Net Other Assets (Liabilities) 4.3 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     Corporate Bonds 58.1 U.S. Treasury Obligations 25.8 Asset-Backed Securities 10.6 Other Investments 0.9 CMOs and Other Mortgage Related Securities 0.3 Short-Term Investments and Net Other Assets (Liabilities) 4.3 ASSET ALLOCATION (% of Fund's net assets)   United States 91.4 Canada 6.5 Netherlands 0.8 China 0.8 Germany 0.5 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Bill 25.8     General Motors Financial Co Inc 2.0     Morgan Stanley 1.9     Bank of America Corp 1.9     Goldman Sachs Group Inc/The 1.7     Equitable Financial Life Global Funding 1.7     Capital One Financial Corp 1.6     Wells Fargo & Co 1.6     Hyundai Capital America 1.6     JPMorgan Chase & Co 1.3       41.1
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses The fund modified its principal investment risks during the reporting period.
Material Fund Change Expenses [Text Block]	The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses
Material Fund Change Risks Change [Text Block]	The fund modified its principal investment risks during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-877-208-0098</span>" id="sjs-B373">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B374">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B375">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Sustainability Bond Index Fund
Shareholder Report [Line Items]
Fund Name	Fidelity® Sustainability Bond Index Fund
Class Name	Fidelity® Sustainability Bond Index Fund
Trading Symbol	FNDSX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Sustainability Bond Index Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com.
Additional Information Phone Number	1-800-544-8544
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Fidelity® Sustainability Bond Index Fund $ 0.10 %
Expenses Paid, Amount	$ 11
Expense Ratio, Percent	0.10%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B391">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE June 19, 2018 through August 31, 2024. Initial investment of $10,000. Fidelity® Sustainability Bond Index Fund   $10,000 $10,076   $11,088   $11,813   $11,746   $10,407   $10,280   Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index   $10,000 $10,090   $11,103   $11,834   $11,805   $10,466   $10,344   Bloomberg U.S. Aggregate Bond Index   $10,000 $10,091   $11,117   $11,837   $11,827   $10,465   $10,340     2018 2019 2020 2021 2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year 5 Year Life of Fund A Fidelity® Sustainability Bond Index Fund 7.06% -0.15% 1.56% Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index 7.26% -0.01% 1.69% Bloomberg U.S. Aggregate Bond Index 7.30% -0.04% 1.69% A   From June 19, 2018   Visit www.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Jun. 19, 2018
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 458,215,582
Holdings Count | shares	2,505
Advisory Fees Paid, Amount	$ 379,383
Investment Company Portfolio Turnover	55%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 2,505 Total Advisory Fee $ Portfolio Turnover 55 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 68.9 AAA 3.6 AA 1.5 A 14.6 BBB 10.9 BB 0.5 Not Rated 0.5 QUALITY DIVERSIFICATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (0.5)%   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     U.S. Treasury Obligations 42.7 Corporate Bonds 23.7 U.S. Government Agency - Mortgage Securities 25.3 Foreign Government and Government Agency Obligations 5.1 Supranational Obligations 1.4 CMOs and Other Mortgage Related Securities 1.2 U.S. Government Agency Obligations 0.9 Asset-Backed Securities 0.2 Other Investments 0.0 ASSET ALLOCATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (0.5)% United States 92.0 Multi-national 1.5 United Kingdom 1.4 Canada 1.1 Japan 0.9 Mexico 0.3 Spain 0.3 Germany 0.3 Panama 0.3 Others 1.9 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Notes 33.1     Fannie Mae Mortgage pass-thru certificates 9.8     US Treasury Bonds 9.6     Freddie Mac Gold Pool 8.1     Ginnie Mae II Pool 4.6     Uniform Mortgage Backed Securities 1.6     Ginnie Mae I Pool 1.2     JPMorgan Chase & Co 0.9     Bank of America Corp 0.8     Freddie Mac Multiclass Mortgage participation certificates 0.7       70.4
Fidelity Series Corporate Bond Fund
Shareholder Report [Line Items]
Fund Name	Fidelity® Series Corporate Bond Fund
Class Name	Fidelity® Series Corporate Bond Fund
Trading Symbol	FHMFX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Series Corporate Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544.
Additional Information Phone Number	1-800-544-8544
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Fidelity® Series Corporate Bond Fund $ A 0.00 % B A Amount represents less than $.50 B Amount represents less than 0.005%
Expenses Paid, Amount	$ 0
Expense Ratio, Percent	0%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • • • • •
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B417">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE August 17, 2018 through August 31, 2024. Initial investment of $10,000. Fidelity® Series Corporate Bond Fund   $10,000 $9,963   $11,296   $12,221   $12,610   $10,698   $10,807   Bloomberg U.S. Credit Bond Index   $10,000 $10,005   $11,305   $12,107   $12,381   $10,594   $10,684   Bloomberg U.S. Aggregate Bond Index   $10,000 $10,014   $11,033   $11,747   $11,737   $10,386   $10,262     2018 2019 2020 2021 2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year 5 Year Life of Fund A Fidelity® Series Corporate Bond Fund 10.15% 1.05% 2.92% Bloomberg U.S. Credit Bond Index 8.98% 0.59% 2.55% Bloomberg U.S. Aggregate Bond Index 7.30% -0.04% 1.61% A   From August 17, 2018   Visit www.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Aug. 17, 2018
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 598,407,126
Holdings Count | shares	574
Advisory Fees Paid, Amount	$ 0
Investment Company Portfolio Turnover	26%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 574 Total Advisory Fee $ Portfolio Turnover 26 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 8.8 AAA 0.0 AA 0.5 A 17.8 BBB 63.2 BB 6.8 B 0.4 Not Rated 0.2 Short-Term Investments and Net Other Assets (Liabilities) 2.3 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     Corporate Bonds 88.1 U.S. Treasury Obligations 8.8 Preferred Securities 0.3 Asset-Backed Securities 0.3 Foreign Government and Government Agency Obligations 0.2 Short-Term Investments and Net Other Assets (Liabilities) 2.3 ASSET ALLOCATION (% of Fund's net assets)   United States 79.8 United Kingdom 4.1 Ireland 3.0 Canada 3.0 France 2.7 Germany 1.7 Switzerland 1.3 Spain 0.8 Italy 0.7 Others 2.9 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Bonds 8.6     Bank of America Corp 2.4     JPMorgan Chase & Co 1.5     Boeing Co 1.5     Wells Fargo & Co 1.4     Barclays PLC 1.3     UBS Group AG 1.3     Broadcom Inc 1.3     Energy Transfer LP 1.3     AerCap Ireland Capital DAC / AerCap Global Aviation Trust 1.2       21.8
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z
Shareholder Report [Line Items]
Fund Name	Fidelity® Sustainable Core Plus Bond Fund
Class Name	Fidelity Advisor® Sustainable Core Plus Bond Fund Class Z
Trading Symbol	FIAMX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Sustainable Core Plus Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-877-208-0098
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class Z $ 0.36 %
Expenses Paid, Amount	$ 37
Expense Ratio, Percent	0.36%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B445">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE April 13, 2022 through August 31, 2024. Initial investment of $10,000. Class Z   $10,000 $9,595   $9,559   Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index   $10,000 $9,703   $9,590   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,696   $9,581     2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Class Z 7.84% 1.28% Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index 7.26% 1.19% Bloomberg U.S. Aggregate Bond Index 7.30% 1.16% A   From April 13, 2022   Visit institutional.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Apr. 13, 2022
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 39,262,600
Holdings Count | shares	597
Advisory Fees Paid, Amount	$ 121,381
Investment Company Portfolio Turnover	334%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 597 Total Advisory Fee $ Portfolio Turnover 334 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 57.2 AAA 6.4 AA 1.0 A 11.6 BBB 16.3 BB 2.7 B 2.8 CCC,CC,C 1.5 Not Rated 2.1 Equities 0.0 QUALITY DIVERSIFICATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (1.6)%   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     U.S. Treasury Obligations 35.7 Corporate Bonds 35.2 U.S. Government Agency - Mortgage Securities 21.5 Asset-Backed Securities 7.5 CMOs and Other Mortgage Related Securities 0.9 Preferred Securities 0.4 Bank Loan Obligations 0.2 Foreign Government and Government Agency Obligations 0.2 Common Stocks 0.0 ASSET ALLOCATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (1.6)% United States 85.3 Grand Cayman (UK Overseas Ter) 5.1 United Kingdom 1.5 Bailiwick Of Jersey 1.3 Canada 1.2 Netherlands 0.8 Germany 0.7 Multi-national 0.6 Italy 0.5 Others 3.0 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Notes 25.0     US Treasury Bonds 10.6     Uniform Mortgage Backed Securities 10.1     Ginnie Mae II Pool 5.4     Fannie Mae Mortgage pass-thru certificates 3.2     Freddie Mac Gold Pool 2.4     Symphony Clo Xxvi Ltd / Symphony Clo Xxvi LLC 1.5     Bank of America Corp 1.4     Morgan Stanley 1.0     Citigroup Inc 0.9       61.5
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fund modified its principal investment risks during the reporting period.
Material Fund Change Risks Change [Text Block]	The fund modified its principal investment risks during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-877-208-0098</span>" id="sjs-B460">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B461">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B462">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Advisor Conservative Income Bond Fund - Class Z
Shareholder Report [Line Items]
Fund Name	Fidelity® Conservative Income Bond Fund
Class Name	Fidelity Advisor® Conservative Income Bond Fund Class Z
Trading Symbol	FCNYX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Conservative Income Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-877-208-0098
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class Z $ 0.20 %
Expenses Paid, Amount	$ 21
Expense Ratio, Percent	0.20%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • •
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B479">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE May 25, 2023 through August 31, 2024. Initial investment of $10,000. Class Z   $10,000 $10,156   Bloomberg U.S. 3-6 Month Treasury Bill Index   $10,000 $10,143   Bloomberg U.S. Aggregate Bond Index   $10,000 $10,014     2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Class Z 5.97% 5.95% Bloomberg U.S. 3-6 Month Treasury Bill Index 5.55% 5.51% Bloomberg U.S. Aggregate Bond Index 7.30% 5.81% A   From May 25, 2023   Visit institutional.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	May 25, 2023
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 6,175,559,746
Holdings Count | shares	270
Advisory Fees Paid, Amount	$ 12,538,960
Investment Company Portfolio Turnover	76%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 270 Total Advisory Fee $ Portfolio Turnover 76 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 17.0 AAA 14.4 AA 3.5 A 24.8 BBB 17.2 Short-Term Investments and Net Other Assets (Liabilities) 23.1 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     Corporate Bonds 45.3 U.S. Treasury Obligations 17.0 Asset-Backed Securities 14.4 Other Investments 0.2 Short-Term Investments and Net Other Assets (Liabilities) 23.1 ASSET ALLOCATION (% of Fund's net assets) United States 83.8 Germany 3.5 Canada 3.4 United Kingdom 3.0 Switzerland 1.4 Japan 1.2 Netherlands 1.1 Ireland 0.8 France 0.7 Others 1.1 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Bill 11.1     US Treasury Notes 5.9     Royal Bank of Canada 1.5     Toronto-Dominion Bank/NY 1.1     General Motors Financial Co Inc 1.1     HSBC USA Inc 1.1     Volkswagen Group of America Finance LLC 1.1     Barclays PLC 1.1     Athene Global Funding 1.0     Bank of Montreal 1.0       26.0
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fund's principal investment strategies were modified during the reporting period, as described in the prospectus.
Material Fund Change Strategies [Text Block]	The fund's principal investment strategies were modified during the reporting period, as described in the prospectus.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-877-208-0098</span>" id="sjs-B494">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B495">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B496">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Sustainable Core Plus Bond Fund
Shareholder Report [Line Items]
Fund Name	Fidelity® Sustainable Core Plus Bond Fund
Class Name	Fidelity® Sustainable Core Plus Bond Fund
Trading Symbol	FIAEX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Sustainable Core Plus Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-800-544-8544
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Fidelity® Sustainable Core Plus Bond Fund $ 0.45 %
Expenses Paid, Amount	$ 47
Expense Ratio, Percent	0.45%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B513">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE April 13, 2022 through August 31, 2024. Initial investment of $10,000. Fidelity® Sustainable Core Plus Bond Fund   $10,000 $9,592   $9,547   Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index   $10,000 $9,703   $9,590   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,696   $9,581     2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Fidelity® Sustainable Core Plus Bond Fund 7.63% 1.15% Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index 7.26% 1.19% Bloomberg U.S. Aggregate Bond Index 7.30% 1.16% A   From April 13, 2022   Visit www.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Apr. 13, 2022
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 39,262,600
Holdings Count | shares	597
Advisory Fees Paid, Amount	$ 121,381
Investment Company Portfolio Turnover	334%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 597 Total Advisory Fee $ Portfolio Turnover 334 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 57.2 AAA 6.4 AA 1.0 A 11.6 BBB 16.3 BB 2.7 B 2.8 CCC,CC,C 1.5 Not Rated 2.1 Equities 0.0 QUALITY DIVERSIFICATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (1.6)%   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     U.S. Treasury Obligations 35.7 Corporate Bonds 35.2 U.S. Government Agency - Mortgage Securities 21.5 Asset-Backed Securities 7.5 CMOs and Other Mortgage Related Securities 0.9 Preferred Securities 0.4 Bank Loan Obligations 0.2 Foreign Government and Government Agency Obligations 0.2 Common Stocks 0.0 ASSET ALLOCATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (1.6)% United States 85.3 Grand Cayman (UK Overseas Ter) 5.1 United Kingdom 1.5 Bailiwick Of Jersey 1.3 Canada 1.2 Netherlands 0.8 Germany 0.7 Multi-national 0.6 Italy 0.5 Others 3.0 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Notes 25.0     US Treasury Bonds 10.6     Uniform Mortgage Backed Securities 10.1     Ginnie Mae II Pool 5.4     Fannie Mae Mortgage pass-thru certificates 3.2     Freddie Mac Gold Pool 2.4     Symphony Clo Xxvi Ltd / Symphony Clo Xxvi LLC 1.5     Bank of America Corp 1.4     Morgan Stanley 1.0     Citigroup Inc 0.9       61.5
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-544-8544 or by sending an e-mail to fidfunddocuments fidelity.com . The fund modified its principal investment risks during the reporting period.
Material Fund Change Risks Change [Text Block]	The fund modified its principal investment risks during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-544-8544 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-800-544-8544</span>" id="sjs-B528">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-800-544-8544&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B529">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B530">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity SAI Sustainable Low Duration Income Fund
Shareholder Report [Line Items]
Fund Name	Fidelity® SAI Sustainable Low Duration Income Fund
Class Name	Fidelity® SAI Sustainable Low Duration Income Fund
Trading Symbol	FAPFX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® SAI Sustainable Low Duration Income Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-800-544-3455
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Fidelity® SAI Sustainable Low Duration Income Fund $ 0.20 %
Expenses Paid, Amount	$ 21
Expense Ratio, Percent	0.20%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B547">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE April 13, 2022 through August 31, 2024. Initial investment of $10,000. Fidelity® SAI Sustainable Low Duration Income Fund   $10,000 $10,009   $10,431   Bloomberg US Treasury Bill: 6-9 Months Index   $10,000 $9,990   $10,301   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,696   $9,581     2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Fidelity® SAI Sustainable Low Duration Income Fund 5.89% 4.25% Bloomberg US Treasury Bill: 6-9 Months Index 5.37% 3.49% Bloomberg U.S. Aggregate Bond Index 7.30% 1.16% A   From April 13, 2022   Visit www.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Apr. 13, 2022
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 30,341,180
Holdings Count | shares	316
Advisory Fees Paid, Amount	$ 35,389
Investment Company Portfolio Turnover	32%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 316 Total Advisory Fee $ Portfolio Turnover 32 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 29.7 AAA 7.9 AA 0.8 A 24.9 BBB 33.0 Short-Term Investments and Net Other Assets (Liabilities) 3.7 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     Corporate Bonds 58.7 U.S. Treasury Obligations 29.7 Asset-Backed Securities 7.8 CMOs and Other Mortgage Related Securities 0.1 Short-Term Investments and Net Other Assets (Liabilities) 3.7 ASSET ALLOCATION (% of Fund's net assets) United States 93.2 Canada 5.2 China 0.8 Netherlands 0.8 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Bill 29.7     JPMorgan Chase & Co 2.1     Morgan Stanley 2.0     Goldman Sachs Group Inc/The 1.8     General Motors Financial Co Inc 1.7     Bank of America Corp 1.7     Wells Fargo & Co 1.7     Hyundai Capital America 1.7     Citigroup Inc 1.7     Equitable Financial Life Global Funding 1.6       45.7
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-544-3455 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses • Expense reductions The fund's contractual management fee was reduced during the reporting period. The fund reduced its contractual expense cap during the reporting period. The fund modified its principal investment risks during the reporting period.
Material Fund Change Expenses [Text Block]	The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses • Expense reductions The fund's contractual management fee was reduced during the reporting period. The fund reduced its contractual expense cap during the reporting period.
Material Fund Change Risks Change [Text Block]	The fund modified its principal investment risks during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-544-3455 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-800-544-3455</span>" id="sjs-B563">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-800-544-3455&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B564">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B565">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M
Shareholder Report [Line Items]
Fund Name	Fidelity® Sustainable Core Plus Bond Fund
Class Name	Fidelity Advisor® Sustainable Core Plus Bond Fund Class M
Trading Symbol	FIAKX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Sustainable Core Plus Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-877-208-0098
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class M $ 0.68 %
Expenses Paid, Amount	$ 70
Expense Ratio, Percent	0.68%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • Application of FMR's environmental, social, and governance (ESG) ratings process and/or its sustainable investing exclusion criteria may affect the fund's exposure to certain issuers, sectors, regions, and countries and may affect the fund's performance.
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B582">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE April 13, 2022 through August 31, 2024. Initial investment of $10,000 and the current sales charge was paid. Class M   $9,600 $9,202   $9,139   Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index   $10,000 $9,703   $9,590   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,696   $9,581     2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Class M (incl. 4.00% sales charge)   3.09% -0.78% Class M (without 4.00% sales charge) 7.39% 0.93% Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index 7.26% 1.19% Bloomberg U.S. Aggregate Bond Index 7.30% 1.16% A   From April 13, 2022   Visit institutional.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	Apr. 13, 2022
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 39,262,600
Holdings Count | shares	597
Advisory Fees Paid, Amount	$ 121,381
Investment Company Portfolio Turnover	334%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 597 Total Advisory Fee $ Portfolio Turnover 334 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 57.2 AAA 6.4 AA 1.0 A 11.6 BBB 16.3 BB 2.7 B 2.8 CCC,CC,C 1.5 Not Rated 2.1 Equities 0.0 QUALITY DIVERSIFICATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (1.6)%   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     U.S. Treasury Obligations 35.7 Corporate Bonds 35.2 U.S. Government Agency - Mortgage Securities 21.5 Asset-Backed Securities 7.5 CMOs and Other Mortgage Related Securities 0.9 Preferred Securities 0.4 Bank Loan Obligations 0.2 Foreign Government and Government Agency Obligations 0.2 Common Stocks 0.0 ASSET ALLOCATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (1.6)% United States 85.3 Grand Cayman (UK Overseas Ter) 5.1 United Kingdom 1.5 Bailiwick Of Jersey 1.3 Canada 1.2 Netherlands 0.8 Germany 0.7 Multi-national 0.6 Italy 0.5 Others 3.0 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Notes 25.0     US Treasury Bonds 10.6     Uniform Mortgage Backed Securities 10.1     Ginnie Mae II Pool 5.4     Fannie Mae Mortgage pass-thru certificates 3.2     Freddie Mac Gold Pool 2.4     Symphony Clo Xxvi Ltd / Symphony Clo Xxvi LLC 1.5     Bank of America Corp 1.4     Morgan Stanley 1.0     Citigroup Inc 0.9       61.5
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fund modified its principal investment risks during the reporting period.
Material Fund Change Risks Change [Text Block]	The fund modified its principal investment risks during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-877-208-0098</span>" id="sjs-B597">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B598">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B599">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Conservative Income Bond Fund
Shareholder Report [Line Items]
Fund Name	Fidelity® Conservative Income Bond Fund
Class Name	Fidelity® Conservative Income Bond Fund
Trading Symbol	FCNVX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Conservative Income Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-8544 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-800-544-8544
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Fidelity® Conservative Income Bond Fund $ 0.25 %
Expenses Paid, Amount	$ 26
Expense Ratio, Percent	0.25%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • •
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B616">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the past 10 years?      CUMULATIVE PERFORMANCE August 31, 2014 through August 31, 2024. Initial investment of $10,000. Fidelity® Conservative Income Bond Fund   $10,000 $10,026   $10,120   $10,249   $10,440   $10,711   $10,912   $10,933   $10,937   $11,467   $12,133   Bloomberg U.S. 3-6 Month Treasury Bill Index   $10,000 $10,008   $10,047   $10,114   $10,264   $10,522   $10,680   $10,689   $10,719   $11,178   $11,798   Bloomberg U.S. Aggregate Bond Index   $10,000 $10,156   $10,761   $10,814   $10,701   $11,789   $12,553   $12,542   $11,098   $10,965   $11,765     2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year 5 Year 10 Year Fidelity® Conservative Income Bond Fund 5.81% 2.52% 1.95% Bloomberg U.S. 3-6 Month Treasury Bill Index 5.55% 2.32% 1.67% Bloomberg U.S. Aggregate Bond Index 7.30% -0.04% 1.64%   Visit www.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 6,175,559,746
Holdings Count | shares	270
Advisory Fees Paid, Amount	$ 12,538,960
Investment Company Portfolio Turnover	76%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 270 Total Advisory Fee $ Portfolio Turnover 76 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 17.0 AAA 14.4 AA 3.5 A 24.8 BBB 17.2 Short-Term Investments and Net Other Assets (Liabilities) 23.1 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     Corporate Bonds 45.3 U.S. Treasury Obligations 17.0 Asset-Backed Securities 14.4 Other Investments 0.2 Short-Term Investments and Net Other Assets (Liabilities) 23.1 ASSET ALLOCATION (% of Fund's net assets) United States 83.8 Germany 3.5 Canada 3.4 United Kingdom 3.0 Switzerland 1.4 Japan 1.2 Netherlands 1.1 Ireland 0.8 France 0.7 Others 1.1 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Bill 11.1     US Treasury Notes 5.9     Royal Bank of Canada 1.5     Toronto-Dominion Bank/NY 1.1     General Motors Financial Co Inc 1.1     HSBC USA Inc 1.1     Volkswagen Group of America Finance LLC 1.1     Barclays PLC 1.1     Athene Global Funding 1.0     Bank of Montreal 1.0       26.0
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-544-8544 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses • Expense reductions The fund's principal investment strategies were modified during the reporting period, as described in the prospectus.
Material Fund Change Expenses [Text Block]	The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses • Expense reductions
Material Fund Change Strategies [Text Block]	The fund's principal investment strategies were modified during the reporting period, as described in the prospectus.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-544-8544 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-800-544-8544</span>" id="sjs-B631">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-800-544-8544&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B632">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B633">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity SAI Investment Grade Securitized Fund
Shareholder Report [Line Items]
Fund Name	Fidelity® SAI Investment Grade Securitized Fund
Class Name	Fidelity® SAI Investment Grade Securitized Fund
Trading Symbol	FSMOX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® SAI Investment Grade Securitized Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-800-544-3455 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-800-544-3455
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Fidelity® SAI Investment Grade Securitized Fund $ 0.31 %
Expenses Paid, Amount	$ 33
Expense Ratio, Percent	0.31%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • • • • • •
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B650">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE May 17, 2023 through August 31, 2024. Initial investment of $10,000. Fidelity® SAI Investment Grade Securitized Fund   $10,000 $9,858   Bloomberg U.S. Securitized Index   $10,000 $9,861   Bloomberg U.S. Aggregate Bond Index   $10,000 $9,877     2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Fidelity® SAI Investment Grade Securitized Fund 7.85% 4.85% Bloomberg U.S. Securitized Index 7.55% 4.66% Bloomberg U.S. Aggregate Bond Index 7.30% 4.59% A   From May 17, 2023   Visit www.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	May 17, 2023
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 1,571,421,152
Holdings Count | shares	1,711
Advisory Fees Paid, Amount	$ 3,708,213
Investment Company Portfolio Turnover	848%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 1,711 Total Advisory Fee $ Portfolio Turnover 848 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 100.6 AAA 15.6 AA 0.5 A 0.0 CCC,CC,C 0.0 Not Rated 16.4 QUALITY DIVERSIFICATION (% of Fund's net assets)   Short-Term Investments and Net Other Assets (Liabilities) - (33.1)%   We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     U.S. Government Agency - Mortgage Securities 94.3 CMOs and Other Mortgage Related Securities 27.0 U.S. Treasury Obligations 6.3 Asset-Backed Securities 5.1 Purchased Swaptions 0.4 ASSET ALLOCATION (% of Fund's net assets) Short-Term Investments and Net Other Assets (Liabilities) - (33.1)% United States 99.9 Canada 0.1 United Kingdom 0.0 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     Fannie Mae Mortgage pass-thru certificates 32.4     Ginnie Mae II Pool 26.3     Uniform Mortgage Backed Securities 16.3     Freddie Mac Gold Pool 15.3     Freddie Mac Multiclass Mortgage participation certificates 8.4     Fannie Mae Guaranteed REMICS 4.5     US Treasury Notes 3.6     Ginnie Mae I Pool 2.9     US Treasury Bonds 2.7     Freddie Mac Non Gold Pool 1.1       113.5
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-544-3455 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses • Expense reductions The fund's contractual management fee was reduced during the reporting period.
Material Fund Change Expenses [Text Block]	The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses • Expense reductions The fund's contractual management fee was reduced during the reporting period.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-800-544-3455 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-800-544-3455</span>" id="sjs-B665">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-800-544-3455&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B666">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B667">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Advisor Conservative Income Bond Fund - Class I
Shareholder Report [Line Items]
Fund Name	Fidelity® Conservative Income Bond Fund
Class Name	Fidelity Advisor® Conservative Income Bond Fund Class I
Trading Symbol	FCNWX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Conservative Income Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-877-208-0098
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class I $ 0.25 %
Expenses Paid, Amount	$ 26
Expense Ratio, Percent	0.25%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • •
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B684">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE May 25, 2023 through August 31, 2024. Initial investment of $10,000. Class I   $10,000 $10,155   Bloomberg U.S. 3-6 Month Treasury Bill Index   $10,000 $10,143   Bloomberg U.S. Aggregate Bond Index   $10,000 $10,014     2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Class I 5.91% 5.90% Bloomberg U.S. 3-6 Month Treasury Bill Index 5.55% 5.51% Bloomberg U.S. Aggregate Bond Index 7.30% 5.81% A   From May 25, 2023   Visit institutional.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	May 25, 2023
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 6,175,559,746
Holdings Count | shares	270
Advisory Fees Paid, Amount	$ 12,538,960
Investment Company Portfolio Turnover	76%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 270 Total Advisory Fee $ Portfolio Turnover 76 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 17.0 AAA 14.4 AA 3.5 A 24.8 BBB 17.2 Short-Term Investments and Net Other Assets (Liabilities) 23.1 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     Corporate Bonds 45.3 U.S. Treasury Obligations 17.0 Asset-Backed Securities 14.4 Other Investments 0.2 Short-Term Investments and Net Other Assets (Liabilities) 23.1 ASSET ALLOCATION (% of Fund's net assets) United States 83.8 Germany 3.5 Canada 3.4 United Kingdom 3.0 Switzerland 1.4 Japan 1.2 Netherlands 1.1 Ireland 0.8 France 0.7 Others 1.1 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Bill 11.1     US Treasury Notes 5.9     Royal Bank of Canada 1.5     Toronto-Dominion Bank/NY 1.1     General Motors Financial Co Inc 1.1     HSBC USA Inc 1.1     Volkswagen Group of America Finance LLC 1.1     Barclays PLC 1.1     Athene Global Funding 1.0     Bank of Montreal 1.0       26.0
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fund's principal investment strategies were modified during the reporting period, as described in the prospectus.
Material Fund Change Strategies [Text Block]	The fund's principal investment strategies were modified during the reporting period, as described in the prospectus.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-877-208-0098</span>" id="sjs-B699">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B700">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B701">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>
Fidelity Advisor Conservative Income Bond Fund - Class A
Shareholder Report [Line Items]
Fund Name	Fidelity® Conservative Income Bond Fund
Class Name	Fidelity Advisor® Conservative Income Bond Fund Class A
Trading Symbol	FCNQX
Annual or Semi-Annual Statement [Text Block]	This annual shareholder report contains information about Fidelity® Conservative Income Bond Fund for the period September 1, 2023 to August 31, 2024.
Shareholder Report Annual or Semi-Annual	annual shareholder report
Additional Information [Text Block]	You can find additional information about the Fund at fundresearch.fidelity.com/prospectus/sec. You can also request this information by contacting us at 1-877-208-0098 or by sending an e-mail to fidfunddocuments@fidelity.com.
Material Fund Change Notice [Text Block]	This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number	1-877-208-0098
Additional Information Email	fidfunddocuments@fidelity.com
Additional Information Website	fundresearch.fidelity.com/prospectus/sec
Expenses [Text Block]	What were your Fund costs for the last year? (based on hypothetical $10,000 investment) FUND COST (PREVIOUS YEAR) Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class A $ 0.45 %
Expenses Paid, Amount	$ 46
Expense Ratio, Percent	0.45%
Factors Affecting Performance [Text Block]	What affected the Fund's performance this period? • • • • •
Performance Past Does Not Indicate Future [Text]	The Fund's past performance is not a good predictor of the Fund's future performance.</span>" id="sjs-B718">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">The Fund's past performance is not a good predictor of the Fund's future performance.&lt;/span>
Line Graph [Table Text Block]	How did the Fund perform over the life of Fund?      CUMULATIVE PERFORMANCE May 25, 2023 through August 31, 2024. Initial investment of $10,000 and the current sales charge was paid. Class A   $9,850 $9,998   Bloomberg U.S. 3-6 Month Treasury Bill Index   $10,000 $10,143   Bloomberg U.S. Aggregate Bond Index   $10,000 $10,014     2023 2024
Average Annual Return [Table Text Block]	AVERAGE ANNUAL TOTAL RETURNS:     1 Year Life of Fund A Class A (incl. 1.50% sales charge)   4.12% 4.45% Class A (without 1.50% sales charge) 5.70% 5.70% Bloomberg U.S. 3-6 Month Treasury Bill Index 5.55% 5.51% Bloomberg U.S. Aggregate Bond Index 7.30% 5.81% A   From May 25, 2023   Visit institutional.fidelity.com for more recent performance information.   The Fund's past performance is not a good predictor of the Fund's future performance.  The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Performance Inception Date	May 25, 2023
No Deduction of Taxes [Text Block]	The graph and table do not reflect the deduction of taxes that a shareholder would pay on fund distributions or redemption of fund shares.
Net Assets	$ 6,175,559,746
Holdings Count | shares	270
Advisory Fees Paid, Amount	$ 12,538,960
Investment Company Portfolio Turnover	76%
Additional Fund Statistics [Text Block]	Key Fund Statistics (as of August 31, 2024) KEY FACTS Fund Size $ Number of Holdings 270 Total Advisory Fee $ Portfolio Turnover 76 %
Holdings [Text Block]	U.S. Government and U.S. Government Agency Obligations 17.0 AAA 14.4 AA 3.5 A 24.8 BBB 17.2 Short-Term Investments and Net Other Assets (Liabilities) 23.1 QUALITY DIVERSIFICATION (% of Fund's net assets)     We have used ratings from Moody's Investors Service, Inc. Where Moody's® ratings are not available, we have used S&P® ratings. All ratings are as of the date indicated and do not reflect subsequent changes.     Corporate Bonds 45.3 U.S. Treasury Obligations 17.0 Asset-Backed Securities 14.4 Other Investments 0.2 Short-Term Investments and Net Other Assets (Liabilities) 23.1 ASSET ALLOCATION (% of Fund's net assets) United States 83.8 Germany 3.5 Canada 3.4 United Kingdom 3.0 Switzerland 1.4 Japan 1.2 Netherlands 1.1 Ireland 0.8 France 0.7 Others 1.1 GEOGRAPHIC DIVERSIFICATION (% of Fund's net assets)
Largest Holdings [Text Block]	TOP HOLDINGS (% of Fund's net assets)     US Treasury Bill 11.1     US Treasury Notes 5.9     Royal Bank of Canada 1.5     Toronto-Dominion Bank/NY 1.1     General Motors Financial Co Inc 1.1     HSBC USA Inc 1.1     Volkswagen Group of America Finance LLC 1.1     Barclays PLC 1.1     Athene Global Funding 1.0     Bank of Montreal 1.0       26.0
Material Fund Change [Text Block]	How has the Fund changed? This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com . The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses • Expense reductions The fund's principal investment strategies were modified during the reporting period, as described in the prospectus.
Material Fund Change Expenses [Text Block]	The fees associated with this class changed during the reporting year. The variations in class fees are primarily the result of the following changes: • Management fee • Operating expenses • Expense reductions
Material Fund Change Strategies [Text Block]	The fund's principal investment strategies were modified during the reporting period, as described in the prospectus.
Summary of Change Legend [Text Block]	This is a summary of certain changes to the Fund since September 1, 2023. For more complete information, you may review the Fund's next prospectus, which we expect to be available by October 30, 2024 at fundresearch.fidelity.com/prospectus/sec or upon request at 1-877-208-0098 or by sending an e-mail to fidfunddocuments fidelity.com .
Updated Prospectus Phone Number	1-877-208-0098</span>" id="sjs-B734">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">1-877-208-0098&lt;/span>
Updated Prospectus Email Address	fidfunddocuments@fidelity.com</span>" id="sjs-B735">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:normal;">fidfunddocuments@fidelity.com&lt;/span>
Updated Prospectus Web Address	fundresearch.fidelity.com/prospectus/sec</span>" id="sjs-B736">&lt;span style="font-family:'Fidelity Sans';font-size:11px;color:#000000;font-style:normal;font-weight:bold;">fundresearch.fidelity.com/prospectus/sec&lt;/span>

Shareholder Report, Line Graph

Shareholder Report, Line Graph (Details) - USD ($)

12 Months Ended

24 Months Ended

36 Months Ended

60 Months Ended

84 Months Ended

96 Months Ended

120 Months Ended

132 Months Ended

Aug. 31, 2024

Aug. 31, 2024

Aug. 31, 2024

Aug. 31, 2024

Aug. 31, 2024

Aug. 31, 2024

Aug. 31, 2024

Aug. 31, 2024

Aug. 31, 2023

Aug. 31, 2022

Aug. 31, 2021

Aug. 31, 2020

Aug. 31, 2019

Aug. 31, 2018

Aug. 31, 2017

Aug. 31, 2016

Aug. 31, 2015

Aug. 31, 2014

C000235221_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000235221_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.16%

C000235218_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000235218_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.16%

C000235232_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000235232_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.16%

C000235219_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000235219_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.16%

C000235229_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000235229_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.16%

C000242612_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000242612_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

3.65%

C000194645_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000194645_1_BBIndexMember_5YRMember

Account Value [Line Items]

Average Annual Return, Percent

(0.04%)

C000194645_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.30%

C000235233_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000235233_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.16%

C000235234_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000235234_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.16%

C000235230_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000235230_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.16%

C000235231_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000235231_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.16%

C000199795_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000199795_1_BBIndexMember_5YRMember

Account Value [Line Items]

Average Annual Return, Percent

(0.04%)

C000199795_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.69%

C000203456_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000203456_1_BBIndexMember_5YRMember

Account Value [Line Items]

Average Annual Return, Percent

(0.04%)

C000203456_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.61%

C000235220_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000235220_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.16%

C000243069_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000243069_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

5.81%

C000235217_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000235217_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.16%

C000235215_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000235215_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.16%

C000235222_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000235222_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.16%

C000098000_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000098000_1_BBIndexMember_5YRMember

Account Value [Line Items]

Average Annual Return, Percent

(0.04%)

C000098000_1_BBIndexMember_10YRMember

Account Value [Line Items]

Average Annual Return, Percent

1.64%

C000242809_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000242809_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

4.59%

C000243071_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000243071_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

5.81%

C000243070_1_BBIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.30%

C000243070_1_BBIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

5.81%

C000235221_LG_ClassMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Class I</span>" id="sjs-D149">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class I&lt;/span>

C000235221_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

$ 10,000

C000235221_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

$ 9,594

C000235221_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,553

$ 9,553

$ 9,553

$ 9,553

$ 9,553

$ 9,553

$ 9,553

$ 9,553

C000235221_LG_1_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index</span>" id="sjs-D161">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span>

C000235221_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235221_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,703

C000235221_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

9,590

9,590

$ 9,590

9,590

9,590

9,590

9,590

9,590

C000235221_LG_2_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-D173">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000235221_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235221_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,696

C000235221_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,581

9,581

$ 9,581

9,581

9,581

9,581

9,581

9,581

C000235221_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.66%

C000235221_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

1.18%

C000235221_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.26%

C000235221_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.19%

C000235218_LG_ClassMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Class C</span>" id="sjs-D197">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class C&lt;/span>

C000235218_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235218_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,559

C000235218_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,423

9,423

$ 9,423

9,423

9,423

9,423

9,423

9,423

C000235218_LG_1_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index</span>" id="sjs-D209">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span>

C000235218_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235218_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,703

C000235218_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

9,590

9,590

$ 9,590

9,590

9,590

9,590

9,590

9,590

C000235218_LG_2_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-D221">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000235218_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235218_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,696

C000235218_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,581

9,581

$ 9,581

9,581

9,581

9,581

9,581

9,581

C000235218_ClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.60%

C000235218_ClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

0.19%

C000235218_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

6.60%

C000235218_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

0.19%

C000235218_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.26%

C000235218_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.19%

C000235232_LG_ClassMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Class I</span>" id="sjs-D251">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class I&lt;/span>

C000235232_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235232_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,001

C000235232_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,404

10,404

$ 10,404

10,404

10,404

10,404

10,404

10,404

C000235232_LG_1_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg US Treasury Bill: 6-9 Months Index</span>" id="sjs-D263">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span>

C000235232_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235232_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,990

C000235232_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

10,301

10,301

$ 10,301

10,301

10,301

10,301

10,301

10,301

C000235232_LG_2_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-D275">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000235232_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235232_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,696

C000235232_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,581

9,581

$ 9,581

9,581

9,581

9,581

9,581

9,581

C000235232_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.79%

C000235232_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

4.10%

C000235232_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.37%

C000235232_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

3.49%

C000235219_LG_ClassMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Class A</span>" id="sjs-D299">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class A&lt;/span>

C000235219_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

9,600

C000235219_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,202

C000235219_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,137

9,137

$ 9,137

9,137

9,137

9,137

9,137

9,137

C000235219_LG_1_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index</span>" id="sjs-D311">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span>

C000235219_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235219_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,703

C000235219_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

9,590

9,590

$ 9,590

9,590

9,590

9,590

9,590

9,590

C000235219_LG_2_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-D323">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000235219_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235219_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,696

C000235219_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,581

9,581

$ 9,581

9,581

9,581

9,581

9,581

9,581

C000235219_ClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

3.09%

C000235219_ClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

(0.79%)

C000235219_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.38%

C000235219_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

0.92%

C000235219_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.26%

C000235219_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.19%

C000235229_LG_ClassMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Class A</span>" id="sjs-D353">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class A&lt;/span>

C000235229_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

9,850

C000235229_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,845

C000235229_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,221

10,221

$ 10,221

10,221

10,221

10,221

10,221

10,221

C000235229_LG_1_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg US Treasury Bill: 6-9 Months Index</span>" id="sjs-D365">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span>

C000235229_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235229_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,990

C000235229_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

10,301

10,301

$ 10,301

10,301

10,301

10,301

10,301

10,301

C000235229_LG_2_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-D377">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000235229_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235229_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,696

C000235229_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,581

$ 9,581

$ 9,581

9,581

9,581

9,581

9,581

9,581

C000235229_ClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

3.99%

C000235229_ClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

3.24%

C000235229_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.58%

C000235229_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

3.90%

C000235229_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.37%

C000235229_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

3.49%

C000242612_LG_ClassMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Fidelity® Series Sustainable Investment Grade Bond Fund</span>" id="sjs-C407">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® Series Sustainable Investment Grade Bond Fund&lt;/span>

C000242612_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,000

C000242612_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,778

$ 9,778

9,778

9,778

9,778

9,778

9,778

9,778

C000242612_LG_1_AdditionalIndexMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index</span>" id="sjs-C416">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span>

C000242612_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,000

C000242612_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

9,772

$ 9,772

9,772

9,772

9,772

9,772

9,772

9,772

C000242612_LG_2_AdditionalIndexMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-C425">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000242612_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,000

C000242612_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,768

$ 9,768

9,768

9,768

9,768

$ 9,768

9,768

9,768

C000242612_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.42%

C000242612_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

3.82%

C000242612_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.26%

C000242612_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

3.66%

C000194645_LG_ClassMember_8YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Fidelity® Short-Term Bond Index Fund</span>" id="sjs-G446">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® Short-Term Bond Index Fund&lt;/span>

C000194645_ClassMember_AsOf_2017Member

Account Value [Line Items]

Account Value

$ 10,000

C000194645_ClassMember_AsOf_2018Member

Account Value [Line Items]

Account Value

$ 9,969

C000194645_ClassMember_AsOf_2019Member

Account Value [Line Items]

Account Value

$ 10,565

C000194645_ClassMember_AsOf_2020Member

Account Value [Line Items]

Account Value

$ 11,052

C000194645_ClassMember_AsOf_2021Member

Account Value [Line Items]

Account Value

$ 11,073

C000194645_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,427

C000194645_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,551

C000194645_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 11,255

11,255

11,255

11,255

11,255

$ 11,255

11,255

11,255

C000194645_LG_1_AdditionalIndexMember_8YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. 1-5 Year Government/Credit Bond Index</span>" id="sjs-G473">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. 1-5 Year Government/Credit Bond Index&lt;/span>

C000194645_1_AdditionalIndexMember_AsOf_2017Member

Account Value [Line Items]

Account Value

10,000

C000194645_1_AdditionalIndexMember_AsOf_2018Member

Account Value [Line Items]

Account Value

9,990

C000194645_1_AdditionalIndexMember_AsOf_2019Member

Account Value [Line Items]

Account Value

10,586

C000194645_1_AdditionalIndexMember_AsOf_2020Member

Account Value [Line Items]

Account Value

11,086

C000194645_1_AdditionalIndexMember_AsOf_2021Member

Account Value [Line Items]

Account Value

11,122

C000194645_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,472

C000194645_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,596

C000194645_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

11,303

11,303

11,303

11,303

11,303

$ 11,303

11,303

11,303

C000194645_LG_2_AdditionalIndexMember_8YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-G500">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000194645_2_AdditionalIndexMember_AsOf_2017Member

Account Value [Line Items]

Account Value

10,000

C000194645_2_AdditionalIndexMember_AsOf_2018Member

Account Value [Line Items]

Account Value

9,938

C000194645_2_AdditionalIndexMember_AsOf_2019Member

Account Value [Line Items]

Account Value

10,949

C000194645_2_AdditionalIndexMember_AsOf_2020Member

Account Value [Line Items]

Account Value

11,658

C000194645_2_AdditionalIndexMember_AsOf_2021Member

Account Value [Line Items]

Account Value

11,648

C000194645_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,307

C000194645_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,184

C000194645_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,927

10,927

$ 10,927

$ 10,927

10,927

$ 10,927

10,927

10,927

C000194645_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

6.68%

C000194645_NoLoadClassMember_5YRMember

Account Value [Line Items]

Average Annual Return, Percent

1.27%

C000194645_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

1.74%

C000194645_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

6.67%

C000194645_0_AdditionalIndexMember_5YRMember

Account Value [Line Items]

Average Annual Return, Percent

1.32%

C000194645_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.80%

C000235233_LG_ClassMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Class Z</span>" id="sjs-D545">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class Z&lt;/span>

C000235233_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235233_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,003

C000235233_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,411

10,411

$ 10,411

$ 10,411

10,411

10,411

10,411

10,411

C000235233_LG_1_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg US Treasury Bill: 6-9 Months Index</span>" id="sjs-D557">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span>

C000235233_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235233_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,990

C000235233_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

10,301

10,301

$ 10,301

10,301

10,301

10,301

10,301

10,301

C000235233_LG_2_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-D569">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000235233_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235233_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,696

C000235233_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,581

9,581

$ 9,581

9,581

9,581

9,581

9,581

9,581

C000235233_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.84%

C000235233_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

4.15%

C000235233_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.37%

C000235233_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

3.49%

C000235234_LG_ClassMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Fidelity® Sustainable Low Duration Bond Fund</span>" id="sjs-D593">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® Sustainable Low Duration Bond Fund&lt;/span>

C000235234_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235234_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,001

C000235234_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,404

10,404

$ 10,404

10,404

10,404

10,404

10,404

10,404

C000235234_LG_1_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg US Treasury Bill: 6-9 Months Index</span>" id="sjs-D605">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span>

C000235234_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235234_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,990

C000235234_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

10,301

10,301

$ 10,301

10,301

10,301

10,301

10,301

10,301

C000235234_LG_2_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-D617">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000235234_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235234_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,696

C000235234_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,581

9,581

$ 9,581

9,581

9,581

9,581

9,581

9,581

C000235234_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.79%

C000235234_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

4.10%

C000235234_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.37%

C000235234_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

3.49%

C000235230_LG_ClassMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Class M</span>" id="sjs-D641">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class M&lt;/span>

C000235230_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

9,850

C000235230_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,845

C000235230_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,224

10,224

$ 10,224

10,224

10,224

10,224

10,224

10,224

C000235230_LG_1_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg US Treasury Bill: 6-9 Months Index</span>" id="sjs-D653">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span>

C000235230_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235230_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,990

C000235230_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

10,301

10,301

$ 10,301

10,301

10,301

10,301

10,301

10,301

C000235230_LG_2_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-D665">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000235230_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235230_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,696

C000235230_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,581

9,581

$ 9,581

9,581

9,581

9,581

9,581

9,581

C000235230_ClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

4.01%

C000235230_ClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

3.26%

C000235230_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.60%

C000235230_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

3.92%

C000235230_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.37%

C000235230_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

3.49%

C000235231_LG_ClassMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Class C</span>" id="sjs-D695">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class C&lt;/span>

C000235231_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235231_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,957

C000235231_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,253

10,253

$ 10,253

10,253

10,253

10,253

10,253

10,253

C000235231_LG_1_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg US Treasury Bill: 6-9 Months Index</span>" id="sjs-D707">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span>

C000235231_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235231_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,990

C000235231_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

10,301

10,301

$ 10,301

10,301

10,301

10,301

10,301

10,301

C000235231_LG_2_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-D719">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000235231_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235231_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,696

C000235231_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,581

9,581

$ 9,581

9,581

$ 9,581

9,581

9,581

9,581

C000235231_ClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

3.71%

C000235231_ClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

3.02%

C000235231_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

4.71%

C000235231_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

3.02%

C000235231_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.37%

C000235231_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

3.49%

C000199795_LG_ClassMember_7YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Fidelity® Sustainability Bond Index Fund</span>" id="sjs-F749">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® Sustainability Bond Index Fund&lt;/span>

C000199795_ClassMember_AsOf_2018Member

Account Value [Line Items]

Account Value

10,000

C000199795_ClassMember_AsOf_2019Member

Account Value [Line Items]

Account Value

10,076

C000199795_ClassMember_AsOf_2020Member

Account Value [Line Items]

Account Value

11,088

C000199795_ClassMember_AsOf_2021Member

Account Value [Line Items]

Account Value

11,813

C000199795_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

11,746

C000199795_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,407

C000199795_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,280

10,280

10,280

10,280

$ 10,280

10,280

10,280

10,280

C000199795_LG_1_AdditionalIndexMember_7YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index</span>" id="sjs-F773">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span>

C000199795_1_AdditionalIndexMember_AsOf_2018Member

Account Value [Line Items]

Account Value

10,000

C000199795_1_AdditionalIndexMember_AsOf_2019Member

Account Value [Line Items]

Account Value

10,090

C000199795_1_AdditionalIndexMember_AsOf_2020Member

Account Value [Line Items]

Account Value

11,103

C000199795_1_AdditionalIndexMember_AsOf_2021Member

Account Value [Line Items]

Account Value

11,834

C000199795_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

11,805

C000199795_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,466

C000199795_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

10,344

10,344

10,344

10,344

$ 10,344

10,344

10,344

10,344

C000199795_LG_2_AdditionalIndexMember_7YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-F797">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000199795_2_AdditionalIndexMember_AsOf_2018Member

Account Value [Line Items]

Account Value

10,000

C000199795_2_AdditionalIndexMember_AsOf_2019Member

Account Value [Line Items]

Account Value

10,091

C000199795_2_AdditionalIndexMember_AsOf_2020Member

Account Value [Line Items]

Account Value

11,117

C000199795_2_AdditionalIndexMember_AsOf_2021Member

Account Value [Line Items]

Account Value

11,837

C000199795_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

11,827

C000199795_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,465

C000199795_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,340

10,340

10,340

$ 10,340

$ 10,340

10,340

10,340

10,340

C000199795_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.06%

C000199795_NoLoadClassMember_5YRMember

Account Value [Line Items]

Average Annual Return, Percent

(0.15%)

C000199795_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

1.56%

C000199795_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.26%

C000199795_0_AdditionalIndexMember_5YRMember

Account Value [Line Items]

Average Annual Return, Percent

(0.01%)

C000199795_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.69%

C000203456_LG_ClassMember_7YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Fidelity® Series Corporate Bond Fund</span>" id="sjs-F839">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® Series Corporate Bond Fund&lt;/span>

C000203456_ClassMember_AsOf_2018Member

Account Value [Line Items]

Account Value

10,000

C000203456_ClassMember_AsOf_2019Member

Account Value [Line Items]

Account Value

9,963

C000203456_ClassMember_AsOf_2020Member

Account Value [Line Items]

Account Value

11,296

C000203456_ClassMember_AsOf_2021Member

Account Value [Line Items]

Account Value

12,221

C000203456_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

12,610

C000203456_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,698

C000203456_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,807

10,807

10,807

$ 10,807

$ 10,807

10,807

10,807

10,807

C000203456_LG_1_AdditionalIndexMember_7YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Credit Bond Index</span>" id="sjs-F863">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Credit Bond Index&lt;/span>

C000203456_1_AdditionalIndexMember_AsOf_2018Member

Account Value [Line Items]

Account Value

10,000

C000203456_1_AdditionalIndexMember_AsOf_2019Member

Account Value [Line Items]

Account Value

10,005

C000203456_1_AdditionalIndexMember_AsOf_2020Member

Account Value [Line Items]

Account Value

11,305

C000203456_1_AdditionalIndexMember_AsOf_2021Member

Account Value [Line Items]

Account Value

12,107

C000203456_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

12,381

C000203456_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,594

C000203456_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

10,684

10,684

10,684

10,684

$ 10,684

10,684

10,684

10,684

C000203456_LG_2_AdditionalIndexMember_7YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-F887">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000203456_2_AdditionalIndexMember_AsOf_2018Member

Account Value [Line Items]

Account Value

10,000

C000203456_2_AdditionalIndexMember_AsOf_2019Member

Account Value [Line Items]

Account Value

10,014

C000203456_2_AdditionalIndexMember_AsOf_2020Member

Account Value [Line Items]

Account Value

11,033

C000203456_2_AdditionalIndexMember_AsOf_2021Member

Account Value [Line Items]

Account Value

11,747

C000203456_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

11,737

C000203456_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,386

C000203456_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,262

10,262

$ 10,262

$ 10,262

$ 10,262

10,262

10,262

10,262

C000203456_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

10.15%

C000203456_NoLoadClassMember_5YRMember

Account Value [Line Items]

Average Annual Return, Percent

1.05%

C000203456_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

2.92%

C000203456_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

8.98%

C000203456_0_AdditionalIndexMember_5YRMember

Account Value [Line Items]

Average Annual Return, Percent

0.59%

C000203456_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

2.55%

C000235220_LG_ClassMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Class Z</span>" id="sjs-D929">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class Z&lt;/span>

C000235220_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235220_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,595

C000235220_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,559

9,559

$ 9,559

$ 9,559

9,559

9,559

9,559

9,559

C000235220_LG_1_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index</span>" id="sjs-D941">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span>

C000235220_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235220_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,703

C000235220_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

9,590

9,590

$ 9,590

9,590

9,590

9,590

9,590

9,590

C000235220_LG_2_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-D953">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000235220_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235220_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,696

C000235220_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,581

$ 9,581

$ 9,581

9,581

9,581

9,581

9,581

9,581

C000235220_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.84%

C000235220_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

1.28%

C000235220_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.26%

C000235220_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.19%

C000243069_LG_ClassMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Class Z</span>" id="sjs-C977">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class Z&lt;/span>

C000243069_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,000

C000243069_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,156

$ 10,156

10,156

10,156

10,156

10,156

10,156

10,156

C000243069_LG_1_AdditionalIndexMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. 3-6 Month Treasury Bill Index</span>" id="sjs-C986">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. 3-6 Month Treasury Bill Index&lt;/span>

C000243069_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,000

C000243069_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

10,143

$ 10,143

10,143

10,143

10,143

10,143

10,143

10,143

C000243069_LG_2_AdditionalIndexMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-C995">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000243069_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,000

C000243069_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,014

$ 10,014

$ 10,014

10,014

10,014

10,014

10,014

10,014

C000243069_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.97%

C000243069_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

5.95%

C000243069_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.55%

C000243069_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

5.51%

C000235217_LG_ClassMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Fidelity® Sustainable Core Plus Bond Fund</span>" id="sjs-D1016">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® Sustainable Core Plus Bond Fund&lt;/span>

C000235217_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235217_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,592

C000235217_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,547

9,547

$ 9,547

9,547

9,547

9,547

9,547

9,547

C000235217_LG_1_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index</span>" id="sjs-D1028">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span>

C000235217_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235217_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,703

C000235217_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

9,590

9,590

$ 9,590

9,590

9,590

9,590

9,590

9,590

C000235217_LG_2_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-D1040">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000235217_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235217_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,696

C000235217_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,581

9,581

$ 9,581

9,581

9,581

9,581

9,581

9,581

C000235217_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.63%

C000235217_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

1.15%

C000235217_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.26%

C000235217_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.19%

C000235215_LG_ClassMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Fidelity® SAI Sustainable Low Duration Income Fund</span>" id="sjs-D1064">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® SAI Sustainable Low Duration Income Fund&lt;/span>

C000235215_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235215_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,009

C000235215_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,431

10,431

$ 10,431

10,431

10,431

10,431

10,431

10,431

C000235215_LG_1_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg US Treasury Bill: 6-9 Months Index</span>" id="sjs-D1076">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg US Treasury Bill: 6-9 Months Index&lt;/span>

C000235215_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235215_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,990

C000235215_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

10,301

10,301

$ 10,301

10,301

10,301

10,301

10,301

10,301

C000235215_LG_2_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-D1088">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000235215_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235215_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,696

C000235215_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,581

9,581

$ 9,581

9,581

9,581

9,581

9,581

9,581

C000235215_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.89%

C000235215_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

4.25%

C000235215_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.37%

C000235215_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

3.49%

C000235222_LG_ClassMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Class M</span>" id="sjs-D1112">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class M&lt;/span>

C000235222_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

9,600

C000235222_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,202

C000235222_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,139

9,139

$ 9,139

9,139

9,139

9,139

9,139

9,139

C000235222_LG_1_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index</span>" id="sjs-D1124">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg MSCI U.S. Aggregate ESG Choice Bond Index&lt;/span>

C000235222_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235222_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,703

C000235222_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

9,590

9,590

$ 9,590

9,590

9,590

9,590

9,590

9,590

C000235222_LG_2_AdditionalIndexMember_3YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-D1136">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000235222_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,000

C000235222_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,696

C000235222_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,581

9,581

$ 9,581

9,581

9,581

9,581

9,581

$ 9,581

C000235222_ClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

3.09%

C000235222_ClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

(0.78%)

C000235222_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.39%

C000235222_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

0.93%

C000235222_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.26%

C000235222_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

1.19%

C000098000_LG_ClassMember_11YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Fidelity® Conservative Income Bond Fund</span>" id="sjs-I1166">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® Conservative Income Bond Fund&lt;/span>

C000098000_ClassMember_AsOf_2014Member

Account Value [Line Items]

Account Value

$ 10,000

C000098000_ClassMember_AsOf_2015Member

Account Value [Line Items]

Account Value

$ 10,026

C000098000_ClassMember_AsOf_2016Member

Account Value [Line Items]

Account Value

$ 10,120

C000098000_ClassMember_AsOf_2017Member

Account Value [Line Items]

Account Value

10,249

C000098000_ClassMember_AsOf_2018Member

Account Value [Line Items]

Account Value

10,440

C000098000_ClassMember_AsOf_2019Member

Account Value [Line Items]

Account Value

10,711

C000098000_ClassMember_AsOf_2020Member

Account Value [Line Items]

Account Value

10,912

C000098000_ClassMember_AsOf_2021Member

Account Value [Line Items]

Account Value

10,933

C000098000_ClassMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,937

C000098000_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

11,467

C000098000_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 12,133

12,133

12,133

12,133

12,133

12,133

12,133

$ 12,133

C000098000_LG_1_AdditionalIndexMember_11YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. 3-6 Month Treasury Bill Index</span>" id="sjs-I1202">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. 3-6 Month Treasury Bill Index&lt;/span>

C000098000_1_AdditionalIndexMember_AsOf_2014Member

Account Value [Line Items]

Account Value

10,000

C000098000_1_AdditionalIndexMember_AsOf_2015Member

Account Value [Line Items]

Account Value

10,008

C000098000_1_AdditionalIndexMember_AsOf_2016Member

Account Value [Line Items]

Account Value

10,047

C000098000_1_AdditionalIndexMember_AsOf_2017Member

Account Value [Line Items]

Account Value

10,114

C000098000_1_AdditionalIndexMember_AsOf_2018Member

Account Value [Line Items]

Account Value

10,264

C000098000_1_AdditionalIndexMember_AsOf_2019Member

Account Value [Line Items]

Account Value

10,522

C000098000_1_AdditionalIndexMember_AsOf_2020Member

Account Value [Line Items]

Account Value

10,680

C000098000_1_AdditionalIndexMember_AsOf_2021Member

Account Value [Line Items]

Account Value

10,689

C000098000_1_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

10,719

C000098000_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

11,178

C000098000_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

11,798

11,798

11,798

11,798

11,798

11,798

11,798

$ 11,798

C000098000_LG_2_AdditionalIndexMember_11YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-I1238">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000098000_2_AdditionalIndexMember_AsOf_2014Member

Account Value [Line Items]

Account Value

$ 10,000

C000098000_2_AdditionalIndexMember_AsOf_2015Member

Account Value [Line Items]

Account Value

$ 10,156

C000098000_2_AdditionalIndexMember_AsOf_2016Member

Account Value [Line Items]

Account Value

$ 10,761

C000098000_2_AdditionalIndexMember_AsOf_2017Member

Account Value [Line Items]

Account Value

$ 10,814

C000098000_2_AdditionalIndexMember_AsOf_2018Member

Account Value [Line Items]

Account Value

$ 10,701

C000098000_2_AdditionalIndexMember_AsOf_2019Member

Account Value [Line Items]

Account Value

$ 11,789

C000098000_2_AdditionalIndexMember_AsOf_2020Member

Account Value [Line Items]

Account Value

$ 12,553

C000098000_2_AdditionalIndexMember_AsOf_2021Member

Account Value [Line Items]

Account Value

$ 12,542

C000098000_2_AdditionalIndexMember_AsOf_2022Member

Account Value [Line Items]

Account Value

$ 11,098

C000098000_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,965

C000098000_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 11,765

$ 11,765

11,765

$ 11,765

11,765

11,765

$ 11,765

$ 11,765

C000098000_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.81%

C000098000_NoLoadClassMember_5YRMember

Account Value [Line Items]

Average Annual Return, Percent

2.52%

C000098000_NoLoadClassMember_10YRMember

Account Value [Line Items]

Average Annual Return, Percent

1.95%

C000098000_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.55%

C000098000_0_AdditionalIndexMember_5YRMember

Account Value [Line Items]

Average Annual Return, Percent

2.32%

C000098000_0_AdditionalIndexMember_10YRMember

Account Value [Line Items]

Average Annual Return, Percent

1.67%

C000242809_LG_ClassMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Fidelity® SAI Investment Grade Securitized Fund</span>" id="sjs-C1292">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Fidelity® SAI Investment Grade Securitized Fund&lt;/span>

C000242809_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,000

C000242809_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,858

$ 9,858

9,858

$ 9,858

9,858

9,858

$ 9,858

9,858

C000242809_LG_1_AdditionalIndexMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Securitized Index</span>" id="sjs-C1301">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Securitized Index&lt;/span>

C000242809_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,000

C000242809_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

9,861

$ 9,861

9,861

9,861

9,861

9,861

9,861

9,861

C000242809_LG_2_AdditionalIndexMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-C1310">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000242809_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,000

C000242809_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,877

$ 9,877

9,877

9,877

9,877

9,877

9,877

9,877

C000242809_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.85%

C000242809_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

4.85%

C000242809_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

7.55%

C000242809_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

4.66%

C000243071_LG_ClassMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Class I</span>" id="sjs-C1331">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class I&lt;/span>

C000243071_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,000

C000243071_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,155

$ 10,155

10,155

10,155

10,155

10,155

10,155

10,155

C000243071_LG_1_AdditionalIndexMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. 3-6 Month Treasury Bill Index</span>" id="sjs-C1340">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. 3-6 Month Treasury Bill Index&lt;/span>

C000243071_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,000

C000243071_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

10,143

$ 10,143

10,143

10,143

10,143

10,143

10,143

10,143

C000243071_LG_2_AdditionalIndexMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-C1349">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000243071_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,000

C000243071_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,014

$ 10,014

10,014

10,014

10,014

10,014

10,014

10,014

C000243071_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.91%

C000243071_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

5.90%

C000243071_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.55%

C000243071_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

5.51%

C000243070_LG_ClassMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Class A</span>" id="sjs-C1370">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Class A&lt;/span>

C000243070_ClassMember_AsOf_2023Member

Account Value [Line Items]

Account Value

9,850

C000243070_ClassMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 9,998

$ 9,998

9,998

9,998

9,998

9,998

9,998

9,998

C000243070_LG_1_AdditionalIndexMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. 3-6 Month Treasury Bill Index</span>" id="sjs-C1379">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. 3-6 Month Treasury Bill Index&lt;/span>

C000243070_1_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

10,000

C000243070_1_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

10,143

$ 10,143

10,143

10,143

10,143

10,143

10,143

10,143

C000243070_LG_2_AdditionalIndexMember_2YRMember

Account Value [Line Items]

Line Graph and Table Measure Name

Bloomberg U.S. Aggregate Bond Index</span>" id="sjs-C1388">&lt;span style="font-family:'Fidelity Sans';font-size:9px;color:#000000;font-style:normal;font-weight:normal;">Bloomberg U.S. Aggregate Bond Index&lt;/span>

C000243070_2_AdditionalIndexMember_AsOf_2023Member

Account Value [Line Items]

Account Value

$ 10,000

C000243070_2_AdditionalIndexMember_AsOf_2024Member

Account Value [Line Items]

Account Value

$ 10,014

$ 10,014

$ 10,014

$ 10,014

$ 10,014

$ 10,014

$ 10,014

$ 10,014

C000243070_ClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

4.12%

C000243070_ClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

4.45%

C000243070_NoLoadClassMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.70%

C000243070_NoLoadClassMember_2023-09-01_2024-08-31Member

Account Value [Line Items]

Average Annual Return, Percent

5.70%

C000243070_0_AdditionalIndexMember_1YRMember

Account Value [Line Items]

Average Annual Return, Percent

5.55%

C000243070_0_AdditionalIndexMember_LOCMember

Account Value [Line Items]

Average Annual Return, Percent

5.51%

Shareholder Report, Holdings (D

Shareholder Report, Holdings (Details)	Aug. 31, 2024
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	25%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	10.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	10.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	5.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	3.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	2.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	57.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	6.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	11.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	16.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | QDBBMember
Holdings [Line Items]
Percent of Net Asset Value	2.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | QDBMember
Holdings [Line Items]
Percent of Net Asset Value	2.80%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | QDCCCCCCMember
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | QDNotRatedMember
Holdings [Line Items]
Percent of Net Asset Value	2.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | QDEquitiesMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | United States
Holdings [Line Items]
Percent of Net Asset Value	85.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | GrandCaymanUKOverseasTerMember
Holdings [Line Items]
Percent of Net Asset Value	5.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | BailiwickOfJerseyMember
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | Canada
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | MultinationalMember
Holdings [Line Items]
Percent of Net Asset Value	0.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | Italy
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | OtherMember
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	35.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	35.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | AAUSGovernmentAgencyMortgageSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	21.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	7.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | AAPreferredSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | AABankLoanObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | AAForeignGovernmentandGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class I | AACommonStocksMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	25%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	10.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	10.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	5.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	3.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	2.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	57.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	6.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	11.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	16.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | QDBBMember
Holdings [Line Items]
Percent of Net Asset Value	2.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | QDBMember
Holdings [Line Items]
Percent of Net Asset Value	2.80%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | QDCCCCCCMember
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | QDNotRatedMember
Holdings [Line Items]
Percent of Net Asset Value	2.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | QDEquitiesMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | United States
Holdings [Line Items]
Percent of Net Asset Value	85.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | GrandCaymanUKOverseasTerMember
Holdings [Line Items]
Percent of Net Asset Value	5.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | BailiwickOfJerseyMember
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | Canada
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | MultinationalMember
Holdings [Line Items]
Percent of Net Asset Value	0.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | Italy
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | OtherMember
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	35.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	35.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | AAUSGovernmentAgencyMortgageSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	21.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	7.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | AAPreferredSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | AABankLoanObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | AAForeignGovernmentandGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class C | AACommonStocksMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	2%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	10.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	26.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	30.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	4.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | United States
Holdings [Line Items]
Percent of Net Asset Value	91.40%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | Canada
Holdings [Line Items]
Percent of Net Asset Value	6.50%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | China
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	58.10%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	10.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | AAOtherInvestmentsMember
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class I | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	4.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	25%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	10.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	10.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	5.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	3.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	2.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	57.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	6.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	11.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	16.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | QDBBMember
Holdings [Line Items]
Percent of Net Asset Value	2.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | QDBMember
Holdings [Line Items]
Percent of Net Asset Value	2.80%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | QDCCCCCCMember
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | QDNotRatedMember
Holdings [Line Items]
Percent of Net Asset Value	2.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | QDEquitiesMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | United States
Holdings [Line Items]
Percent of Net Asset Value	85.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | GrandCaymanUKOverseasTerMember
Holdings [Line Items]
Percent of Net Asset Value	5.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | BailiwickOfJerseyMember
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | Canada
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | MultinationalMember
Holdings [Line Items]
Percent of Net Asset Value	0.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | Italy
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | OtherMember
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	35.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	35.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | AAUSGovernmentAgencyMortgageSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	21.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	7.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | AAPreferredSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | AABankLoanObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | AAForeignGovernmentandGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class A | AACommonStocksMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	2%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	10.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	26.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	30.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	4.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | United States
Holdings [Line Items]
Percent of Net Asset Value	91.40%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | Canada
Holdings [Line Items]
Percent of Net Asset Value	6.50%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | China
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	58.10%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	10.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | AAOtherInvestmentsMember
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class A | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	4.30%
Fidelity Series Sustainable Investment Grade Bond Fund | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	32.50%
Fidelity Series Sustainable Investment Grade Bond Fund | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	11.30%
Fidelity Series Sustainable Investment Grade Bond Fund | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	9.30%
Fidelity Series Sustainable Investment Grade Bond Fund | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	5.10%
Fidelity Series Sustainable Investment Grade Bond Fund | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	4.90%
Fidelity Series Sustainable Investment Grade Bond Fund | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	3.10%
Fidelity Series Sustainable Investment Grade Bond Fund | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Series Sustainable Investment Grade Bond Fund | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Series Sustainable Investment Grade Bond Fund | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Series Sustainable Investment Grade Bond Fund | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Series Sustainable Investment Grade Bond Fund | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	66.70%
Fidelity Series Sustainable Investment Grade Bond Fund | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	3.10%
Fidelity Series Sustainable Investment Grade Bond Fund | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Series Sustainable Investment Grade Bond Fund | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	10.40%
Fidelity Series Sustainable Investment Grade Bond Fund | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	13%
Fidelity Series Sustainable Investment Grade Bond Fund | QDBBMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Series Sustainable Investment Grade Bond Fund | QDNotRatedMember
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Series Sustainable Investment Grade Bond Fund | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	2.80%
Fidelity Series Sustainable Investment Grade Bond Fund | United States
Holdings [Line Items]
Percent of Net Asset Value	92.50%
Fidelity Series Sustainable Investment Grade Bond Fund | GrandCaymanUKOverseasTerMember
Holdings [Line Items]
Percent of Net Asset Value	6.10%
Fidelity Series Sustainable Investment Grade Bond Fund | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Series Sustainable Investment Grade Bond Fund | Canada
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Series Sustainable Investment Grade Bond Fund | China
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Fidelity Series Sustainable Investment Grade Bond Fund | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	44.90%
Fidelity Series Sustainable Investment Grade Bond Fund | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	24.40%
Fidelity Series Sustainable Investment Grade Bond Fund | AAUSGovernmentAgencyMortgageSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	21.80%
Fidelity Series Sustainable Investment Grade Bond Fund | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	6.10%
Fidelity Series Sustainable Investment Grade Bond Fund | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	2.80%
Fidelity Short-Term Bond Index Fund | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	65.30%
Fidelity Short-Term Bond Index Fund | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Short-Term Bond Index Fund | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Short-Term Bond Index Fund | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Short-Term Bond Index Fund | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Short-Term Bond Index Fund | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Short-Term Bond Index Fund | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Short-Term Bond Index Fund | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	0.60%
Fidelity Short-Term Bond Index Fund | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	0.60%
Fidelity Short-Term Bond Index Fund | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Short-Term Bond Index Fund | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	67.50%
Fidelity Short-Term Bond Index Fund | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	3.30%
Fidelity Short-Term Bond Index Fund | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	2.90%
Fidelity Short-Term Bond Index Fund | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	13.40%
Fidelity Short-Term Bond Index Fund | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	12.20%
Fidelity Short-Term Bond Index Fund | QDBBMember
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Short-Term Bond Index Fund | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Short-Term Bond Index Fund | United States
Holdings [Line Items]
Percent of Net Asset Value	90.50%
Fidelity Short-Term Bond Index Fund | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Short-Term Bond Index Fund | Canada
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Short-Term Bond Index Fund | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.60%
Fidelity Short-Term Bond Index Fund | MultinationalMember
Holdings [Line Items]
Percent of Net Asset Value	2.10%
Fidelity Short-Term Bond Index Fund | OtherMember
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Short-Term Bond Index Fund | Japan
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Short-Term Bond Index Fund | Australia
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Fidelity Short-Term Bond Index Fund | Spain
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Short-Term Bond Index Fund | Ireland
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Short-Term Bond Index Fund | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	65.30%
Fidelity Short-Term Bond Index Fund | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	28.70%
Fidelity Short-Term Bond Index Fund | AAForeignGovernmentandGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Short-Term Bond Index Fund | AAOtherInvestmentsMember
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Short-Term Bond Index Fund | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Short-Term Bond Index Fund | AAUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	2.20%
Fidelity Short-Term Bond Index Fund | AASupranationalObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	2%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	2%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	10.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	26.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	30.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	4.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | United States
Holdings [Line Items]
Percent of Net Asset Value	91.40%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | Canada
Holdings [Line Items]
Percent of Net Asset Value	6.50%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | China
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	58.10%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	10.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | AAOtherInvestmentsMember
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class Z | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	4.30%
Fidelity Sustainable Low Duration Bond Fund | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Sustainable Low Duration Bond Fund | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	2%
Fidelity Sustainable Low Duration Bond Fund | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Fidelity Sustainable Low Duration Bond Fund | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Fidelity Sustainable Low Duration Bond Fund | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Sustainable Low Duration Bond Fund | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Sustainable Low Duration Bond Fund | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Sustainable Low Duration Bond Fund | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Sustainable Low Duration Bond Fund | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Sustainable Low Duration Bond Fund | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Sustainable Low Duration Bond Fund | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Sustainable Low Duration Bond Fund | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	10.90%
Fidelity Sustainable Low Duration Bond Fund | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Sustainable Low Duration Bond Fund | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	26.70%
Fidelity Sustainable Low Duration Bond Fund | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	30.60%
Fidelity Sustainable Low Duration Bond Fund | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	4.30%
Fidelity Sustainable Low Duration Bond Fund | United States
Holdings [Line Items]
Percent of Net Asset Value	91.40%
Fidelity Sustainable Low Duration Bond Fund | Canada
Holdings [Line Items]
Percent of Net Asset Value	6.50%
Fidelity Sustainable Low Duration Bond Fund | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Sustainable Low Duration Bond Fund | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Sustainable Low Duration Bond Fund | China
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Sustainable Low Duration Bond Fund | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Sustainable Low Duration Bond Fund | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	58.10%
Fidelity Sustainable Low Duration Bond Fund | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	10.60%
Fidelity Sustainable Low Duration Bond Fund | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Sustainable Low Duration Bond Fund | AAOtherInvestmentsMember
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Sustainable Low Duration Bond Fund | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	4.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	2%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	10.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	26.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	30.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	4.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | United States
Holdings [Line Items]
Percent of Net Asset Value	91.40%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | Canada
Holdings [Line Items]
Percent of Net Asset Value	6.50%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | China
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	58.10%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	10.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | AAOtherInvestmentsMember
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class M | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	4.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	2%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	10.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	26.70%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	30.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	4.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | United States
Holdings [Line Items]
Percent of Net Asset Value	91.40%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | Canada
Holdings [Line Items]
Percent of Net Asset Value	6.50%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | China
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	25.80%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	58.10%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	10.60%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | AAOtherInvestmentsMember
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Low Duration Bond Fund - Class C | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	4.30%
Fidelity Sustainability Bond Index Fund | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	33.10%
Fidelity Sustainability Bond Index Fund | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	9.80%
Fidelity Sustainability Bond Index Fund | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	9.60%
Fidelity Sustainability Bond Index Fund | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	8.10%
Fidelity Sustainability Bond Index Fund | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	4.60%
Fidelity Sustainability Bond Index Fund | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity Sustainability Bond Index Fund | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Sustainability Bond Index Fund | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Sustainability Bond Index Fund | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Sustainability Bond Index Fund | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Sustainability Bond Index Fund | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	68.90%
Fidelity Sustainability Bond Index Fund | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	3.60%
Fidelity Sustainability Bond Index Fund | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Sustainability Bond Index Fund | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	14.60%
Fidelity Sustainability Bond Index Fund | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	10.90%
Fidelity Sustainability Bond Index Fund | QDBBMember
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Sustainability Bond Index Fund | QDNotRatedMember
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Sustainability Bond Index Fund | United States
Holdings [Line Items]
Percent of Net Asset Value	92%
Fidelity Sustainability Bond Index Fund | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Sustainability Bond Index Fund | Canada
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Sustainability Bond Index Fund | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Sustainability Bond Index Fund | MultinationalMember
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Sustainability Bond Index Fund | OtherMember
Holdings [Line Items]
Percent of Net Asset Value	1.90%
Fidelity Sustainability Bond Index Fund | Japan
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Sustainability Bond Index Fund | Spain
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Sustainability Bond Index Fund | Mexico
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Sustainability Bond Index Fund | Panama
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Sustainability Bond Index Fund | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	42.70%
Fidelity Sustainability Bond Index Fund | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	23.70%
Fidelity Sustainability Bond Index Fund | AAUSGovernmentAgencyMortgageSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	25.30%
Fidelity Sustainability Bond Index Fund | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Sustainability Bond Index Fund | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Sustainability Bond Index Fund | AAForeignGovernmentandGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	5.10%
Fidelity Sustainability Bond Index Fund | AAOtherInvestmentsMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity Sustainability Bond Index Fund | AAUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Sustainability Bond Index Fund | AASupranationalObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Series Corporate Bond Fund | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	8.60%
Fidelity Series Corporate Bond Fund | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	2.40%
Fidelity Series Corporate Bond Fund | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Series Corporate Bond Fund | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Series Corporate Bond Fund | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Series Corporate Bond Fund | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Series Corporate Bond Fund | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Series Corporate Bond Fund | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Series Corporate Bond Fund | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Series Corporate Bond Fund | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Series Corporate Bond Fund | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	8.80%
Fidelity Series Corporate Bond Fund | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity Series Corporate Bond Fund | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Series Corporate Bond Fund | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	17.80%
Fidelity Series Corporate Bond Fund | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	63.20%
Fidelity Series Corporate Bond Fund | QDBBMember
Holdings [Line Items]
Percent of Net Asset Value	6.80%
Fidelity Series Corporate Bond Fund | QDBMember
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Fidelity Series Corporate Bond Fund | QDNotRatedMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Series Corporate Bond Fund | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	2.30%
Fidelity Series Corporate Bond Fund | United States
Holdings [Line Items]
Percent of Net Asset Value	79.80%
Fidelity Series Corporate Bond Fund | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	4.10%
Fidelity Series Corporate Bond Fund | Canada
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Series Corporate Bond Fund | Germany
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity Series Corporate Bond Fund | Italy
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Series Corporate Bond Fund | OtherMember
Holdings [Line Items]
Percent of Net Asset Value	2.90%
Fidelity Series Corporate Bond Fund | Spain
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Series Corporate Bond Fund | Ireland
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Series Corporate Bond Fund | France
Holdings [Line Items]
Percent of Net Asset Value	2.70%
Fidelity Series Corporate Bond Fund | Switzerland
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Series Corporate Bond Fund | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	8.80%
Fidelity Series Corporate Bond Fund | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	88.10%
Fidelity Series Corporate Bond Fund | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Series Corporate Bond Fund | AAPreferredSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.30%
Fidelity Series Corporate Bond Fund | AAForeignGovernmentandGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Series Corporate Bond Fund | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	2.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	25%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	10.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	10.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	5.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	3.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	2.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	57.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	6.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	11.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	16.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | QDBBMember
Holdings [Line Items]
Percent of Net Asset Value	2.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | QDBMember
Holdings [Line Items]
Percent of Net Asset Value	2.80%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | QDCCCCCCMember
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | QDNotRatedMember
Holdings [Line Items]
Percent of Net Asset Value	2.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | QDEquitiesMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | United States
Holdings [Line Items]
Percent of Net Asset Value	85.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | GrandCaymanUKOverseasTerMember
Holdings [Line Items]
Percent of Net Asset Value	5.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | BailiwickOfJerseyMember
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | Canada
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | MultinationalMember
Holdings [Line Items]
Percent of Net Asset Value	0.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | Italy
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | OtherMember
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	35.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	35.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | AAUSGovernmentAgencyMortgageSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	21.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	7.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | AAPreferredSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | AABankLoanObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | AAForeignGovernmentandGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class Z | AACommonStocksMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity Advisor Conservative Income Bond Fund - Class Z | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	11.10%
Fidelity Advisor Conservative Income Bond Fund - Class Z | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	5.90%
Fidelity Advisor Conservative Income Bond Fund - Class Z | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Conservative Income Bond Fund - Class Z | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class Z | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class Z | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class Z | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class Z | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class Z | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Conservative Income Bond Fund - Class Z | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Conservative Income Bond Fund - Class Z | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	17%
Fidelity Advisor Conservative Income Bond Fund - Class Z | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	14.40%
Fidelity Advisor Conservative Income Bond Fund - Class Z | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	3.50%
Fidelity Advisor Conservative Income Bond Fund - Class Z | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	24.80%
Fidelity Advisor Conservative Income Bond Fund - Class Z | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	17.20%
Fidelity Advisor Conservative Income Bond Fund - Class Z | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	23.10%
Fidelity Advisor Conservative Income Bond Fund - Class Z | United States
Holdings [Line Items]
Percent of Net Asset Value	83.80%
Fidelity Advisor Conservative Income Bond Fund - Class Z | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Advisor Conservative Income Bond Fund - Class Z | Canada
Holdings [Line Items]
Percent of Net Asset Value	3.40%
Fidelity Advisor Conservative Income Bond Fund - Class Z | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class Z | Germany
Holdings [Line Items]
Percent of Net Asset Value	3.50%
Fidelity Advisor Conservative Income Bond Fund - Class Z | OtherMember
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class Z | Japan
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Advisor Conservative Income Bond Fund - Class Z | Ireland
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Conservative Income Bond Fund - Class Z | France
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Advisor Conservative Income Bond Fund - Class Z | Switzerland
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Advisor Conservative Income Bond Fund - Class Z | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	17%
Fidelity Advisor Conservative Income Bond Fund - Class Z | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	45.30%
Fidelity Advisor Conservative Income Bond Fund - Class Z | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	14.40%
Fidelity Advisor Conservative Income Bond Fund - Class Z | AAOtherInvestmentsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Advisor Conservative Income Bond Fund - Class Z | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	23.10%
Fidelity Sustainable Core Plus Bond Fund | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	25%
Fidelity Sustainable Core Plus Bond Fund | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	10.60%
Fidelity Sustainable Core Plus Bond Fund | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	10.10%
Fidelity Sustainable Core Plus Bond Fund | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	5.40%
Fidelity Sustainable Core Plus Bond Fund | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	3.20%
Fidelity Sustainable Core Plus Bond Fund | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	2.40%
Fidelity Sustainable Core Plus Bond Fund | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Sustainable Core Plus Bond Fund | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Sustainable Core Plus Bond Fund | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Sustainable Core Plus Bond Fund | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Sustainable Core Plus Bond Fund | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	57.20%
Fidelity Sustainable Core Plus Bond Fund | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	6.40%
Fidelity Sustainable Core Plus Bond Fund | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Sustainable Core Plus Bond Fund | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	11.60%
Fidelity Sustainable Core Plus Bond Fund | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	16.30%
Fidelity Sustainable Core Plus Bond Fund | QDBBMember
Holdings [Line Items]
Percent of Net Asset Value	2.70%
Fidelity Sustainable Core Plus Bond Fund | QDBMember
Holdings [Line Items]
Percent of Net Asset Value	2.80%
Fidelity Sustainable Core Plus Bond Fund | QDCCCCCCMember
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Sustainable Core Plus Bond Fund | QDNotRatedMember
Holdings [Line Items]
Percent of Net Asset Value	2.10%
Fidelity Sustainable Core Plus Bond Fund | QDEquitiesMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity Sustainable Core Plus Bond Fund | United States
Holdings [Line Items]
Percent of Net Asset Value	85.30%
Fidelity Sustainable Core Plus Bond Fund | GrandCaymanUKOverseasTerMember
Holdings [Line Items]
Percent of Net Asset Value	5.10%
Fidelity Sustainable Core Plus Bond Fund | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Sustainable Core Plus Bond Fund | BailiwickOfJerseyMember
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Sustainable Core Plus Bond Fund | Canada
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Sustainable Core Plus Bond Fund | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Sustainable Core Plus Bond Fund | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Sustainable Core Plus Bond Fund | MultinationalMember
Holdings [Line Items]
Percent of Net Asset Value	0.60%
Fidelity Sustainable Core Plus Bond Fund | Italy
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Sustainable Core Plus Bond Fund | OtherMember
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Sustainable Core Plus Bond Fund | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	35.70%
Fidelity Sustainable Core Plus Bond Fund | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	35.20%
Fidelity Sustainable Core Plus Bond Fund | AAUSGovernmentAgencyMortgageSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	21.50%
Fidelity Sustainable Core Plus Bond Fund | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	7.50%
Fidelity Sustainable Core Plus Bond Fund | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Sustainable Core Plus Bond Fund | AAPreferredSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Fidelity Sustainable Core Plus Bond Fund | AABankLoanObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Sustainable Core Plus Bond Fund | AAForeignGovernmentandGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Sustainable Core Plus Bond Fund | AACommonStocksMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity SAI Sustainable Low Duration Income Fund | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	29.70%
Fidelity SAI Sustainable Low Duration Income Fund | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	2.10%
Fidelity SAI Sustainable Low Duration Income Fund | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	2%
Fidelity SAI Sustainable Low Duration Income Fund | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	1.80%
Fidelity SAI Sustainable Low Duration Income Fund | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity SAI Sustainable Low Duration Income Fund | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity SAI Sustainable Low Duration Income Fund | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity SAI Sustainable Low Duration Income Fund | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity SAI Sustainable Low Duration Income Fund | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1.70%
Fidelity SAI Sustainable Low Duration Income Fund | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1.60%
Fidelity SAI Sustainable Low Duration Income Fund | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	29.70%
Fidelity SAI Sustainable Low Duration Income Fund | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	7.90%
Fidelity SAI Sustainable Low Duration Income Fund | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity SAI Sustainable Low Duration Income Fund | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	24.90%
Fidelity SAI Sustainable Low Duration Income Fund | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	33%
Fidelity SAI Sustainable Low Duration Income Fund | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	3.70%
Fidelity SAI Sustainable Low Duration Income Fund | United States
Holdings [Line Items]
Percent of Net Asset Value	93.20%
Fidelity SAI Sustainable Low Duration Income Fund | Canada
Holdings [Line Items]
Percent of Net Asset Value	5.20%
Fidelity SAI Sustainable Low Duration Income Fund | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity SAI Sustainable Low Duration Income Fund | China
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity SAI Sustainable Low Duration Income Fund | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	29.70%
Fidelity SAI Sustainable Low Duration Income Fund | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	58.70%
Fidelity SAI Sustainable Low Duration Income Fund | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	7.80%
Fidelity SAI Sustainable Low Duration Income Fund | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.10%
Fidelity SAI Sustainable Low Duration Income Fund | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	3.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	25%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	10.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	10.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	5.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	3.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	2.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	57.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	6.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	11.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	16.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | QDBBMember
Holdings [Line Items]
Percent of Net Asset Value	2.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | QDBMember
Holdings [Line Items]
Percent of Net Asset Value	2.80%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | QDCCCCCCMember
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | QDNotRatedMember
Holdings [Line Items]
Percent of Net Asset Value	2.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | QDEquitiesMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | United States
Holdings [Line Items]
Percent of Net Asset Value	85.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | GrandCaymanUKOverseasTerMember
Holdings [Line Items]
Percent of Net Asset Value	5.10%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | BailiwickOfJerseyMember
Holdings [Line Items]
Percent of Net Asset Value	1.30%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | Canada
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | Germany
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | MultinationalMember
Holdings [Line Items]
Percent of Net Asset Value	0.60%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | Italy
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | OtherMember
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	35.70%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	35.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | AAUSGovernmentAgencyMortgageSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	21.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	7.50%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.90%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | AAPreferredSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | AABankLoanObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | AAForeignGovernmentandGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Advisor Sustainable Core Plus Bond Fund - Class M | AACommonStocksMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity Conservative Income Bond Fund | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	11.10%
Fidelity Conservative Income Bond Fund | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	5.90%
Fidelity Conservative Income Bond Fund | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Conservative Income Bond Fund | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Conservative Income Bond Fund | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Conservative Income Bond Fund | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Conservative Income Bond Fund | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Conservative Income Bond Fund | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Conservative Income Bond Fund | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Conservative Income Bond Fund | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Conservative Income Bond Fund | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	17%
Fidelity Conservative Income Bond Fund | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	14.40%
Fidelity Conservative Income Bond Fund | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	3.50%
Fidelity Conservative Income Bond Fund | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	24.80%
Fidelity Conservative Income Bond Fund | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	17.20%
Fidelity Conservative Income Bond Fund | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	23.10%
Fidelity Conservative Income Bond Fund | United States
Holdings [Line Items]
Percent of Net Asset Value	83.80%
Fidelity Conservative Income Bond Fund | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Conservative Income Bond Fund | Canada
Holdings [Line Items]
Percent of Net Asset Value	3.40%
Fidelity Conservative Income Bond Fund | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Conservative Income Bond Fund | Germany
Holdings [Line Items]
Percent of Net Asset Value	3.50%
Fidelity Conservative Income Bond Fund | OtherMember
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Conservative Income Bond Fund | Japan
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Conservative Income Bond Fund | Ireland
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Conservative Income Bond Fund | France
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Conservative Income Bond Fund | Switzerland
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Conservative Income Bond Fund | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	17%
Fidelity Conservative Income Bond Fund | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	45.30%
Fidelity Conservative Income Bond Fund | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	14.40%
Fidelity Conservative Income Bond Fund | AAOtherInvestmentsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Conservative Income Bond Fund | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	23.10%
Fidelity SAI Investment Grade Securitized Fund | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	32.40%
Fidelity SAI Investment Grade Securitized Fund | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	26.30%
Fidelity SAI Investment Grade Securitized Fund | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	16.30%
Fidelity SAI Investment Grade Securitized Fund | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	15.30%
Fidelity SAI Investment Grade Securitized Fund | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	8.40%
Fidelity SAI Investment Grade Securitized Fund | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	4.50%
Fidelity SAI Investment Grade Securitized Fund | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	3.60%
Fidelity SAI Investment Grade Securitized Fund | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	2.90%
Fidelity SAI Investment Grade Securitized Fund | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	2.70%
Fidelity SAI Investment Grade Securitized Fund | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity SAI Investment Grade Securitized Fund | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	100.60%
Fidelity SAI Investment Grade Securitized Fund | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	15.60%
Fidelity SAI Investment Grade Securitized Fund | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	0.50%
Fidelity SAI Investment Grade Securitized Fund | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity SAI Investment Grade Securitized Fund | QDCCCCCCMember
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity SAI Investment Grade Securitized Fund | QDNotRatedMember
Holdings [Line Items]
Percent of Net Asset Value	16.40%
Fidelity SAI Investment Grade Securitized Fund | United States
Holdings [Line Items]
Percent of Net Asset Value	99.90%
Fidelity SAI Investment Grade Securitized Fund | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	0%
Fidelity SAI Investment Grade Securitized Fund | Canada
Holdings [Line Items]
Percent of Net Asset Value	0.10%
Fidelity SAI Investment Grade Securitized Fund | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	6.30%
Fidelity SAI Investment Grade Securitized Fund | AAUSGovernmentAgencyMortgageSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	94.30%
Fidelity SAI Investment Grade Securitized Fund | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	5.10%
Fidelity SAI Investment Grade Securitized Fund | AACMOsandOtherMortgageRelatedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	27%
Fidelity SAI Investment Grade Securitized Fund | AAPurchasedSwaptionsMember
Holdings [Line Items]
Percent of Net Asset Value	0.40%
Fidelity Advisor Conservative Income Bond Fund - Class I | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	11.10%
Fidelity Advisor Conservative Income Bond Fund - Class I | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	5.90%
Fidelity Advisor Conservative Income Bond Fund - Class I | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Conservative Income Bond Fund - Class I | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class I | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class I | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class I | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class I | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class I | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Conservative Income Bond Fund - Class I | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Conservative Income Bond Fund - Class I | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	17%
Fidelity Advisor Conservative Income Bond Fund - Class I | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	14.40%
Fidelity Advisor Conservative Income Bond Fund - Class I | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	3.50%
Fidelity Advisor Conservative Income Bond Fund - Class I | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	24.80%
Fidelity Advisor Conservative Income Bond Fund - Class I | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	17.20%
Fidelity Advisor Conservative Income Bond Fund - Class I | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	23.10%
Fidelity Advisor Conservative Income Bond Fund - Class I | United States
Holdings [Line Items]
Percent of Net Asset Value	83.80%
Fidelity Advisor Conservative Income Bond Fund - Class I | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Advisor Conservative Income Bond Fund - Class I | Canada
Holdings [Line Items]
Percent of Net Asset Value	3.40%
Fidelity Advisor Conservative Income Bond Fund - Class I | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class I | Germany
Holdings [Line Items]
Percent of Net Asset Value	3.50%
Fidelity Advisor Conservative Income Bond Fund - Class I | OtherMember
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class I | Japan
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Advisor Conservative Income Bond Fund - Class I | Ireland
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Conservative Income Bond Fund - Class I | France
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Advisor Conservative Income Bond Fund - Class I | Switzerland
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Advisor Conservative Income Bond Fund - Class I | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	17%
Fidelity Advisor Conservative Income Bond Fund - Class I | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	45.30%
Fidelity Advisor Conservative Income Bond Fund - Class I | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	14.40%
Fidelity Advisor Conservative Income Bond Fund - Class I | AAOtherInvestmentsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Advisor Conservative Income Bond Fund - Class I | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	23.10%
Fidelity Advisor Conservative Income Bond Fund - Class A | TH0Member
Holdings [Line Items]
Percent of Net Asset Value	11.10%
Fidelity Advisor Conservative Income Bond Fund - Class A | TH1Member
Holdings [Line Items]
Percent of Net Asset Value	5.90%
Fidelity Advisor Conservative Income Bond Fund - Class A | TH2Member
Holdings [Line Items]
Percent of Net Asset Value	1.50%
Fidelity Advisor Conservative Income Bond Fund - Class A | TH3Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class A | TH4Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class A | TH5Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class A | TH6Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class A | TH7Member
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class A | TH8Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Conservative Income Bond Fund - Class A | TH9Member
Holdings [Line Items]
Percent of Net Asset Value	1%
Fidelity Advisor Conservative Income Bond Fund - Class A | QDUSGovernmentandUSGovernmentAgencyObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	17%
Fidelity Advisor Conservative Income Bond Fund - Class A | QDAAAMember
Holdings [Line Items]
Percent of Net Asset Value	14.40%
Fidelity Advisor Conservative Income Bond Fund - Class A | QDAAMember
Holdings [Line Items]
Percent of Net Asset Value	3.50%
Fidelity Advisor Conservative Income Bond Fund - Class A | QDAMember
Holdings [Line Items]
Percent of Net Asset Value	24.80%
Fidelity Advisor Conservative Income Bond Fund - Class A | QDBBBMember
Holdings [Line Items]
Percent of Net Asset Value	17.20%
Fidelity Advisor Conservative Income Bond Fund - Class A | QDShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	23.10%
Fidelity Advisor Conservative Income Bond Fund - Class A | United States
Holdings [Line Items]
Percent of Net Asset Value	83.80%
Fidelity Advisor Conservative Income Bond Fund - Class A | United Kingdom
Holdings [Line Items]
Percent of Net Asset Value	3%
Fidelity Advisor Conservative Income Bond Fund - Class A | Canada
Holdings [Line Items]
Percent of Net Asset Value	3.40%
Fidelity Advisor Conservative Income Bond Fund - Class A | Netherlands
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class A | Germany
Holdings [Line Items]
Percent of Net Asset Value	3.50%
Fidelity Advisor Conservative Income Bond Fund - Class A | OtherMember
Holdings [Line Items]
Percent of Net Asset Value	1.10%
Fidelity Advisor Conservative Income Bond Fund - Class A | Japan
Holdings [Line Items]
Percent of Net Asset Value	1.20%
Fidelity Advisor Conservative Income Bond Fund - Class A | Ireland
Holdings [Line Items]
Percent of Net Asset Value	0.80%
Fidelity Advisor Conservative Income Bond Fund - Class A | France
Holdings [Line Items]
Percent of Net Asset Value	0.70%
Fidelity Advisor Conservative Income Bond Fund - Class A | Switzerland
Holdings [Line Items]
Percent of Net Asset Value	1.40%
Fidelity Advisor Conservative Income Bond Fund - Class A | AAUSTreasuryObligationsMember
Holdings [Line Items]
Percent of Net Asset Value	17%
Fidelity Advisor Conservative Income Bond Fund - Class A | AACorporateBondsMember
Holdings [Line Items]
Percent of Net Asset Value	45.30%
Fidelity Advisor Conservative Income Bond Fund - Class A | AAAssetBackedSecuritiesMember
Holdings [Line Items]
Percent of Net Asset Value	14.40%
Fidelity Advisor Conservative Income Bond Fund - Class A | AAOtherInvestmentsMember
Holdings [Line Items]
Percent of Net Asset Value	0.20%
Fidelity Advisor Conservative Income Bond Fund - Class A | AAShortTermInvestmentsandNetOtherAssetsLiabilitiesMember
Holdings [Line Items]
Percent of Net Asset Value	23.10%