| Shareholder Report | 12 Months Ended |
| Sep. 30, 2024 USD ($) Holding |
| Shareholder Report [Line Items] | |
| Document Type | N-CSR |
| Amendment Flag | false |
| Registrant Name | Federated Hermes Income Securities Trust |
| Entity Central Index Key | 0000789281 |
| Entity Investment Company Type | N-1A |
| Document Period End Date | Sep. 30, 2024 |
| C000024664 | |
| Shareholder Report [Line Items] | |
| Fund Name | Federated Hermes Inflation Protected Securities Fund |
| Class Name | Class A Shares |
| Trading Symbol | RRFAX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the Federated Hermes Inflation Protected Securities Fund (the "Fund") for the period of October 1, 2023 to September 30, 2024. |
| Shareholder Report Annual or Semi-Annual | Annual Shareholder Report |
| Additional Information [Text Block] | You can find additional information at FederatedHermes.com/us/FundInformation |
| Additional Information Phone Number | 1-800-341-7400 |
| Additional Information Website | <span style="text-decoration: underline solid rgb(0, 0, 0); box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left;">FederatedHermes.com/us/FundInformation</span></span>" id="sjs-B19"><span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left;"><span style="text-decoration: underline solid rgb(0, 0, 0); box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left;">FederatedHermes.com/us/FundInformation</span></span> |
| Expenses [Text Block] | What were the Fund costs for the last year? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class A Shares $62 0.59% |
| Expenses Paid, Amount | $ 62 |
| Expense Ratio, Percent | 0.59% |
| Factors Affecting Performance [Text Block] | Management's Discussion of Fund Performance The following discussion compares the performance of the Fund to the Bloomberg US Treasury Inflation Protected Securities (TIPS) Index (“Index”) to show how the Fund’s performance compares to the returns of similar investments for the reporting period. See the Average Annual Total Returns table below for the returns of the Fund and related indexes, including the Bloomberg US Aggregate Bond Index, which represents the overall U.S. fixed-income market. The Fund seeks to provide current income and real total returns by investing in inflation-indexed bonds, other fixed-income securities and derivatives. Top Contributors to Performance ■ Yield curve positioning added to relative Fund performance. The Fund was positioned for a steeper curve with shorter-maturity bonds outperforming longer-maturity bonds. Selling long-maturity Treasury futures and buying short-term Treasury futures were used for this steepening position. ■ Duration management contributed to relative Fund performance. The Fund was positioned longer in duration than the Index. Top Detractor from Performance ■ Sector/security selection detracted from relative Fund performance. The Fund was overweight longer-maturity Treasury Inflation-Protected Securities relative to the Index. This detracted from Fund performance along with the derivative positions used to hedge that stance. |
| Performance Past Does Not Indicate Future [Text] | Keep in mind that the Fund’s past performance is not a good predictor of how the Fund will perform in the future. |
| Line Graph [Table Text Block] | Class A Shares with sales load Bloomberg US Aggregate Bond Index Bloomberg US Treasury Inflation Protected Securities (TIPS) Index 9/30/2014 $9,546 $10,000 $10,000 9/30/2015 $9,220 $10,294 $9,917 9/30/2016 $9,649 $10,829 $10,570 9/30/2017 $9,724 $10,836 $10,493 9/30/2018 $9,869 $10,705 $10,536 9/30/2019 $10,463 $11,807 $11,286 9/30/2020 $11,448 $12,632 $12,424 9/30/2021 $11,978 $12,518 $13,069 9/30/2022 $10,602 $10,691 $11,557 9/30/2023 $10,624 $10,760 $11,701 9/30/2024 $11,591 $12,004 $12,847 |
| Average Annual Return [Table Text Block] | Average Annual Total Returns Fund/Index 1 Year 5 Years 10 Years Class A Shares with sales load 4.18% 1.13% 1.49% Class A Shares without sales load 9.10% 2.07% 1.96% Bloomberg US Aggregate Bond Index Footnote Reference 11.57% 0.33% 1.84% Bloomberg US Treasury Inflation Protected Securities (TIPS) Index 9.79% 2.62% 2.54% Footnote Description Footnote * The Fund has designated the Bloomberg US Aggregate Bond Index as its new broad-based securities market index in accordance with the SEC’s revised definition for such an index. Visit FederatedHermes.com/us/FundInformation |
| 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. |
| Performance Table Market Index Changed [Text Block] | The Fund has designated the Bloomberg US Aggregate Bond Index as its new broad-based securities market index in accordance with the SEC’s revised definition for such an index. |
| AssetsNet | $ 107,139,973 |
| Holdings Count | Holding | 34 |
| Advisory Fees Paid, Amount | $ 0 |
| InvestmentCompanyPortfolioTurnover | 87% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics Net Assets $107,139,973 Number of Investments 34 Portfolio Turnover 87% Total Advisory Fees Paid $0 |
| Holdings [Text Block] | Top Security Types (% of Net Assets) Value Value Cash Equivalents 3.8% Collaterized Mortgage Obligations 4.3% U.S Treasury Securities 91.7% |
| Material Fund Change [Text Block] | |
| C000024665 | |
| Shareholder Report [Line Items] | |
| Fund Name | Federated Hermes Inflation Protected Securities Fund |
| Class Name | Class C Shares |
| Trading Symbol | RRFCX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the Federated Hermes Inflation Protected Securities Fund (the "Fund") for the period of October 1, 2023 to September 30, 2024. |
| Shareholder Report Annual or Semi-Annual | Annual Shareholder Report |
| Additional Information [Text Block] | You can find additional information at FederatedHermes.com/us/FundInformation |
| Additional Information Phone Number | 1-800-341-7400 |
| Additional Information Website | <span style="text-decoration: underline solid rgb(0, 0, 0); box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left;">FederatedHermes.com/us/FundInformation</span></span>" id="sjs-B45"><span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left;"><span style="text-decoration: underline solid rgb(0, 0, 0); box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left;">FederatedHermes.com/us/FundInformation</span></span> |
| Expenses [Text Block] | What were the Fund costs for the last year? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class C Shares $138 1.33% |
| Expenses Paid, Amount | $ 138 |
| Expense Ratio, Percent | 1.33% |
| Factors Affecting Performance [Text Block] | Management's Discussion of Fund Performance The following discussion compares the performance of the Fund to the Bloomberg US Treasury Inflation Protected Securities (TIPS) Index (“Index”) to show how the Fund’s performance compares to the returns of similar investments for the reporting period. See the Average Annual Total Returns table below for the returns of the Fund and related indexes, including the Bloomberg US Aggregate Bond Index, which represents the overall U.S. fixed-income market. The Fund seeks to provide current income and real total returns by investing in inflation-indexed bonds, other fixed-income securities and derivatives. Top Contributors to Performance ■ Yield curve positioning added to relative Fund performance. The Fund was positioned for a steeper curve with shorter-maturity bonds outperforming longer-maturity bonds. Selling long-maturity Treasury futures and buying short-term Treasury futures were used for this steepening position. ■ Duration management contributed to relative Fund performance. The Fund was positioned longer in duration than the Index. Top Detractor from Performance ■ Sector/security selection detracted from relative Fund performance. The Fund was overweight longer-maturity Treasury Inflation-Protected Securities relative to the Index. This detracted from Fund performance along with the derivative positions used to hedge that stance. |
| Performance Past Does Not Indicate Future [Text] | Keep in mind that the Fund’s past performance is not a good predictor of how the Fund will perform in the future. |
| Line Graph [Table Text Block] | Class C Shares Bloomberg US Aggregate Bond Index Bloomberg US Treasury Inflation Protected Securities (TIPS) Index 9/30/2014 $10,000 $10,000 $10,000 9/30/2015 $9,579 $10,294 $9,917 9/30/2016 $9,952 $10,829 $10,570 9/30/2017 $9,958 $10,836 $10,493 9/30/2018 $10,035 $10,705 $10,536 9/30/2019 $10,558 $11,807 $11,286 9/30/2020 $11,466 $12,632 $12,424 9/30/2021 $11,905 $12,518 $13,069 9/30/2022 $10,457 $10,691 $11,557 9/30/2023 $10,478 $10,760 $11,701 9/30/2024 $11,432 $12,004 $12,847 |
| Average Annual Return [Table Text Block] | Average Annual Total Returns Fund/Index 1 Year 5 Years 10 Years Class C Shares with sales load 7.16% 1.29% 1.35% Class C Shares without sales load 8.16% 1.29% 1.35% Bloomberg US Aggregate Bond Index Footnote Reference 11.57% 0.33% 1.84% Bloomberg US Treasury Inflation Protected Securities (TIPS) Index 9.79% 2.62% 2.54% Footnote Description Footnote * The Fund has designated the Bloomberg US Aggregate Bond Index as its new broad-based securities market index in accordance with the SEC’s revised definition for such an index. Visit FederatedHermes.com/us/FundInformation |
| 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. |
| Performance Table Market Index Changed [Text Block] | The Fund has designated the Bloomberg US Aggregate Bond Index as its new broad-based securities market index in accordance with the SEC’s revised definition for such an index. |
| AssetsNet | $ 107,139,973 |
| Holdings Count | Holding | 34 |
| Advisory Fees Paid, Amount | $ 0 |
| InvestmentCompanyPortfolioTurnover | 87% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics Net Assets $107,139,973 Number of Investments 34 Portfolio Turnover 87% Total Advisory Fees Paid $0 |
| Holdings [Text Block] | Top Security Types (% of Net Assets) Value Value Cash Equivalents 3.8% Collaterized Mortgage Obligations 4.3% U.S Treasury Securities 91.7% |
| Material Fund Change [Text Block] | |
| C000024666 | |
| Shareholder Report [Line Items] | |
| Fund Name | Federated Hermes Inflation Protected Securities Fund |
| Class Name | Institutional Shares |
| Trading Symbol | RRFIX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the Federated Hermes Inflation Protected Securities Fund (the "Fund") for the period of October 1, 2023 to September 30, 2024. |
| Shareholder Report Annual or Semi-Annual | Annual Shareholder Report |
| Additional Information [Text Block] | You can find additional information at FederatedHermes.com/us/FundInformation |
| Additional Information Phone Number | 1-800-341-7400 |
| Additional Information Website | <span style="text-decoration: underline solid rgb(0, 0, 0); box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left;">FederatedHermes.com/us/FundInformation</span></span>" id="sjs-B71"><span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left;"><span style="text-decoration: underline solid rgb(0, 0, 0); box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left;">FederatedHermes.com/us/FundInformation</span></span> |
| Expenses [Text Block] | What were the Fund costs for the last year? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Institutional Shares $36 0.34% |
| Expenses Paid, Amount | $ 36 |
| Expense Ratio, Percent | 0.34% |
| Factors Affecting Performance [Text Block] | Management's Discussion of Fund Performance The following discussion compares the performance of the Fund to the Bloomberg US Treasury Inflation Protected Securities (TIPS) Index (“Index”) to show how the Fund’s performance compares to the returns of similar investments for the reporting period. See the Average Annual Total Returns table below for the returns of the Fund and related indexes, including the Bloomberg US Aggregate Bond Index, which represents the overall U.S. fixed-income market. The Fund seeks to provide current income and real total returns by investing in inflation-indexed bonds, other fixed-income securities and derivatives. Top Contributors to Performance ■ Yield curve positioning added to relative Fund performance. The Fund was positioned for a steeper curve with shorter-maturity bonds outperforming longer-maturity bonds. Selling long-maturity Treasury futures and buying short-term Treasury futures were used for this steepening position. ■ Duration management contributed to relative Fund performance. The Fund was positioned longer in duration than the Index. Top Detractor from Performance ■ Sector/security selection detracted from relative Fund performance. The Fund was overweight longer-maturity Treasury Inflation-Protected Securities relative to the Index. This detracted from Fund performance along with the derivative positions used to hedge that stance. |
| Performance Past Does Not Indicate Future [Text] | Keep in mind that the Fund’s past performance is not a good predictor of how the Fund will perform in the future. |
| Line Graph [Table Text Block] | Institutional Shares Bloomberg US Aggregate Bond Index Bloomberg US Treasury Inflation Protected Securities (TIPS) Index 9/30/2014 $10,000 $10,000 $10,000 9/30/2015 $9,681 $10,294 $9,917 9/30/2016 $10,152 $10,829 $10,570 9/30/2017 $10,257 $10,836 $10,493 9/30/2018 $10,444 $10,705 $10,536 9/30/2019 $11,101 $11,807 $11,286 9/30/2020 $12,182 $12,632 $12,424 9/30/2021 $12,774 $12,518 $13,069 9/30/2022 $11,333 $10,691 $11,557 9/30/2023 $11,388 $10,760 $11,701 9/30/2024 $12,449 $12,004 $12,847 |
| Average Annual Return [Table Text Block] | Average Annual Total Returns Fund/Index 1 Year 5 Years 10 Years Institutional Shares 9.31% 2.32% 2.21% Bloomberg US Aggregate Bond Index Footnote Reference 11.57% 0.33% 1.84% Bloomberg US Treasury Inflation Protected Securities (TIPS) Index 9.79% 2.62% 2.54% Footnote Description Footnote * The Fund has designated the Bloomberg US Aggregate Bond Index as its new broad-based securities market index in accordance with the SEC’s revised definition for such an index. Visit FederatedHermes.com/us/FundInformation |
| 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. |
| Performance Table Market Index Changed [Text Block] | The Fund has designated the Bloomberg US Aggregate Bond Index as its new broad-based securities market index in accordance with the SEC’s revised definition for such an index. |
| AssetsNet | $ 107,139,973 |
| Holdings Count | Holding | 34 |
| Advisory Fees Paid, Amount | $ 0 |
| InvestmentCompanyPortfolioTurnover | 87% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics Net Assets $107,139,973 Number of Investments 34 Portfolio Turnover 87% Total Advisory Fees Paid $0 |
| Holdings [Text Block] | Top Security Types (% of Net Assets) Value Value Cash Equivalents 3.8% Collaterized Mortgage Obligations 4.3% U.S Treasury Securities 91.7% |
| Material Fund Change [Text Block] | |
| C000233371 | |
| Shareholder Report [Line Items] | |
| Fund Name | Federated Hermes Inflation Protected Securities Fund |
| Class Name | Class R6 Shares |
| Trading Symbol | FIPRX |
| Annual or Semi-Annual Statement [Text Block] | This annual shareholder report contains important information about the Federated Hermes Inflation Protected Securities Fund (the "Fund") for the period of October 1, 2023 to September 30, 2024. |
| Shareholder Report Annual or Semi-Annual | Annual Shareholder Report |
| Additional Information [Text Block] | You can find additional information at FederatedHermes.com/us/FundInformation |
| Additional Information Phone Number | 1-800-341-7400 |
| Additional Information Website | <span style="text-decoration: underline solid rgb(0, 0, 0); box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left;">FederatedHermes.com/us/FundInformation</span></span>" id="sjs-B97"><span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left;"><span style="text-decoration: underline solid rgb(0, 0, 0); box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 12px; font-weight: 400; grid-area: auto; line-height: 18px; margin: 0px; overflow: visible; text-align: left;">FederatedHermes.com/us/FundInformation</span></span> |
| Expenses [Text Block] | What were the Fund costs for the last year? (based on a hypothetical $10,000 investment) Class Name Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Class R6 Shares $31 0.30% |
| Expenses Paid, Amount | $ 31 |
| Expense Ratio, Percent | 0.30% |
| Factors Affecting Performance [Text Block] | Management's Discussion of Fund Performance The following discussion compares the performance of the Fund to the Bloomberg US Treasury Inflation Protected Securities (TIPS) Index (“Index”) to show how the Fund’s performance compares to the returns of similar investments for the reporting period. See the Average Annual Total Returns table below for the returns of the Fund and related indexes, including the Bloomberg US Aggregate Bond Index, which represents the overall U.S. fixed-income market. The Fund seeks to provide current income and real total returns by investing in inflation-indexed bonds, other fixed-income securities and derivatives. Top Contributors to Performance ■ Yield curve positioning added to relative Fund performance. The Fund was positioned for a steeper curve with shorter-maturity bonds outperforming longer-maturity bonds. Selling long-maturity Treasury futures and buying short-term Treasury futures were used for this steepening position. ■ Duration management contributed to relative Fund performance. The Fund was positioned longer in duration than the Index. Top Detractor from Performance ■ Sector/security selection detracted from relative Fund performance. The Fund was overweight longer-maturity Treasury Inflation-Protected Securities relative to the Index. This detracted from Fund performance along with the derivative positions used to hedge that stance. |
| Performance Past Does Not Indicate Future [Text] | Keep in mind that the Fund’s past performance is not a good predictor of how the Fund will perform in the future. |
| Line Graph [Table Text Block] | Class R6 Shares Bloomberg US Aggregate Bond Index Bloomberg US Treasury Inflation Protected Securities (TIPS) Index 9/30/2014 $10,000 $10,000 $10,000 9/30/2015 $9,681 $10,294 $9,917 9/30/2016 $10,152 $10,829 $10,570 9/30/2017 $10,257 $10,836 $10,493 9/30/2018 $10,444 $10,705 $10,536 9/30/2019 $11,101 $11,807 $11,286 9/30/2020 $12,182 $12,632 $12,424 9/30/2021 $12,774 $12,518 $13,069 9/30/2022 $11,334 $10,691 $11,557 9/30/2023 $11,400 $10,760 $11,701 9/30/2024 $12,461 $12,004 $12,847 |
| Average Annual Return [Table Text Block] | Average Annual Total Returns Fund/Index 1 Year 5 Years 10 Years Class R6 Shares Footnote Reference 9.31% 2.34% 2.22% Bloomberg US Aggregate Bond Index Footnote Reference 11.57% 0.33% 1.84% Bloomberg US Treasury Inflation Protected Securities (TIPS) Index 9.79% 2.62% 2.54% Footnote Description Footnote a The Fund's Class R6 Shares commenced operations on December 29, 2021. For the periods prior to the commencement of operations of the Class R6 Shares, the performance information shown is for the Fund's Institutional Shares. The performance of the Institutional Shares has not been adjusted to reflect the expenses applicable to the Class R6 Shares since the Class R6 Shares have a lower expense ratio than the expense ratio of the Institutional Shares. Footnote * The Fund has designated the Bloomberg US Aggregate Bond Index as its new broad-based securities market index in accordance with the SEC’s revised definition for such an index. Visit FederatedHermes.com/us/FundInformation |
| 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. |
| Performance Table Market Index Changed [Text Block] | The Fund has designated the Bloomberg US Aggregate Bond Index as its new broad-based securities market index in accordance with the SEC’s revised definition for such an index. |
| AssetsNet | $ 107,139,973 |
| Holdings Count | Holding | 34 |
| Advisory Fees Paid, Amount | $ 0 |
| InvestmentCompanyPortfolioTurnover | 87% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics Net Assets $107,139,973 Number of Investments 34 Portfolio Turnover 87% Total Advisory Fees Paid $0 |
| Holdings [Text Block] | Top Security Types (% of Net Assets) Value Value Cash Equivalents 3.8% Collaterized Mortgage Obligations 4.3% U.S Treasury Securities 91.7% |
| Material Fund Change [Text Block] | |
