| Shareholder Report | 6 Months Ended |
| Sep. 30, 2024 USD ($) Holding |
| Shareholder Report [Line Items] | |
| Document Type | N-CSRS |
| 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 |
| C000100297 | |
| Shareholder Report [Line Items] | |
| Fund Name | Federated Hermes Floating Rate Strategic Income Fund |
| Class Name | Class A Shares |
| Trading Symbol | FRSAX |
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about the Federated Hermes Floating Rate Strategic Income Fund (the "Fund") for the period of April 1, 2024 to September 30, 2024. |
| Shareholder Report Annual or Semi-Annual | Semi-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 six months? (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 $46 0.91% |
| Expenses Paid, Amount | $ 46 |
| Expense Ratio, Percent | 0.91% |
| AssetsNet | $ 410,252,000 |
| Holdings Count | Holding | 65 |
| InvestmentCompanyPortfolioTurnover | 4% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics Net Assets $410,252,000 Number of Investments 65 Portfolio Turnover 4% |
| Holdings [Text Block] | Top Security Types (% of Net Assets) Value Value Adjustable Rate Mortgages 0.1% Asset-Backed Securities 2.6% Corporate Bonds 5.3% Cash Equivalents 5.4% Exchange-Traded Funds 5.7% Trade Finance Agreements 9.0% Collateralized Mortgage Obligations 9.8% Floating Rate Loans 60.4% |
| Material Fund Change [Text Block] | |
| C000093604 | |
| Shareholder Report [Line Items] | |
| Fund Name | Federated Hermes Floating Rate Strategic Income Fund |
| Class Name | Institutional Shares |
| Trading Symbol | FFRSX |
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about the Federated Hermes Floating Rate Strategic Income Fund (the "Fund") for the period of April 1, 2024 to September 30, 2024. |
| Shareholder Report Annual or Semi-Annual | Semi-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-B38"><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 six months? (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 $34 0.66% |
| Expenses Paid, Amount | $ 34 |
| Expense Ratio, Percent | 0.66% |
| AssetsNet | $ 410,252,000 |
| Holdings Count | Holding | 65 |
| InvestmentCompanyPortfolioTurnover | 4% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics Net Assets $410,252,000 Number of Investments 65 Portfolio Turnover 4% |
| Holdings [Text Block] | Top Security Types (% of Net Assets) Value Value Adjustable Rate Mortgages 0.1% Asset-Backed Securities 2.6% Corporate Bonds 5.3% Cash Equivalents 5.4% Exchange-Traded Funds 5.7% Trade Finance Agreements 9.0% Collateralized Mortgage Obligations 9.8% Floating Rate Loans 60.4% |
| Material Fund Change [Text Block] | |
| C000176299 | |
| Shareholder Report [Line Items] | |
| Fund Name | Federated Hermes Floating Rate Strategic Income Fund |
| Class Name | Class R6 Shares |
| Trading Symbol | FFRLX |
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about the Federated Hermes Floating Rate Strategic Income Fund (the "Fund") for the period of April 1, 2024 to September 30, 2024. |
| Shareholder Report Annual or Semi-Annual | Semi-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-B57"><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 six months? (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 $33 0.65% |
| Expenses Paid, Amount | $ 33 |
| Expense Ratio, Percent | 0.65% |
| AssetsNet | $ 410,252,000 |
| Holdings Count | Holding | 65 |
| InvestmentCompanyPortfolioTurnover | 4% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics Net Assets $410,252,000 Number of Investments 65 Portfolio Turnover 4% |
| Holdings [Text Block] | Top Security Types (% of Net Assets) Value Value Adjustable Rate Mortgages 0.1% Asset-Backed Securities 2.6% Corporate Bonds 5.3% Cash Equivalents 5.4% Exchange-Traded Funds 5.7% Trade Finance Agreements 9.0% Collateralized Mortgage Obligations 9.8% Floating Rate Loans 60.4% |
| Material Fund Change [Text Block] | |
| C000024652 | |
| Shareholder Report [Line Items] | |
| Fund Name | Federated Hermes Fund for U.S. Government Securities |
| Class Name | Class A Shares |
| Trading Symbol | FUSGX |
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about the Federated Hermes Fund for U.S. Government Securities (the "Fund") for the period of April 1, 2024 to September 30, 2024. |
| Shareholder Report Annual or Semi-Annual | Semi-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-B76"><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 six months? (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 $49 0.96% |
| Expenses Paid, Amount | $ 49 |
| Expense Ratio, Percent | 0.96% |
| AssetsNet | $ 103,218,513 |
| Holdings Count | Holding | 146 |
| InvestmentCompanyPortfolioTurnover | 25% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics Net Assets $103,218,513 Number of Investments 146 Portfolio Turnover 25% Portfolio Turnover (excluding purchases and sales from dollar-roll transactions) 7% |
| Holdings [Text Block] | Top Security Types (% of Net Assets) Value Value Non-Agency Mortgage-Backed Securities 0.9% Collateralized Mortgage Obligations 2.9% Cash Equivalents 3.0% Asset-Backed Securities 3.0% U.S Government Agency Mortgage-Backed Securities 90.7% |
| Material Fund Change [Text Block] | |
| C000024654 | |
| Shareholder Report [Line Items] | |
| Fund Name | Federated Hermes Fund for U.S. Government Securities |
| Class Name | Class C Shares |
| Trading Symbol | FUSCX |
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about the Federated Hermes Fund for U.S. Government Securities (the "Fund") for the period of April 1, 2024 to September 30, 2024. |
| Shareholder Report Annual or Semi-Annual | Semi-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-B95"><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 six months? (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 $88 1.71% |
| Expenses Paid, Amount | $ 88 |
| Expense Ratio, Percent | 1.71% |
| AssetsNet | $ 103,218,513 |
| Holdings Count | Holding | 146 |
| InvestmentCompanyPortfolioTurnover | 25% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics Net Assets $103,218,513 Number of Investments 146 Portfolio Turnover 25% Portfolio Turnover (excluding purchases and sales from dollar-roll transactions) 7% |
| Holdings [Text Block] | Top Security Types (% of Net Assets) Value Value Non-Agency Mortgage-Backed Securities 0.9% Collateralized Mortgage Obligations 2.9% Cash Equivalents 3.0% Asset-Backed Securities 3.0% U.S Government Agency Mortgage-Backed Securities 90.7% |
| Material Fund Change [Text Block] | |
| C000219628 | |
| Shareholder Report [Line Items] | |
| Fund Name | Federated Hermes Fund for U.S. Government Securities |
| Class Name | Institutional Shares |
| Trading Symbol | FCBRX |
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about the Federated Hermes Fund for U.S. Government Securities (the "Fund") for the period of April 1, 2024 to September 30, 2024. |
| Shareholder Report Annual or Semi-Annual | Semi-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-B114"><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 six months? (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 $37 0.71% |
| Expenses Paid, Amount | $ 37 |
| Expense Ratio, Percent | 0.71% |
| AssetsNet | $ 103,218,513 |
| Holdings Count | Holding | 146 |
| InvestmentCompanyPortfolioTurnover | 25% |
| Additional Fund Statistics [Text Block] | Key Fund Statistics Net Assets $103,218,513 Number of Investments 146 Portfolio Turnover 25% Portfolio Turnover (excluding purchases and sales from dollar-roll transactions) 7% |
| Holdings [Text Block] | Top Security Types (% of Net Assets) Value Value Non-Agency Mortgage-Backed Securities 0.9% Collateralized Mortgage Obligations 2.9% Cash Equivalents 3.0% Asset-Backed Securities 3.0% U.S Government Agency Mortgage-Backed Securities 90.7% |
| Material Fund Change [Text Block] | |
