Form N-CSR Cover
| Form N-CSR Cover | 6 Months Ended |
| Jun. 30, 2024 | |
| Shareholder Report [Line Items] | |
| Document Type | N-CSRS |
| Amendment Flag | false |
| Registrant Name | T. ROWE PRICE FIXED INCOME SERIES, INC. |
| Entity Central Index Key | 0000920467 |
| Entity Investment Company Type | N-1A |
| Document Period End Date | Jun. 30, 2024 |
Shareholder Report
| Shareholder Report | 6 Months Ended |
| Jun. 30, 2024 USD ($) Holding | |
| Shareholder Report [Line Items] | |
| Document Type | N-CSRS |
| Amendment Flag | false |
| Registrant Name | T. ROWE PRICE FIXED INCOME SERIES, INC. |
| Entity Central Index Key | 0000920467 |
| Entity Investment Company Type | N-1A |
| Document Period End Date | Jun. 30, 2024 |
| C000005520 | |
| Shareholder Report [Line Items] | |
| Fund Name | Limited-Term Bond Portfolio |
| Class Name | Limited-Term Bond Portfolio Class |
| Trading Symbol | QAAGWX |
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about Limited-Term Bond Portfolio (the "fund") for the period of January 1, 2024 to June 30, 2024. You can find the fund’s prospectus, financial information on Form N‑CSR (which includes required tax information for dividends), holdings, proxy voting information, and other information at www.troweprice.com/prospectus info troweprice.com |
| Shareholder Report Annual or Semi-Annual | Semi-Annual Shareholder Report |
| Additional Information [Text Block] | You can find the fund’s prospectus, financial information on Form N‑CSR (which includes required tax information for dividends), holdings, proxy voting information, and other information at www.troweprice.com/prospectus info troweprice.com |
| Material Fund Change Notice [Text Block] | |
| Additional Information Phone Number | 1‑800‑638‑5660 |
| Additional Information Email | info@troweprice.com</span>" id="sjs-B20"><span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 13.3333px; font-weight: 400; grid-area: auto; line-height: 17.3333px; margin: 0px; overflow: visible; text-align: justify;">info@troweprice.com</span> |
| Additional Information Website | www.troweprice.com/prospectus</span>" id="sjs-B21"><span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 13.3333px; font-weight: 700; grid-area: auto; line-height: 17.3333px; margin: 0px; overflow: visible; text-align: justify;">www.troweprice.com/prospectus</span> |
| Expenses [Text Block] | What were the fund costs for the last six months? Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Limited-Term Bond Portfolio Class $25 0.50% |
| Expenses Paid, Amount | $ 25 |
| Expense Ratio, Percent | 0.50% |
| Updated Performance Information Location [Text Block] | If you invest directly with T. Rowe Price, you can elect to receive future shareholder reports or other important documents through electronic delivery by enrolling at www.troweprice.com/paperless |
| AssetsNet | $ 191,907,000 |
| Holdings Count | Holding | 802 |
| InvestmentCompanyPortfolioTurnover | 57.70% |
| Additional Fund Statistics [Text Block] | What are some fund statistics? Fund Statistics Total Net Assets (000s) $191,907 Number of Portfolio Holdings 802 |
| Additional Fund Statistics Significance or Limits [Text Block] | Portfolio Turnover Rate 57.7% |
| Holdings [Text Block] | Credit Quality Allocation* AAA Rated 15.9 % AA Rated 10.2 A Rated 20.8 BBB Rated 23.5 BB Rated and Below 0.4 Not Rated 1.6 U.S. Treasury Securities 21.0 U.S. Government Agency Securities 5.5 Reserves 1.1 *Credit ratings for the securities held in the Fund are provided by Moody’s, Standard & Poor’s, and Fitch and are converted to the Standard & Poor’s nomenclature. A rating of AAA represents the highest-rated securities, and a rating of D represents the lowest rated securities. If the ratings agencies differ, the highest rating is applied to the security. If a rating is not available, the security is classified as Not Rated. The rating of the underlying investment vehicle is used to determine the creditworthiness of credit default swaps and sovereign securities. The Fund is not rated by any agency. |
| Largest Holdings [Text Block] | Top Ten Holdings U.S. Treasury Notes 20.0 % Federal National Mortgage Assn. 3.3 Federal Home Loan Mortgage 1.1 Government National Mortgage Assn. 1.1 U.S. Treasury Inflation-Indexed Notes 1.0 AbbVie 0.7 HPEFS Equipment Trust 0.7 AmeriCredit Automobile Receivables Trust 0.7 CarMax Auto Owner Trust 0.7 Verus Securitization Trust 0.7 |
| Material Fund Change [Text Block] | |
| Updated Prospectus Web Address | www.troweprice.com/paperless</span>" id="sjs-B34"><span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 10.6667px; font-weight: 400; grid-area: auto; line-height: 13.8667px; margin: 0px; overflow: visible; text-align: justify;">www.troweprice.com/paperless</span> |
| C000005521 | |
| Shareholder Report [Line Items] | |
| Fund Name | Limited-Term Bond Portfolio |
| Class Name | Limited-Term Bond Portfolio-II Class |
| Trading Symbol | QAAGUX |
| Annual or Semi-Annual Statement [Text Block] | This semi-annual shareholder report contains important information about Limited-Term Bond Portfolio (the "fund") for the period of January 1, 2024 to June 30, 2024. You can find the fund’s prospectus, financial information on Form N‑CSR (which includes required tax information for dividends), holdings, proxy voting information, and other information at www.troweprice.com/prospectus info troweprice.com |
| Shareholder Report Annual or Semi-Annual | Semi-Annual Shareholder Report |
| Additional Information [Text Block] | You can find the fund’s prospectus, financial information on Form N‑CSR (which includes required tax information for dividends), holdings, proxy voting information, and other information at www.troweprice.com/prospectus info troweprice.com |
| Material Fund Change Notice [Text Block] | |
| Additional Information Phone Number | 1‑800‑638‑5660 |
| Additional Information Email | info@troweprice.com</span>" id="sjs-B45"><span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 13.3333px; font-weight: 400; grid-area: auto; line-height: 17.3333px; margin: 0px; overflow: visible; text-align: justify;">info@troweprice.com</span> |
| Additional Information Website | www.troweprice.com/prospectus</span>" id="sjs-B46"><span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 13.3333px; font-weight: 700; grid-area: auto; line-height: 17.3333px; margin: 0px; overflow: visible; text-align: justify;">www.troweprice.com/prospectus</span> |
| Expenses [Text Block] | What were the fund costs for the last six months? Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Limited-Term Bond Portfolio-II Class $38 0.75% |
| Expenses Paid, Amount | $ 38 |
| Expense Ratio, Percent | 0.75% |
| Updated Performance Information Location [Text Block] | If you invest directly with T. Rowe Price, you can elect to receive future shareholder reports or other important documents through electronic delivery by enrolling at www.troweprice.com/paperless |
| AssetsNet | $ 191,907,000 |
| Holdings Count | Holding | 802 |
| InvestmentCompanyPortfolioTurnover | 57.70% |
| Additional Fund Statistics [Text Block] | What are some fund statistics? Fund Statistics Total Net Assets (000s) $191,907 Number of Portfolio Holdings 802 |
| Additional Fund Statistics Significance or Limits [Text Block] | Portfolio Turnover Rate 57.7% |
| Holdings [Text Block] | Credit Quality Allocation* AAA Rated 15.9 % AA Rated 10.2 A Rated 20.8 BBB Rated 23.5 BB Rated and Below 0.4 Not Rated 1.6 U.S. Treasury Securities 21.0 U.S. Government Agency Securities 5.5 Reserves 1.1 *Credit ratings for the securities held in the Fund are provided by Moody’s, Standard & Poor’s, and Fitch and are converted to the Standard & Poor’s nomenclature. A rating of AAA represents the highest-rated securities, and a rating of D represents the lowest rated securities. If the ratings agencies differ, the highest rating is applied to the security. If a rating is not available, the security is classified as Not Rated. The rating of the underlying investment vehicle is used to determine the creditworthiness of credit default swaps and sovereign securities. The Fund is not rated by any agency. |
| Largest Holdings [Text Block] | Top Ten Holdings U.S. Treasury Notes 20.0 % Federal National Mortgage Assn. 3.3 Federal Home Loan Mortgage 1.1 Government National Mortgage Assn. 1.1 U.S. Treasury Inflation-Indexed Notes 1.0 AbbVie 0.7 HPEFS Equipment Trust 0.7 AmeriCredit Automobile Receivables Trust 0.7 CarMax Auto Owner Trust 0.7 Verus Securitization Trust 0.7 |
| Material Fund Change [Text Block] | |
| Updated Prospectus Web Address | www.troweprice.com/paperless</span>" id="sjs-B59"><span style="box-sizing: border-box; color: rgb(0, 0, 0); display: inline; flex-wrap: nowrap; font-size: 10.6667px; font-weight: 400; grid-area: auto; line-height: 13.8667px; margin: 0px; overflow: visible; text-align: justify;">www.troweprice.com/paperless</span> |
Shareholder Report, Holdings (D
| Shareholder Report, Holdings (Details) | Jun. 30, 2024 |
| C000005520 | U.S. Treasury Notes | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 20% |
| C000005520 | Federal National Mortgage Assn. | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.30% |
| C000005520 | Federal Home Loan Mortgage | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.10% |
| C000005520 | Government National Mortgage Assn. | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.10% |
| C000005520 | U.S. Treasury Inflation-Indexed Notes | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1% |
| C000005520 | AbbVie | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| C000005520 | HPEFS Equipment Trust | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| C000005520 | AmeriCredit Automobile Receivables Trust | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| C000005520 | CarMax Auto Owner Trust | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| C000005520 | Verus Securitization Trust | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| C000005520 | AAA Rated | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 15.90% |
| C000005520 | AA Rated | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.20% |
| C000005520 | A Rated | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 20.80% |
| C000005520 | BBB Rated | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 23.50% |
| C000005520 | BB Rated and Below | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| C000005520 | Not Rated | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.60% |
| C000005520 | U.S. Treasury Securities | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 21% |
| C000005520 | U.S. Government Agency Securities | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.50% |
| C000005521 | U.S. Treasury Notes | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 20% |
| C000005521 | Federal National Mortgage Assn. | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 3.30% |
| C000005521 | Federal Home Loan Mortgage | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.10% |
| C000005521 | Government National Mortgage Assn. | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.10% |
| C000005521 | U.S. Treasury Inflation-Indexed Notes | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1% |
| C000005521 | AbbVie | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| C000005521 | HPEFS Equipment Trust | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| C000005521 | AmeriCredit Automobile Receivables Trust | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| C000005521 | CarMax Auto Owner Trust | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| C000005521 | Verus Securitization Trust | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.70% |
| C000005521 | AAA Rated | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 15.90% |
| C000005521 | AA Rated | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 10.20% |
| C000005521 | A Rated | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 20.80% |
| C000005521 | BBB Rated | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 23.50% |
| C000005521 | BB Rated and Below | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 0.40% |
| C000005521 | Not Rated | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 1.60% |
| C000005521 | U.S. Treasury Securities | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 21% |
| C000005521 | U.S. Government Agency Securities | |
| Holdings [Line Items] | |
| Percent of Net Asset Value | 5.50% |