Shareholder Report | 12 Months Ended | 58 Months Ended | 112 Months Ended |
Dec. 31, 2024 USD ($) Holding | Dec. 31, 2024 USD ($) Holding | Dec. 31, 2024 USD ($) Holding |
Shareholder Report [Line Items] | | | |
Document Type | N-CSR | | |
Amendment Flag | false | | |
Registrant Name | T. ROWE PRICE INDEX TRUST, INC. | | |
Entity Central Index Key | 0000858581 | | |
Entity Investment Company Type | N-1A | | |
Document Period End Date | Dec. 31, 2024 | | |
C000005457 | | | |
Shareholder Report [Line Items] | | | |
Fund Name | Equity Index 500 Fund | | |
Class Name | Investor Class | | |
Trading Symbol | PREIX | | |
Shareholder Report Annual or Semi-Annual | 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-B19"><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 | | |
Expenses [Text Block] | What were the fund costs for the last year? Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Equity Index 500 Fund - Investor Class $21 0.18% | | |
Expenses Paid, Amount | $ 21 | | |
Expense Ratio, Percent | 0.18% | | |
Factors Affecting Performance [Text Block] | What drove fund performance during the past 12 months? U.S. stocks produced strong gains for the second consecutive year in 2024, and various equity indexes reached all-time highs during the year. In the final months of the period, equity investors generally welcomed not only looser monetary policy but also the U.S. election results. Former President Donald Trump defeated Vice President Kamala Harris in the presidential election, and Republican victories in the House of Representatives and Senate races gave them majorities in both chambers of Congress. Information technology names produced robust results during the period as the sector benefited from strong investor interest in companies expected to benefit from artificial intelligence developments. Semiconductors and semiconductor equipment and hardware companies performed very well during the year, as NVIDIA and Apple were two of the top-performing companies in the portfolio. No sectors detracted from absolute returns during the reporting period. The trajectories of the economy, corporate earnings, and interest rates are unpredictable, and investor sentiment toward the broad market and various market segments could change without warning. Our main task is not to determine which stocks or sectors may perform best but, rather, to replicate the structure of the S&P 500 Index and closely track its performance. | | |
Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a good predictor of the fund’s future performance. | | |
Average Annual Return [Table Text Block] | Average Annual Total Returns 1 Year 5 Years 10 Years Equity Index 500 Fund (Investor Class) 24.78 % 14.32 % 12.87 % S&P 500 Index (Regulatory/Strategy Benchmark) 25.02 14.53 13.10 The preceding line graph shows the value of a hypothetical $10,000 investment in the fund over the past 10 fiscal year periods or since inception (for funds lacking 10-year records). The fund’s performance information included in the line graph and table above is compared with a regulatory required index that represents an overall securities market (Regulatory Benchmark). In addition, the line graph and table may also include one or more indexes that more closely aligns to the fund's investment strategy (Strategy Benchmark(s)). Due to new SEC Rules on shareholder reporting the fund adopted a new broad-based securities market index, referred to as the Regulatory Benchmark. Market index returns do not include expenses, which are deducted from fund returns. The fund's total return figures reflect the reinvestment of dividends and capital gains, if any.Neither the fund’s returns nor the index returns reflect the deduction of taxes that a shareholder would pay on fund distributions or redemptions of fund shares. The fund’s past performance is not a good predictor of the fund’s future performance. | | |
No Deduction of Taxes [Text Block] | Neither the fund’s returns nor the index returns reflect the deduction of taxes that a shareholder would pay on fund distributions or redemptions of fund shares. | | |
Performance Table Market Index Changed [Text Block] | Due to new SEC Rules on shareholder reporting the fund adopted a new broad-based securities market index, referred to as the Regulatory Benchmark. | | |
Updated Performance Information Location [Text Block] | Updated performance information can be found at www.troweprice.com. | | |
Distribution of Capital [Text Block] | The fund's total return figures reflect the reinvestment of dividends and capital gains, if any. | | |
AssetsNet | $ 34,057,034,000 | $ 34,057,034,000 | $ 34,057,034,000 |
Holdings Count | Holding | 506 | 506 | 506 |
Advisory Fees Paid, Amount | $ 5,627,000 | | |
InvestmentCompanyPortfolioTurnover | 3.60% | | |
Additional Fund Statistics [Text Block] | What are some fund statistics? Fund Statistics Total Net Assets (000s) $34,057,034 Number of Portfolio Holdings 506 | | |
Holdings [Text Block] | Sector Information Technology 32.2 % Financials 13.6 Consumer Discretionary 11.2 Health Care 10.1 Communication Services 9.4 Industrials & Business Services 8.2 Consumer Staples 5.6 Energy 3.1 Utilities 2.3 Other 4.3 | | |
Largest Holdings [Text Block] | Top Ten Holdings Apple 7.6 % NVIDIA 6.6 Microsoft 6.3 Amazon.com 4.1 Alphabet 4.0 Meta Platforms 2.6 Tesla 2.3 Broadcom 2.2 Berkshire Hathaway 1.7 JPMorgan Chase 1.4 | | |
Updated Prospectus Web Address | www.troweprice.com/paperless | | |
C000159677 | | | |
Shareholder Report [Line Items] | | | |
Fund Name | Equity Index 500 Fund | | |
Class Name | I Class | | |
Trading Symbol | PRUIX | | |
Shareholder Report Annual or Semi-Annual | 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-B48"><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 | | |
Expenses [Text Block] | What were the fund costs for the last year? Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Equity Index 500 Fund - I Class $6 0.05% | | |
Expenses Paid, Amount | $ 6 | | |
Expense Ratio, Percent | 0.05% | | |
Factors Affecting Performance [Text Block] | What drove fund performance during the past 12 months? U.S. stocks produced strong gains for the second consecutive year in 2024, and various equity indexes reached all-time highs during the year. In the final months of the period, equity investors generally welcomed not only looser monetary policy but also the U.S. election results. Former President Donald Trump defeated Vice President Kamala Harris in the presidential election, and Republican victories in the House of Representatives and Senate races gave them majorities in both chambers of Congress. Information technology names produced robust results during the period as the sector benefited from strong investor interest in companies expected to benefit from artificial intelligence developments. Semiconductors and semiconductor equipment and hardware companies performed very well during the year, as NVIDIA and Apple were two of the top-performing companies in the portfolio. No sectors detracted from absolute returns during the reporting period. The trajectories of the economy, corporate earnings, and interest rates are unpredictable, and investor sentiment toward the broad market and various market segments could change without warning. Our main task is not to determine which stocks or sectors may perform best but, rather, to replicate the structure of the S&P 500 Index and closely track its performance. | | |
Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a good predictor of the fund’s future performance. | | |
Average Annual Return [Table Text Block] | Average Annual Total Returns 1 Year 5 Years Since Inception 8/28/15 Equity Index 500 Fund (I Class) 24.95 % 14.47 % 14.27 % S&P 500 Index (Regulatory/Strategy Benchmark) 25.02 14.53 14.34 The preceding line graph shows the value of a hypothetical $500,000 investment in the fund over the past 10 fiscal year periods or since inception (for funds lacking 10-year records). The fund’s performance information included in the line graph and table above is compared with a regulatory required index that represents an overall securities market (Regulatory Benchmark). In addition, the line graph and table may also include one or more indexes that more closely aligns to the fund's investment strategy (Strategy Benchmark(s)). Due to new SEC Rules on shareholder reporting the fund adopted a new broad-based securities market index, referred to as the Regulatory Benchmark. Market index returns do not include expenses, which are deducted from fund returns. The fund's total return figures reflect the reinvestment of dividends and capital gains, if any.Neither the fund’s returns nor the index returns reflect the deduction of taxes that a shareholder would pay on fund distributions or redemptions of fund shares. The fund’s past performance is not a good predictor of the fund’s future performance. | | |
Performance Inception Date | | | Aug. 28, 2015 |
No Deduction of Taxes [Text Block] | Neither the fund’s returns nor the index returns reflect the deduction of taxes that a shareholder would pay on fund distributions or redemptions of fund shares. | | |
Performance Table Market Index Changed [Text Block] | Due to new SEC Rules on shareholder reporting the fund adopted a new broad-based securities market index, referred to as the Regulatory Benchmark. | | |
Updated Performance Information Location [Text Block] | Updated performance information can be found at www.troweprice.com. | | |
Distribution of Capital [Text Block] | The fund's total return figures reflect the reinvestment of dividends and capital gains, if any. | | |
AssetsNet | $ 34,057,034,000 | $ 34,057,034,000 | $ 34,057,034,000 |
Holdings Count | Holding | 506 | 506 | 506 |
Advisory Fees Paid, Amount | $ 5,627,000 | | |
InvestmentCompanyPortfolioTurnover | 3.60% | | |
Additional Fund Statistics [Text Block] | What are some fund statistics? Fund Statistics Total Net Assets (000s) $34,057,034 Number of Portfolio Holdings 506 | | |
Holdings [Text Block] | Sector Information Technology 32.2 % Financials 13.6 Consumer Discretionary 11.2 Health Care 10.1 Communication Services 9.4 Industrials & Business Services 8.2 Consumer Staples 5.6 Energy 3.1 Utilities 2.3 Other 4.3 | | |
Largest Holdings [Text Block] | Top Ten Holdings Apple 7.6 % NVIDIA 6.6 Microsoft 6.3 Amazon.com 4.1 Alphabet 4.0 Meta Platforms 2.6 Tesla 2.3 Broadcom 2.2 Berkshire Hathaway 1.7 JPMorgan Chase 1.4 | | |
Updated Prospectus Web Address | www.troweprice.com/paperless | | |
C000219327 | | | |
Shareholder Report [Line Items] | | | |
Fund Name | Equity Index 500 Fund | | |
Class Name | Z Class | | |
Trading Symbol | TRHZX | | |
Shareholder Report Annual or Semi-Annual | 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-B78"><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 | | |
Expenses [Text Block] | What were the fund costs for the last year? Costs of a $10,000 investment Costs paid as a percentage of a $10,000 investment Equity Index 500 Fund - Z Class $0 0.00% | | |
Expenses Paid, Amount | $ 0 | | |
Expense Ratio, Percent | 0% | | |
Factors Affecting Performance [Text Block] | What drove fund performance during the past 12 months? U.S. stocks produced strong gains for the second consecutive year in 2024, and various equity indexes reached all-time highs during the year. In the final months of the period, equity investors generally welcomed not only looser monetary policy but also the U.S. election results. Former President Donald Trump defeated Vice President Kamala Harris in the presidential election, and Republican victories in the House of Representatives and Senate races gave them majorities in both chambers of Congress. Information technology names produced robust results during the period as the sector benefited from strong investor interest in companies expected to benefit from artificial intelligence developments. Semiconductors and semiconductor equipment and hardware companies performed very well during the year, as NVIDIA and Apple were two of the top-performing companies in the portfolio. No sectors detracted from absolute returns during the reporting period. The trajectories of the economy, corporate earnings, and interest rates are unpredictable, and investor sentiment toward the broad market and various market segments could change without warning. Our main task is not to determine which stocks or sectors may perform best but, rather, to replicate the structure of the S&P 500 Index and closely track its performance. | | |
Performance Past Does Not Indicate Future [Text] | The fund’s past performance is not a good predictor of the fund’s future performance. | | |
Average Annual Return [Table Text Block] | Average Annual Total Returns 1 Year Since Inception 3/16/20 Equity Index 500 Fund (Z Class) 25.01 % 22.60 % S&P 500 Index (Regulatory/Strategy Benchmark) 25.02 22.60 The preceding line graph shows the value of a hypothetical $10,000 investment in the fund over the past 10 fiscal year periods or since inception (for funds lacking 10-year records). The fund’s performance information included in the line graph and table above is compared with a regulatory required index that represents an overall securities market (Regulatory Benchmark). In addition, the line graph and table may also include one or more indexes that more closely aligns to the fund's investment strategy (Strategy Benchmark(s)). Due to new SEC Rules on shareholder reporting the fund adopted a new broad-based securities market index, referred to as the Regulatory Benchmark. Market index returns do not include expenses, which are deducted from fund returns. The fund's total return figures reflect the reinvestment of dividends and capital gains, if any.Neither the fund’s returns nor the index returns reflect the deduction of taxes that a shareholder would pay on fund distributions or redemptions of fund shares. The fund’s past performance is not a good predictor of the fund’s future performance. | | |
Performance Inception Date | | Mar. 16, 2020 | |
No Deduction of Taxes [Text Block] | Neither the fund’s returns nor the index returns reflect the deduction of taxes that a shareholder would pay on fund distributions or redemptions of fund shares. | | |
Performance Table Market Index Changed [Text Block] | Due to new SEC Rules on shareholder reporting the fund adopted a new broad-based securities market index, referred to as the Regulatory Benchmark. | | |
Updated Performance Information Location [Text Block] | Updated performance information can be found at www.troweprice.com. | | |
Distribution of Capital [Text Block] | The fund's total return figures reflect the reinvestment of dividends and capital gains, if any. | | |
AssetsNet | $ 34,057,034,000 | $ 34,057,034,000 | $ 34,057,034,000 |
Holdings Count | Holding | 506 | 506 | 506 |
Advisory Fees Paid, Amount | $ 5,627,000 | | |
InvestmentCompanyPortfolioTurnover | 3.60% | | |
Additional Fund Statistics [Text Block] | What are some fund statistics? Fund Statistics Total Net Assets (000s) $34,057,034 Number of Portfolio Holdings 506 | | |
Holdings [Text Block] | Sector Information Technology 32.2 % Financials 13.6 Consumer Discretionary 11.2 Health Care 10.1 Communication Services 9.4 Industrials & Business Services 8.2 Consumer Staples 5.6 Energy 3.1 Utilities 2.3 Other 4.3 | | |
Largest Holdings [Text Block] | Top Ten Holdings Apple 7.6 % NVIDIA 6.6 Microsoft 6.3 Amazon.com 4.1 Alphabet 4.0 Meta Platforms 2.6 Tesla 2.3 Broadcom 2.2 Berkshire Hathaway 1.7 JPMorgan Chase 1.4 | | |
Updated Prospectus Web Address | www.troweprice.com/paperless | | |