Label	Element	Value
Risk Return Abstract	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	EQ ADVISORS TRUST
Prospectus Date	rr_ProspectusDate	May 01, 2025
EQ International Equity Index Portfolio
Risk Return Abstract	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	<span style="color:#000000;font-family:Arial;font-size:11pt;font-weight:bold;">EQ/International Equity Index Portfolio</span><span style="color:#000000;font-family:Arial;font-size:11pt;font-weight:bold;line-height:13pt;">  </span><span style="color:#000000;font-family:Arial;font-size:11pt;font-weight:bold;">— Class IA, Class IB and Class K Shares</span>
Objective [Heading]	rr_ObjectiveHeading	<span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;margin-left:0%;">Investment Objective:</span>
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Seeks to achieve a total return (before expenses) that approximates the total return performance of a composite index comprised of 40% DJ Euro-STOXX 50 Index, 25% FTSE 100 Index, 25% TOPIX Index, and 10% S&P/ASX 200 Index, including reinvestment of dividends, at a risk level consistent with that of the composite index.
Expense [Heading]	rr_ExpenseHeading	<span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;text-transform:uppercase;">Fees and Expenses of the Portfolio</span>
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	The following table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Portfolio. The table below does not reflect any fees and expenses associated with variable life insurance contracts and variable annuity certificates and contracts (“Contracts”), which would increase overall fees and expenses. See the Contract prospectus for a description of those fees and expenses.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	<span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Shareholder Fees</span> <br/><span style="color:#000000;font-family:Arial;font-size:10pt;">(fees paid directly from your investment)</span>
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	<span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Annual Portfolio Operating Expenses</span><span style="color:#000000;font-family:Arial;font-size:10pt;">(expenses that you pay each year as a percentage of the value of your investment)</span>
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	<span style="font-family:Arial;font-size:8pt;">April 30, 2026</span>
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	<span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;text-transform:uppercase;">Portfolio Turnover</span>
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Portfolio pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 5% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	5.00%
Expenses Restated to Reflect Current [Text]	rr_ExpensesRestatedToReflectCurrent	<span style="color:#000000;font-family:Arial;font-size:8pt;">Fee Waiver and/or Expense Reimbursement information has been restated to reflect the current Expense Limitation Arrangement.</span>
Expense Example [Heading]	rr_ExpenseExampleHeading	<span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Example</span>
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Portfolio with the cost of investing in other portfolios. The Example assumes that you invest $10,000 in the Portfolio for the periods indicated, that your investment has a 5% return each year, that the Portfolio’s operating expenses remain the same, and that the Expense Limitation Arrangement is not renewed. This Example does not reflect any Contract-related fees and expenses including redemption fees (if any) at the Contract level. If such fees and expenses were reflected, the total expenses would be higher. Although your actual costs may be higher or lower, based on these assumptions, whether you redeem or hold your shares, your costs would be:
Strategy [Heading]	rr_StrategyHeading	<span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;text-transform:uppercase;">Investments, Risks, and Performance</span><span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Investment Strategy</span>
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Under normal circumstances the Portfolio invests at least 80% of its net assets, plus borrowings for investment purposes, in equity securities of companies represented in the FTSE 100 Index (“FTSE 100”), TOPIX Index (“TOPIX”), DJ EuroSTOXX 50 Index (“EuroSTOXX 50”), and S&P/ASX 200 Index (“S&P/ASX 200”). The Portfolio will allocate its assets approximately 25% to securities in the FTSE 100, 25% to securities in the TOPIX, 40% to securities in the EuroSTOXX 50, and 10% to securities in the S&P/ASX 200. Actual allocations may vary by up to 3%. The FTSE 100 represents the performance of the 100 largest UK-domiciled blue chip companies. The TOPIX comprises all companies listed on the First Section of the Tokyo Stock Exchange (approximately 1,694 companies). The EuroSTOXX 50 index represents the performance of the 50 largest companies in 11 Eurozone countries. The S&P/ASX 200 represents the 200 largest and most liquid publicly listed companies in Australia. Each of these indices is weighted by market capitalization. The Portfolio uses a strategy that is commonly referred to as an indexing strategy. With respect to investments in companies represented in the FTSE 100, EuroSTOXX 50, and S&P/ASX 200, the Sub-Adviser generally uses a replication technique, although a sampling approach may be used in certain circumstances. With respect to investments in companies represented in the TOPIX, the Sub-Adviser selects investments using a stratified sampling construction process in which the Sub-Adviser selects a sub-set of the companies represented in the index based on the Sub-Adviser’s analysis of key risk factors and other characteristics. Such factors include industry weightings, market capitalizations, return variability, and yields.
Risk [Heading]	rr_RiskHeading	<span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Principal Risks</span>
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	<span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Risk/Return Bar Chart and Table</span>
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio’s performance from year to year and by showing how the Portfolio’s average annual total returns for the past one, five and ten years through December 31, 2024, compared to the returns of a broad-based securities market index.The additional index shows how the Portfolio’s performance compared with the returns of another index that has characteristics relevant to the Portfolio’s investment strategies.Past performance is not an indication of future performance.The performance results do not reflect any Contract-related fees and expenses, which would reduce the performance results.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	<span style="font-family:Arial;font-size:10pt;margin-left:0%;">The bar chart and table below provide some indication of the risks of investing in the Portfolio by showing changes in the Portfolio’s performance from year to year and by showing how the Portfolio’s average annual total returns for the past one, five and ten years through December 31, </span><span style="font-family:Arial;font-size:10pt;">2024, compared to the returns of a broad-based securities market index.</span>
Performance Additional Market Index [Text]	rr_PerformanceAdditionalMarketIndex	<span style="font-family:Arial;font-size:10pt;">The additional index shows how </span><span style="font-family:Arial;font-size:10pt;margin-left:0%;">the Portfolio’s performance compared with the returns of another index that has characteristics relevant to the Portfolio’s investment </span><span style="font-family:Arial;font-size:10pt;">strategies.</span>
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	<span style="font-family:Arial;font-size:10pt;">Past performance is not an indication of future performance.</span>
Bar Chart [Heading]	rr_BarChartHeading	<span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Calendar Year Annual Total Returns — Class IB</span>
Bar Chart Does Not Reflect Sales Loads [Text]	rr_BarChartDoesNotReflectSalesLoads	<span style="color:#000000;font-family:Arial;font-size:10pt;">The performance results do not reflect any Contract-related fees and expenses, which would reduce the performance results.</span>
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best quarter (% and time period)19.90%2022 4th QuarterWorst quarter (% and time period)-25.26%2020 1st Quarter
Performance Table Heading	rr_PerformanceTableHeading	<span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Average Annual Total Returns</span>
EQ International Equity Index Portfolio | Risk Lose Money [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	The value of your investment may fall, sometimes sharply, and you could lose money by investing in the Portfolio.
EQ International Equity Index Portfolio | Risk Not Insured Depository Institution [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
EQ International Equity Index Portfolio | Market Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Market Risk —  The Portfolio is subject to the risk that the securities markets will move down, sometimes rapidly and unpredictably, based on overall economic conditions and other factors, which may negatively affect Portfolio performance. Securities markets also may experience long periods of decline in value. The value of a security can be more volatile than the market as a whole and can perform differently from the market as a whole. Any issuer of securities may perform poorly, causing the value of its securities to decline. Poor performance may be caused by a variety of factors, such as poor management decisions; reduced demand for the issuer’s goods or services; competitive pressures; negative perception in the marketplace; loss of major customers; strategic initiatives such as mergers or acquisitions and the market response to any such initiatives; and the historical and prospective earnings of the issuer. The value of a security also may decline due to general market conditions, such as real or perceived adverse economic or political conditions, inflation rates and/or investor expectations concerning such rates, changes in interest rates, recessions, or adverse investor sentiment generally. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Even when securities markets perform well, there can be no assurance that the investments held by the Portfolio will increase in value along with the broader market. Changes in the financial condition of (or other event affecting) a single issuer can impact an individual sector or industry, or the securities markets as a whole. The value of a security also may decline due to factors that affect a particular sector or industry, such as tariffs, labor shortages, or increased production costs and competitive conditions within the sector or industry. Geopolitical events, including acts of terrorism, tensions, war or other open conflicts between nations, or political or economic dysfunction within nations that are global economic powers or major oil or other commodities producers, may lead to overall instability in world economies and markets generally and have led, and may in the future lead, to increased market volatility and may have adverse long-term effects. World markets, or those in a particular region, may all react in similar fashion to economic, political or other developments. Events such as environmental and natural disasters or other catastrophes, public health crises (such as epidemics and pandemics), social unrest, and cybersecurity incidents, and governments’ reactions (or failure to react) to such events, could cause uncertainty in the markets and may adversely affect the performance of the global economy. Impacts from climate change may include significant risks to global financial assets and economic growth. The extent and duration of such events and resulting market disruptions could be substantial and could magnify the impact of other risks to the Portfolio. The value and liquidity of the Portfolio’s investments may be negatively affected by developments in other countries and regions, whether or not the Portfolio invests in securities of issuers located in or with significant exposure to the countries or regions directly affected. Changes in government or central bank policies, changes in existing laws and regulations, and political, diplomatic and other events within the United States and abroad could cause uncertainty in the markets, may affect investor and consumer confidence, and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. High public debt and deficits in the United States and other countries create ongoing systemic and market risks and policymaking uncertainty and may negatively affect economic conditions and the values of markets, sectors and companies in which the Portfolio invests. In addition, markets and market participants are increasingly reliant on information data systems. Inaccurate data, software or other technology malfunctions, programming inaccuracies, unauthorized use or access, and similar circumstances may impair the performance of these systems and may have an adverse impact upon a single issuer, a group of issuers, or the market at large. Furthermore, impacts from the rapidly growing use of artificial intelligence technologies, including by market participants, may include significant risks to global financial markets.
EQ International Equity Index Portfolio | Equity Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Equity Risk —  In general, the values of stocks and other equity securities fluctuate, and sometimes widely fluctuate, in response to changes in a company’s financial condition as well as general market, economic and political conditions and other factors. Stock markets tend to run in cycles, with periods when stock prices generally go up and periods when stock prices generally go down. However, stock markets also can move up and down rapidly and unpredictably. In addition, common stock prices may be particularly sensitive to rising interest rates, which increase borrowing costs and the costs of capital. The Portfolio may experience a significant or complete loss on its investment in an equity security.
EQ International Equity Index Portfolio | Foreign Securities Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Foreign Securities Risk —  Investments in foreign securities involve risks in addition to those associated with investments in U.S. securities. Foreign markets may be less liquid, more volatile and subject to less government supervision and regulation than U.S. markets, and it may take more time to clear and settle trades involving foreign securities, which could negatively impact the Portfolio’s investments and cause it to lose money. Security values also may be negatively affected by changes in the exchange rates between the U.S. dollar and foreign currencies. Differences between U.S. and foreign legal, political and economic systems, regulatory regimes and market practices, as well as changes in international trading patterns, trade barriers and other protectionist trade policies (including those of the United States), tariffs, governmental instability, acts of terrorism, war or other open conflicts, or other political, diplomatic or economic actions, also may adversely impact security values. Foreign securities are also subject to the risks associated with the potential imposition of economic or other sanctions against a particular foreign country, its nationals, businesses or industries. World markets, or those in a particular region, may all react in similar fashion to economic, political or other developments. Events and evolving conditions in certain economies or markets may alter the risks associated with investments tied to countries or regions that historically were perceived as comparatively stable and make such investments riskier and more volatile. Regardless of where a company is organized or its stock is traded, its performance may be significantly affected by events in regions from which it derives its profits or in which it conducts significant operations.
EQ International Equity Index Portfolio | Currency Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Currency Risk —  Investments that are denominated in or that provide exposure to foreign currencies are subject to the risk that those currencies will decline in value relative to the U.S. dollar. Any such decline may erode or reverse any potential gains from an investment in securities denominated in foreign currency or may widen existing loss. In the case of hedging positions, there is the risk that the U.S. dollar will decline in value relative to the currency being hedged. Currency rates may fluctuate significantly over short periods of time.
EQ International Equity Index Portfolio | European Economic Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	European Economic Risk —  The economies of European Union (“EU”) member countries and their trading partners, as well as the broader global economy, may be adversely affected by changes in the euro’s exchange rate, changes in EU or governmental regulations on trade, geopolitical and other events, including acts of terrorism, tensions, war or other open conflicts, and the threat of default or an actual default by an EU member country on its sovereign debt, which could negatively impact the Portfolio’s investments and cause it to lose money. Events in Europe may continue to impact the economies of every European country and their economic partners. The ongoing Russia-Ukraine conflict, the resulting responses by the United States and other countries, and the potential for wider conflict have had, and could continue to have, severe adverse effects on regional and global economies and could further increase volatility and uncertainty in the financial markets. In addition, uncertainties regarding the viability of the EU have impacted and may continue to impact regional and global markets. There are ongoing concerns regarding the economies of certain European countries and/or their sovereign debt following the United Kingdom’s withdrawal from the EU, commonly referred to as “Brexit”. Any further withdrawals from the EU could cause significant regional and global market disruption, which may negatively impact the Portfolio’s investments and cause it to lose money. Furthermore, the national politics of European countries have been unpredictable; unanticipated or sudden political or social developments may result in sudden and significant investment losses.
EQ International Equity Index Portfolio | Geographic Focus Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Geographic Focus Risk —  To the extent the Portfolio invests a significant portion of its assets in securities of companies domiciled, or exercising the predominant part of their economic activity, in one country or geographic region, it assumes the risk that economic, political, social and environmental conditions in that particular country or region will have a significant impact on the Portfolio’s investment performance and that the Portfolio’s performance will be more volatile than the performance of more geographically diversified funds.
EQ International Equity Index Portfolio | Japan Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Japan Risk —  Japan's economy may be subject to considerable degrees of economic, political and social instability, which could have a negative impact on Japanese securities. In recent years, Japan’s economic growth rate has generally remained low relative to other major developed economies, and it may remain low in the future. The Japanese economy is heavily dependent on international trade and has been, and may continue to be, adversely affected by, among other factors, trade tariffs, other protectionist measures and changes in government regulations on trade; competition from emerging economies; and downturns in the economies of its trading partners, including the United States. Currency fluctuations also may adversely impact the Japanese economy, including its export market. The Japanese economic growth rate also could be impacted by Bank of Japan monetary policies, low domestic consumption, rising interest rates and global inflation, tax increases, large government deficits, and volatility in the Japanese yen. Other factors, such as the occurrence of natural disasters and economic, political or social instability in or confrontations with neighboring countries, also could significantly disrupt economic activity and negatively impact the Japanese economy and Japanese issuers of securities. Any of these factors could have a material adverse impact on the holdings and performance of the Portfolio.
EQ International Equity Index Portfolio | Large-Cap Company Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Large-Cap Company Risk —  Larger more established companies may be unable to respond quickly to new competitive challenges such as changes in technology and consumer tastes, which may lead to a decline in their market price. Many larger companies also may not be able to attain the high growth rate of successful smaller companies, especially during extended periods of economic expansion.
EQ International Equity Index Portfolio | Index Strategy Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Index Strategy Risk —  The Portfolio employs an index strategy and generally will not modify its index strategy to respond to changes in market trends or the economy, which means that the Portfolio may be particularly susceptible to a general decline in the market segment relating to the relevant index. In addition, although the index strategy attempts to closely track the relevant index, the Portfolio may not invest in all of the securities in the index. Therefore, there can be no assurance that the performance of the index strategy will match that of the relevant index. To the extent that the Portfolio utilizes a representative sampling approach, it may experience greater tracking error than it would if the Portfolio sought to replicate the index.
EQ International Equity Index Portfolio | Portfolio Management Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Portfolio Management Risk —  The Portfolio is subject to the risk that strategies used by an investment manager and its securities selections fail to produce the intended results. An investment manager’s judgments or decisions about the quality, relative yield or value of, or market trends affecting, a particular security or issuer, industry, sector, region or market segment, or about the economy or interest rates, may be incorrect or otherwise may not produce the intended results, which may result in losses to the Portfolio. In addition, many processes used in Portfolio management, including security selection, rely, in whole or in part, on the use of various technologies. The Portfolio may suffer losses if there are imperfections, errors or limitations in the quantitative, analytic or other tools, resources, information and data used, or the analyses employed or relied on, by an investment manager, or if such tools, resources, information or data are used incorrectly, fail to produce the desired results, or otherwise do not work as intended. There can be no assurance that the use of these technologies will result in effective investment decisions for the Portfolio. In addition, the Portfolio could experience losses if an investment manager’s judgments about the risks associated with the Portfolio’s investment program prove to be incorrect.
EQ International Equity Index Portfolio | Sector Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Sector Risk —  From time to time, based on market or economic conditions, the Portfolio may have significant positions in one or more sectors of the market. To the extent the Portfolio invests more heavily in particular sectors, its performance will be especially sensitive to developments that significantly affect those sectors. Individual sectors may be more volatile, and may perform differently, than the broader market. The industries that constitute a sector may all react in the same way to economic, political, regulatory or other events.
EQ International Equity Index Portfolio | Class IA
Risk Return Abstract	rr_RiskReturnAbstract
Shareholder Fees (fees paid directly from your investment)	rr_ShareholderFeeOther
Management Fee	rr_ManagementFeesOverAssets	0.40%
Distribution and/or Service Fees (12b-1 fees)	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other Expenses	rr_OtherExpensesOverAssets	0.14%
Total Annual Portfolio Operating Expenses	rr_ExpensesOverAssets	0.79%
Fee Waiver and/or Expense Reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.07%)	[1],[2]
Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement	rr_NetExpensesOverAssets	0.72%
1 Year	rr_ExpenseExampleYear01	$ 74
3 Years	rr_ExpenseExampleYear03	245
5 Years	rr_ExpenseExampleYear05	432
10 Years	rr_ExpenseExampleYear10	$ 971
OneYear	rr_AverageAnnualReturnYear01	4.82%
FiveYears	rr_AverageAnnualReturnYear05	4.85%
TenYears	rr_AverageAnnualReturnYear10	4.93%
EQ International Equity Index Portfolio | Class IB
Risk Return Abstract	rr_RiskReturnAbstract
Shareholder Fees (fees paid directly from your investment)	rr_ShareholderFeeOther
Management Fee	rr_ManagementFeesOverAssets	0.40%
Distribution and/or Service Fees (12b-1 fees)	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other Expenses	rr_OtherExpensesOverAssets	0.14%
Total Annual Portfolio Operating Expenses	rr_ExpensesOverAssets	0.79%
Fee Waiver and/or Expense Reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.07%)	[1],[2]
Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement	rr_NetExpensesOverAssets	0.72%
1 Year	rr_ExpenseExampleYear01	$ 74
3 Years	rr_ExpenseExampleYear03	245
5 Years	rr_ExpenseExampleYear05	432
10 Years	rr_ExpenseExampleYear10	$ 971
2015	rr_AnnualReturn2015	(2.12%)
2016	rr_AnnualReturn2016	2.15%
2017	rr_AnnualReturn2017	23.29%
2018	rr_AnnualReturn2018	(15.25%)
2019	rr_AnnualReturn2019	22.19%
2020	rr_AnnualReturn2020	3.89%
2021	rr_AnnualReturn2021	10.91%
2022	rr_AnnualReturn2022	(11.92%)
2023	rr_AnnualReturn2023	19.04%
2024	rr_AnnualReturn2024	4.92%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	<span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Best quarter (% and time period)</span>
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Dec. 31, 2022
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	19.90%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	<span style="color:#000000;font-family:Arial;font-size:8pt;margin-left:0.0pt;">Worst quarter (% and time period)</span>
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Mar. 31, 2020
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(25.26%)
OneYear	rr_AverageAnnualReturnYear01	4.92%
FiveYears	rr_AverageAnnualReturnYear05	4.86%
TenYears	rr_AverageAnnualReturnYear10	4.93%
EQ International Equity Index Portfolio | Class K
Risk Return Abstract	rr_RiskReturnAbstract
Shareholder Fees (fees paid directly from your investment)	rr_ShareholderFeeOther
Management Fee	rr_ManagementFeesOverAssets	0.40%
Distribution and/or Service Fees (12b-1 fees)	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.14%
Total Annual Portfolio Operating Expenses	rr_ExpensesOverAssets	0.54%
Fee Waiver and/or Expense Reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.07%)	[1],[2]
Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement	rr_NetExpensesOverAssets	0.47%
1 Year	rr_ExpenseExampleYear01	$ 48
3 Years	rr_ExpenseExampleYear03	166
5 Years	rr_ExpenseExampleYear05	295
10 Years	rr_ExpenseExampleYear10	$ 670
OneYear	rr_AverageAnnualReturnYear01	5.17%
FiveYears	rr_AverageAnnualReturnYear05	5.11%
TenYears	rr_AverageAnnualReturnYear10	5.19%
EQ International Equity Index Portfolio | MSCI EAFE® Index (reflects no deduction for fees, expenses, or taxes)
Risk Return Abstract	rr_RiskReturnAbstract
OneYear	rr_AverageAnnualReturnYear01	3.82%
FiveYears	rr_AverageAnnualReturnYear05	4.73%
TenYears	rr_AverageAnnualReturnYear10	5.20%
EQ International Equity Index Portfolio | International Proxy Index (reflects no deduction for fees, expenses, or taxes)
Risk Return Abstract	rr_RiskReturnAbstract
OneYear	rr_AverageAnnualReturnYear01	5.92%	[3]
FiveYears	rr_AverageAnnualReturnYear05	5.61%	[3]
TenYears	rr_AverageAnnualReturnYear10	5.60%	[3]

[1] Fee Waiver and/or Expense Reimbursement information has been restated to reflect the current Expense Limitation Arrangement.

[2] Pursuant to a contract, Equitable Investment Management Group, LLC (the “Adviser”) has agreed to waive its and its affiliates’ management, administrative and other fees and, if necessary, make payments to the Portfolio to limit the expenses of the Portfolio through April 30, 2026 (unless the Board of Trustees consents to an earlier revision or termination of this arrangement) (“Expense Limitation Arrangement”) so that the annual operating expenses (including Acquired Fund Fees and Expenses) of the Portfolio (exclusive of taxes, interest, brokerage commissions, dividend and interest expenses on securities sold short, capitalized expenses, and extraordinary expenses not incurred in the ordinary course of the Portfolio’s business) do not exceed an annual rate of average daily net assets of 0.72% for Class IA and Class IB shares and 0.47% for Class K shares of the Portfolio. The Expense Limitation Arrangement may be terminated by the Adviser at any time after April 30, 2026. The Adviser may be reimbursed the amount of any such waivers or payments in the future provided that the waivers or payments are reimbursed within three years of the waivers or payments being recorded and the Portfolio’s expense ratio, after the reimbursement is taken into account, does not exceed the Portfolio’s expense cap at the time of the waiver or the Portfolio’s expense cap at the time of the reimbursement, whichever is lower.

[3] The composite index is a hypothetical combination of unmanaged indexes composed of the DJ EuroSTOXX 50® Index, FTSE 100 Index, TOPIX Index and S&P/ASX 200 Index at weightings of 40%, 25%, 25% and 10%, respectively.