Label	Element	Value
Risk Return Abstract	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	EQ ADVISORS TRUST
Prospectus Date	rr_ProspectusDate	May 01, 2025
EQ Goldman Sachs Mid Cap Value 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/Goldman Sachs Mid Cap Value 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 IB and Class K Shares</span>
Objective [Heading]	rr_ObjectiveHeading	<span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective:</span>
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Seeks to achieve long-term capital appreciation.
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 64% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	64.00%
Other Expenses, New Fund, Based on Estimates [Text]	rr_OtherExpensesNewFundBasedOnEstimates	<span style="color:#000000;font-family:Arial;font-size:8pt;">Based on estimated amounts for the current fiscal year.</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 any borrowings for investment purposes, in equity securities of mid-cap companies (or other financial instruments that derive their value from the securities of such companies). For purposes of this Portfolio, as of December 31, 2024, mid-cap companies are those companies with public stock market capitalizations generally between $1 billion and $100 billion; however, this capitalization range will change over time with market conditions. The Portfolio invests in value opportunities, which the Sub-Adviser defines as companies with identifiable competitive advantages whose intrinsic values are not reflected in their stock prices. Although the Portfolio will invest primarily in publicly traded U.S. securities, including real estate investment trusts (“REITS”), it may invest up to 25% of its net assets in foreign securities, including securities of issuers in countries with emerging markets or economies and securities quoted in foreign currencies. The Sub-Adviser’s equity investment process involves: (1) using multiple industry-specific valuation metrics to identify real economic value and company potential in stocks, screened by valuation, profitability and business characteristics; (2) conducting in-depth company research and assessing overall business quality; and (3) buying those securities that a sector portfolio manager recommends, taking into account feedback from the rest of the portfolio management team. The Portfolio may invest in the aggregate up to 20% of its net assets in large- and small-cap companies and in fixed income securities, such as government, corporate and bank debt obligations. The Sub-Adviser may decide to sell a position for various reasons, including valuation and price considerations, readjustment of the Sub-Adviser’s outlook based on subsequent events, the Sub-Adviser’s ongoing assessment of the quality and effectiveness of management, if new investment ideas offer the potential for better risk/reward profiles than existing holdings, or for risk management purposes. In addition, the Sub-Adviser may sell a position in order to meet shareholder redemptions.
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-year, five-year and since inception periods through December 31, 2024, compared to the returns of a broad-based securities market index.The additional securities market 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.Class K shares have not commenced operations as of the date of this Prospectus.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-year, five-year and since inception periods 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 One Year or Less [Text]	rr_PerformanceOneYearOrLess	<span style="color:#000000;font-family:Arial;font-size:10pt;">Class K shares have not commenced operations as of the date of this Prospectus.</span>
Performance Additional Market Index [Text]	rr_PerformanceAdditionalMarketIndex	<span style="font-family:Arial;font-size:10pt;">The additional </span><span style="font-family:Arial;font-size:10pt;margin-left:0%;">securities market index shows how the Portfolio's performance compared with the returns of another index that has characteristics </span><span style="font-family:Arial;font-size:10pt;">relevant to the Portfolio's investment 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)20.71%2020 4th QuarterWorst quarter (% and time period)-29.62%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 Goldman Sachs Mid Cap Value 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 Goldman Sachs Mid Cap Value 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 Goldman Sachs Mid Cap Value 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 Goldman Sachs Mid Cap Value 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 Goldman Sachs Mid Cap Value Portfolio | Mid-Cap and Small-Cap Company Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Mid-Cap and Small-Cap Company Risk —  Mid-cap and small-cap companies carry additional risks because the operating histories of these companies tend to be more limited, their earnings and revenues less predictable (and some companies may be experiencing significant losses), and their share prices more volatile than those of larger, more established companies, all of which can negatively affect their value. In general, these risks are greater for small-cap companies than for mid-cap companies.
EQ Goldman Sachs Mid Cap Value Portfolio | Investment Style Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Investment Style Risk —  The Portfolio may use a particular style or set of styles — in this case, a “value” style — to select investments. A particular style may be out of favor or may not produce the best results over short or longer time periods. Value stocks are subject to the risks that, notwithstanding that a stock is selling at a discount to its perceived true worth, the stock’s full value may never be fully recognized or realized by the market, or its price may go down. In addition, there is the risk that a stock judged to be undervalued may actually have been appropriately priced at the time of investment.
EQ Goldman Sachs Mid Cap Value Portfolio | Real Estate Investing Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Real Estate Investing Risk —  Real estate-related investments may decline in value as a result of factors affecting the overall real estate industry. Real estate is a cyclical business, highly sensitive to supply and demand and general and local economic conditions and characterized by intense competition and periodic overbuilding. Real estate income and values also may be greatly affected by demographic trends, such as population shifts or changing tastes, preferences (such as remote work arrangements or online shopping) and values. Losses may occur from, for example, casualty or condemnation, or extended vacancies of properties, and government actions, such as tax law changes, zoning law changes, regulatory limitations on rents, or environmental regulations, also may have a major impact on real estate. The availability of mortgages and changes in interest rates may also affect real estate values. Changing interest rates and credit quality requirements also will affect the cash flow of real estate companies and their ability to meet capital needs or refinance their obligations. In addition, global climate change may have a significant adverse effect on property and security values and may exacerbate the risks of natural disasters. Real estate investment trusts (“REITs”) generally invest directly in real estate (equity REITs), in mortgages secured by interests in real estate (mortgage REITs) or in some combination of the two (hybrid REITs). Investing in REITs exposes investors to the risks of owning real estate directly, as well as to risks that relate specifically to the way in which REITs are organized and operated. Equity REITs may be affected by changes in the value of the underlying property owned by the REIT, while mortgage REITs may be affected by the quality of any credit extended. Equity and mortgage REITs are also subject to heavy cash flow dependency, defaults by mortgagors and other borrowers, and self-liquidations. Operating REITs requires specialized management skills, and a portfolio that invests in REITs indirectly bears REIT management and administration expenses along with the direct expenses of the portfolio. Individual REITs may own a limited number of properties and may concentrate in a particular region or property type. Domestic REITs also must satisfy specific Internal Revenue Code requirements to qualify for the tax-free pass-through of net investment income and net realized gains distributed to shareholders. Failure to meet these requirements may have adverse consequences on the Portfolio. In addition, even the larger REITs in the industry tend to be small- to medium-sized companies in relation to the equity markets as a whole. Moreover, shares of REITs may trade less frequently and, therefore, are subject to more erratic price movements than securities of larger issuers.
EQ Goldman Sachs Mid Cap Value 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 Goldman Sachs Mid Cap Value Portfolio | Credit Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Credit Risk —  The Portfolio is subject to the risk that the issuer or guarantor of a fixed income security, or the counterparty to a transaction, is unable or unwilling, or is perceived as unable or unwilling, to make timely interest or principal payments or otherwise honor its obligations, or defaults completely, which may cause the Portfolio’s holdings to lose value. The downgrade of a security’s credit rating may decrease its value. Lower credit quality also may lead to greater volatility in the price of a security and may negatively affect a security’s liquidity. The credit quality of a security can deteriorate suddenly and rapidly. The Portfolio may experience a significant or complete loss on a fixed income security or a transaction.
EQ Goldman Sachs Mid Cap Value 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 Goldman Sachs Mid Cap Value 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 Goldman Sachs Mid Cap Value Portfolio | Emerging Markets Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Emerging Markets Risk —  The risks associated with investments in emerging market countries often are significant and vary from jurisdiction to jurisdiction and company to company. Investments in emerging market countries are more susceptible to loss than investments in more developed foreign countries and may present market, credit, currency, liquidity, legal, political, technical and other risks different from, or greater than, the risks of investing in more developed foreign countries. Emerging market countries may be more likely to experience rapid and significant adverse developments in their political or economic structures, intervene in financial markets, restrict foreign investments, impose high withholding or other taxes on foreign investments, impose restrictive exchange control regulations, or nationalize or expropriate the assets of private companies, which may have negative impacts on transaction costs, market price, investment returns, and the legal rights and remedies available to the Portfolio. In addition, the securities markets of emerging market countries generally are smaller, less liquid and more volatile than those of more developed foreign countries, and emerging market countries often have less uniformity in regulatory, accounting, auditing and financial reporting requirements or standards, which may impact the availability and quality of information about issuers, and less reliable clearance and settlement, registration and custodial procedures. Emerging market countries also may be subject to high inflation and rapid currency devaluations, and currency-hedging techniques may be unavailable in certain emerging market countries. In addition, some emerging market countries may be heavily dependent on international trade, which can materially affect their securities markets. Securities of issuers traded on foreign exchanges may be suspended. The likelihood of such suspensions may be higher for securities of issuers in emerging market countries than in countries with more developed markets.
EQ Goldman Sachs Mid Cap Value 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 Goldman Sachs Mid Cap Value 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. In addition, the risks associated with investing in a narrowly defined geographic area are generally more pronounced with respect to investments in emerging market countries.
EQ Goldman Sachs Mid Cap Value Portfolio | Interest Rate Risk [Member]
Risk Return Abstract	rr_RiskReturnAbstract
Risk [Text Block]	rr_RiskTextBlock	Interest Rate Risk —  Changes in interest rates may affect the yield, liquidity and value of investments in debt securities or other income-producing securities. Changes in interest rates also may affect the value of other securities. When interest rates rise, the value of the Portfolio’s debt securities generally declines. Conversely, when interest rates decline, the value of the Portfolio’s debt securities generally rises. Typically, the longer the maturity (i.e., the term of a debt security) or duration (i.e., a measure of the sensitivity of a debt security to changes in market interest rates, based on the entire cash flow associated with the security) of a debt security, the greater the effect a change in interest rates could have on the security’s price. Thus, the sensitivity of the Portfolio’s debt securities to interest rate risk will increase the greater the duration of those securities. Changes in government or central bank monetary policy may have a substantial and immediate impact on interest rates, which could result in losses to the Portfolio.
EQ Goldman Sachs Mid Cap Value 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 Goldman Sachs Mid Cap Value Portfolio | Class IB
Risk Return Abstract	rr_RiskReturnAbstract
Shareholder Fees (fees paid directly from your investment)	rr_ShareholderFeeOther
Management Fee	rr_ManagementFeesOverAssets	0.77%
Distribution and/or Service Fees (12b-1 fees)	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other Expenses	rr_OtherExpensesOverAssets	0.17%
Total Annual Portfolio Operating Expenses	rr_ExpensesOverAssets	1.19%
Fee Waiver and/or Expense Reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.10%)	[1]
Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement	rr_NetExpensesOverAssets	1.09%
1 Year	rr_ExpenseExampleYear01	$ 111
3 Years	rr_ExpenseExampleYear03	368
5 Years	rr_ExpenseExampleYear05	645
10 Years	rr_ExpenseExampleYear10	$ 1,434
2019	rr_AnnualReturn2019	30.78%
2020	rr_AnnualReturn2020	8.46%
2021	rr_AnnualReturn2021	30.49%
2022	rr_AnnualReturn2022	(10.60%)
2023	rr_AnnualReturn2023	11.22%
2024	rr_AnnualReturn2024	11.89%
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, 2020
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	20.71%
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	(29.62%)
OneYear	rr_AverageAnnualReturnYear01	11.89%
FiveYears	rr_AverageAnnualReturnYear05	9.50%
SinceInception	rr_AverageAnnualReturnSinceInception	10.62%
InceptionDate	rr_AverageAnnualReturnInceptionDate	Oct. 22, 2018
EQ Goldman Sachs Mid Cap Value Portfolio | Class K
Risk Return Abstract	rr_RiskReturnAbstract
Shareholder Fees (fees paid directly from your investment)	rr_ShareholderFeeOther
Management Fee	rr_ManagementFeesOverAssets	0.77%
Distribution and/or Service Fees (12b-1 fees)	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.17%	[2]
Total Annual Portfolio Operating Expenses	rr_ExpensesOverAssets	0.94%
Fee Waiver and/or Expense Reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.10%)	[1]
Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement	rr_NetExpensesOverAssets	0.84%
1 Year	rr_ExpenseExampleYear01	$ 86
3 Years	rr_ExpenseExampleYear03	290
5 Years	rr_ExpenseExampleYear05	510
10 Years	rr_ExpenseExampleYear10	$ 1,146
EQ Goldman Sachs Mid Cap Value Portfolio | Russell 1000® Index (reflects no deduction for fees, expenses, or taxes)
Risk Return Abstract	rr_RiskReturnAbstract
OneYear	rr_AverageAnnualReturnYear01	24.51%
FiveYears	rr_AverageAnnualReturnYear05	14.28%
SinceInception	rr_AverageAnnualReturnSinceInception	14.62%
EQ Goldman Sachs Mid Cap Value Portfolio | Russell Midcap® Value Index (reflects no deduction for fees, expenses, or taxes)
Risk Return Abstract	rr_RiskReturnAbstract
OneYear	rr_AverageAnnualReturnYear01	13.07%
FiveYears	rr_AverageAnnualReturnYear05	8.59%
SinceInception	rr_AverageAnnualReturnSinceInception	9.12%

[1] 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 1.09% for Class IB shares and 0.84% 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.

[2] Based on estimated amounts for the current fiscal year.