Objective, Primary [Text Block]

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Risk/Return [Heading]

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EQ/Quality Bond PLUS Portfolio – Class IA, IB and K Shares

Objective [Heading]

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Investment Objective:

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Seeks to achieve high current income consistent with moderate risk to capital.

Expense [Heading]

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FEES AND EXPENSES OF THE PORTFOLIO

Expense Narrative [Text Block]

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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]

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Shareholder Fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

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Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of thevalue of your investment)

Portfolio Turnover [Heading]

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PORTFOLIO TURNOVER

Portfolio Turnover [Text Block]

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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 173% of the average value of the Portfolio.

Portfolio Turnover, Rate

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173.00%

Expense Example [Heading]

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Example

Expense Example Narrative [Text Block]

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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, and that the Portfolio’s operating expenses remain the same. 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]

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INVESTMENTS, RISKS, AND PERFORMANCE Principal Investment Strategy:

Strategy Narrative [Text Block]

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Under normal circumstances, the Portfolio invests at least 80% of its net assets, plus borrowings for investment purposes, in debt securities. For this Portfolio, debt securities include direct and indirect investments in debt securities and investments in other investment companies and financial instruments that derive their value from such securities. The Portfolio invests primarily (either directly or indirectly through other investments) in securities, including government, corporate and agency

mortgage-

and asset-backed securities, that are rated investment grade at the time of purchase (

i.e.,

at least Baa by Moody’s Investors Service, Inc. (“Moody’s) or BBB by Standard & Poor’s Global Ratings (“S&P”) or Fitch Ratings Ltd. (“Fitch”)), or if unrated, fixed income securities that the Adviser or Sub-Adviser determines to be of comparable quality. Split rated securities, which are securities that receive different ratings from two or more rating agencies, will be considered to have the higher credit rating. The Portfolio also seeks to maintain an average aggregate quality rating of its portfolio securities of at least A (Moody’s or S&P or Fitch). In the event that the credit rating of a security held by the Portfolio falls below investment grade (or, in the case of unrated securities, the Sub-Adviser determines that the quality of such security has deteriorated below investment grade), the Portfolio will not be obligated to dispose of such security and may continue to hold the obligation if the Sub-Adviser believes such an investment is appropriate under the circumstances. The Portfolio may also purchase or sell futures contracts on fixed-income securities in lieu of investment directly in fixed-income securities themselves, and may utilize other types of derivatives, including swaps. The Portfolio may engage in active and frequent trading of portfolio securities to achieve its investment objective.The Portfolio’s assets normally are allocated among two portions, each of which is managed using a different but complementary investment strategy. One portion of the Portfolio is actively managed (“Active Allocated Portion”) and one portion of the Portfolio seeks to track the performance of a particular index (“Passive Allocated Portion”). Under normal circumstances, the Active Allocated Portion consists of approximately 30% of the Portfolio’s net assets and the Passive Allocated Portion consists of approximately 70% of the Portfolio’s net assets. These percentages are targets established by the Adviser; actual allocations may deviate from these targets.

The Active Allocated Portion may invest in debt securities of U.S. and foreign issuers, including issuers located in emerging markets. The Active Allocated Portion’s investments may include government securities, corporate bonds, bonds of foreign issuers (including those denominated in foreign currencies or U.S. dollars), commercial and residential mortgage-backed securities, and asset-backed securities. Foreign currency exposure (from

non-U.S.

dollar-denominated securities or currencies) normally will be limited to 10% of the Portfolio’s total assets. Securities are purchased for the Active Allocated Portion when a Sub-Adviser determines that they have the potential for above-average total return. A Sub-Adviser may sell a security for a variety of reasons, such as to make other investments believed by the Sub-Adviser to offer superior investment opportunities.

The Passive Allocated Portion of the Portfolio will invest in debt securities that are included in the Bloomberg Barclays U.S. Intermediate Government Bond Index (“Intermediate Government Bond Index”), or other financial instruments that derive their value from those securities. The Intermediate Government Bond Index is an unmanaged index that measures the performance of securities consisting of all U.S. Treasury and agency securities with remaining maturities of from one to ten years and issue amounts of at least $250 million outstanding, which may include zero-coupon securities.

Individual securities holdings may differ from the Intermediate Government Bond Index, and the Portfolio may not track the performance of the Intermediate Government Bond Index perfectly due to expenses and transaction costs, the size and frequency of cash flow into and out of the Portfolio, and differences between how and when the Portfolio and the Intermediate Government Bond Index are valued.

The Portfolio also may lend its portfolio securities to earn additional income.

Risk [Heading]

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Principal Risks:

Risk Narrative [Text Block]

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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. The value of your investment may fall, sometimes sharply, and you could lose money by investing in the Portfolio. There can be no assurance that the Portfolio will achieve its investment objective.

The following risks can negatively affect the Portfolio’s performance. The most significant risks as of the date of this Prospectus are listed first, followed by additional risks in alphabetical order.

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. Changes in the financial condition of a single issuer can impact a market as a whole. Geo-political risks, including terrorism, tensions or open conflict between nations, or political or economic dysfunction within some nations that are major players on the world stage, may lead to instability in world economies and markets, may lead to increased market volatility, and may have adverse long-term effects. Events such as natural disasters, public health crises (such as epidemics and pandemics) and social unrest, and governments’ reactions to such events, could cause uncertainty in the markets and may adversely affect the performance of the global economy. Adverse market conditions may not have the same impact on all types of securities. 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.

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, 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.

Interest Rate Risk:

Changes in interest rates may affect the yield, liquidity and value of investments in income producing or debt 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 or duration 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 with any increase in the duration of those securities. Very low or negative interest rates may magnify interest rate risk. A significant or rapid rise in interest rates also could result in losses to the Portfolio.

Government Securities Risk:

Not all obligations of the U.S. government, its agencies and instrumentalities are backed by the full faith and credit of the U.S. government. Some obligations are backed only by the credit of the issuing agency or instrumentality, and, in some cases, there may be some risk of default by the issuer. Any guarantee by the U.S. government or its agencies or instrumentalities of a security the Portfolio holds does not apply to the market value of the security or to shares of the Portfolio. A security backed by the U.S. Treasury or the full faith and credit of the U.S. government is guaranteed only as to the timely payment of interest and principal when held to maturity.

Investment Grade Securities Risk:

Securities rated in the lower investment grade rating categories (e.g., BBB or Baa) are considered investment grade securities, but are somewhat riskier than higher rated obligations because they are regarded as having only an adequate capacity to pay principal and interest, are considered to lack outstanding investment characteristics, and may possess certain speculative characteristics.

Index Strategy Risk:

The Portfolio (or a portion thereof) 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.

Derivatives Risk:

The Portfolio’s investments in derivatives may rise or fall in value more rapidly than other investments and may reduce the Portfolio’s returns and increase the volatility of the Portfolio’s net asset value. Investing in derivatives involves investment techniques and risk analyses different from, and risks in some respects greater than, those associated with investing in more traditional investments, such as stocks and bonds. Derivatives may be leveraged such that a small investment can have a significant impact on the Portfolio’s exposure to stock market values, interest rates, or other investments. As a result, a relatively small price movement in a derivatives contract may cause an immediate and substantial loss, and the Portfolio could lose more than the amount it invested. Some derivatives can have the potential for unlimited losses. In addition, it may be difficult or impossible for the Portfolio to purchase or sell certain derivatives in sufficient amounts to achieve the desired level of exposure, or to terminate or offset existing arrangements, which may result in a loss or may be costly to the Portfolio. Some derivatives are more sensitive to market price fluctuations and to interest rate changes than other investments. Derivatives may not behave as anticipated by the Portfolio, and derivatives strategies that are successful under certain market conditions may be less successful or unsuccessful under other market conditions. The Portfolio also may be exposed to losses if the counterparty in the transaction is unable or unwilling to fulfill its contractual obligation. In certain cases, the Portfolio may be hindered or delayed in exercising remedies against or closing out derivatives with a counterparty, resulting in additional losses. Derivatives also may be subject to the risk of mispricing or improper valuation. Derivatives can be difficult to value, and valuation may be more difficult in times of market turmoil. Changing regulation may make derivatives more costly, limit their availability, impact the Portfolio’s ability to maintain its investments in derivatives, disrupt markets, or otherwise adversely affect their value or performance.

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 trade barriers and other protectionist trade policies (including those of the U.S.), governmental instability, or other political or economic actions, also may adversely impact security values. World markets, or those in a particular region, may all react in similar fashion to important 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.

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.

Emerging Markets Risk:

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. 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. The risks associated with investments in emerging market countries often are significant, and vary from jurisdiction to jurisdiction and company to company.

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.

Leveraging Risk:

When the Portfolio leverages its holdings, the value of an investment in the Portfolio will be more volatile and all other risks will tend to be compounded. Investments that create leverage can result in losses to the Portfolio that exceed the amount originally invested and may accelerate the rate of losses (some of which may be sudden or substantial). For certain investments that create leverage, relatively small market fluctuations can result in large changes in the value of such investments. There can be no assurance that the Portfolio’s use of any leverage will be successful.

Liquidity Risk:

From time to time, there may be little or no active trading market for a particular investment in which the Portfolio may invest or is invested. In such a market, the value of such an investment and the Portfolio’s share price may fall dramatically. Illiquid investments may be difficult or impossible to sell or purchase at an advantageous time or price or in sufficient amounts to achieve the Portfolio’s desired level of exposure. To meet redemption requests during periods of illiquidity, the Portfolio may be forced to dispose of investments at unfavorable times or prices and/or under unfavorable conditions, which may result in a loss or may be costly to the Portfolio. Investments that are illiquid or that trade in lower volumes may be more difficult to value. The Portfolio also may not receive its proceeds from the sale of certain investments for an extended period of time. Certain investments that were liquid when purchased may later become illiquid, sometimes abruptly, particularly in times of overall economic distress or adverse investor perception. An inability to sell a portfolio position can adversely affect the Portfolio’s value or prevent the Portfolio from being able to take advantage of other investment opportunities. During periods of market stress, an investment or even an entire market segment may become illiquid, sometimes abruptly, which can adversely affect the Portfolio’s ability to limit losses. In addition, a reduction in the ability or willingness of dealers and other institutional investors to make a market in certain securities may result in decreased liquidity in certain markets.

Mortgage-Related and Other Asset-Backed Securities Risk:

Declines in the credit quality of and defaults by the issuers of mortgage-related and other asset-backed securities or instability in the markets for such securities may decrease the value of such securities, which could result in losses to the Portfolio, and may reduce the liquidity of such securities and make such securities more difficult to purchase or sell at an advantageous time and price. In addition, borrowers may default on the obligations that underlie mortgage-related and other asset-backed securities. The risk of defaults by borrowers generally is greater during times of rising interest rates and/or unemployment rates. The impairment (or loss) of the value of collateral or other assets underlying mortgage-related and other asset-backed securities will result in a reduction in the value of the securities. Certain collateral may be difficult to locate in the event of default, or may be lost, and recoveries of depreciated or damaged collateral may not fully cover payments due on such collateral. Asset-backed securities may not have the benefit of a security interest in collateral comparable to that of mortgage assets, resulting in additional credit risk.

In addition, certain mortgage-related and other asset-backed securities may include securities backed by pools of loans made to “subprime” borrowers or borrowers with blemished credit histories. The risk of defaults by borrowers is generally higher in the case of asset or mortgage pools that include subprime assets or mortgages, and the liquidity and value of subprime mortgages and non-investment grade mortgage-backed securities that are not guaranteed by Ginnie Mae, Fannie Mae, and Freddie Mac could change dramatically over time.

Furthermore, mortgage-related and other asset-backed securities typically provide the issuer with the right to prepay the security prior to maturity. During periods of rising interest rates, the rate of prepayments tends to decrease because

borrowers are less likely to prepay debt (such as mortgage debt or automobile loans). Slower than expected payments can extend the average lives of mortgage-related and other asset-backed securities, and this may “lock in” a below market interest rate and increase the security’s duration and interest rate sensitivity, which may increase the volatility of the security’s value and may lead to losses. During periods of falling interest rates, the rate of prepayments tends to increase because borrowers are more likely to pay off debt and refinance at the lower interest rates then available. Unscheduled prepayments shorten the average lives of mortgage-related and other asset-backed securities and may result in the Portfolio’s having to reinvest the proceeds of the prepayments at lower interest rates, thereby reducing the Portfolio’s income.

Multiple Sub-Adviser Risk:

To a significant extent, the Portfolio’s performance will depend on the success of the Adviser in allocating the Portfolio’s assets to Sub-Advisers and its selection and oversight of the Sub-Advisers. The Sub-Advisers’ investment strategies may not work together as planned, which could adversely affect the Portfolio’s performance. Because each Sub-Adviser directs the trading for its own portion of the Portfolio, and does not aggregate its transactions with those of the other Sub-Adviser, the Portfolio may incur higher brokerage costs than would be the case if a single Sub-Adviser were managing the entire Portfolio. In addition, while the Adviser seeks to allocate the Portfolio’s assets among the Portfolio’s Sub-Advisers in a manner that it believes is consistent with achieving the Portfolio’s investment objective(s), the Adviser is subject to conflicts of interest in allocating the Portfolio’s assets among Sub-Advisers, including affiliated Sub-Advisers, because the Adviser pays different fees to the Sub-Advisers and due to other factors that could impact the Adviser’s revenues and profits.

Portfolio Turnover Risk:

High portfolio turnover (generally, turnover in excess of 100% in any given fiscal year) may result in increased transaction costs to the Portfolio, which may result in higher fund expenses and lower total return.

Prepayment Risk and Extension Risk:

Prepayment risk is the risk that the issuer of a security held by the Portfolio may pay off principal more quickly than originally anticipated. This may occur when interest rates fall. The Portfolio may have to reinvest the proceeds in an investment offering a lower yield, may not benefit from any increase in value that might otherwise result from declining interest rates and may lose any premium it paid to acquire the security. Extension risk is the risk that the issuer of a security held by the Portfolio may pay off principal more slowly than originally anticipated. This may occur when interest rates rise. The Portfolio may be prevented from reinvesting the proceeds it would have received at a given time in an investment offering a higher yield.

Privately Placed and Other Restricted Securities Risk:

Restricted securities, which include privately placed securities, are securities that cannot be offered for public resale unless registered under the applicable securities laws or that have a contractual restriction that prohibits or limits their resale. Difficulty in selling securities may result in a loss or be costly to the Portfolio. The risk that securities may not be sold for the price at which the Portfolio is carrying them is greater with respect to restricted securities than it is with respect to registered securities. The illiquidity of the market, as well as the lack of publicly available information regarding these securities, also may make it difficult to determine a fair value for certain securities for purposes of computing the Portfolio’s net asset value.

Redemption Risk

The Portfolio may experience periods of heavy redemptions that could cause the Portfolio to sell assets at inopportune times or at a loss or depressed value. Redemption risk is heightened during periods of declining or illiquid markets. Heavy redemptions could hurt the Portfolio’s performance.

Market developments and other factors, including a general rise in interest rates, have the potential to cause investors to move out of fixed income securities on a large scale, which may increase redemptions from mutual funds that hold large amounts of fixed income securities. The market-making capacity of dealers has been reduced in recent years, in part as a result of structural changes, such as fewer proprietary trading desks at broker-dealers and increased regulatory capital requirements. In addition, significant securities market disruptions related to the coronavirus disease (COVID-19) pandemic have led to dislocation in the market for a variety of fixed income securities (including, without limitation, commercial paper, corporate debt securities, certificates of deposit, asset-backed debt securities and municipal obligations), which has decreased liquidity and sharply reduced returns in certain cases. Increased redemptions from mutual funds that hold large amounts of fixed income securities, coupled with a reduction in the ability or willingness of dealers and other institutional investors to buy or hold fixed income securities, may result in decreased liquidity and increased volatility in the fixed income markets.

Securities Lending Risk:

The Portfolio may lend its portfolio securities to seek income. There is a risk that a borrower may default on its obligations to return loaned securities. The Portfolio will be responsible for the risks associated with the investment of cash collateral and may lose money on its investment of cash collateral or may fail to earn sufficient income on its investment to meet obligations to the borrower. Securities lending may introduce leverage into the Portfolio. In addition, delays may occur in the recovery of loaned securities from borrowers, which could interfere with the Portfolio’s ability to vote proxies or to settle transactions.

When-Issued and Delayed Delivery Securities and Forward Commitments Risk:

When-issued and delayed delivery securities and forward commitments involve the risk that the security the Portfolio buys will decline in value prior to its delivery. This risk is in addition to the risk that the

Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. There also is the risk that the security will not be issued or that the other party to the transaction will not meet its obligation. If this occurs, the Portfolio may lose both the investment opportunity for the assets it set aside to pay for the security and any gain in the security’s price.

Zero Coupon and Pay-in-Kind Securities Risk:

A zero coupon or pay-in-kind security pays no interest in cash to its holder during its life. Accordingly, zero coupon securities usually trade at a deep discount from their face or par value and, together with pay-in-kind securities, will be subject to greater fluctuations in market value in response to changing interest rates than debt obligations of comparable maturities that make current distribution of interest in cash.

Risk Lose Money [Text]

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The value of your investment may fall, sometimes sharply, and you could lose money by investing in the Portfolio.

Risk Not Insured Depository Institution [Text]

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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.

Bar Chart and Performance Table [Heading]

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Risk/Return Bar Chart and Table

Performance Narrative [Text Block]

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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 (or since inception) through December 31, 2020 compared to the returns of a broad-based securities market index. The return of the broad-based securities market index (and any additional comparative index) shown in the right hand column below is the return of the index for the last 10 years or, if shorter, since the inception of the share class with the longest history. Past performance is not an indication of future performance. Prior to September 1, 2012, the Portfolio had a different investment strategy.

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]

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Performance Past Does Not Indicate Future [Text]

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Past performance is not an indication of future performance.

Bar Chart [Heading]

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Calendar Year Annual Total Returns — Class IB

Bar Chart Closing [Text Block]

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Best quarter (% and time period)		Worst quarter (% and time period)

3.82% (2020 1st Quarter)		–2.40% (2016 4th Quarter)

Performance Table Heading

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Average Annual Total Returns

EQ/Quality Bond PLUS Portfolio | Class IA Shares

Shareholder Fees (fees paid directly from your investment)

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Management Fee

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0.39%

Distribution and/or Service Fees (12b-1 fees)

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0.25%

Other Expenses

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0.16%

Total Annual Portfolio Operating Expenses

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0.80%

rr_ExpenseExampleYear01

$ 82

rr_ExpenseExampleYear03

255

rr_ExpenseExampleYear05

444

rr_ExpenseExampleYear10

990

rr_ExpenseExampleNoRedemptionYear01

rr_ExpenseExampleNoRedemptionYear03

255

rr_ExpenseExampleNoRedemptionYear05

444

rr_ExpenseExampleNoRedemptionYear10

$ 990

rr_AverageAnnualReturnYear01

5.96%

EQ/Quality Bond PLUS Portfolio | Class IB Shares

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2.81%

Ten Years

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1.89%

Shareholder Fees (fees paid directly from your investment)

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rr_ShareholderFeeOther

Management Fee

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0.39%

Distribution and/or Service Fees (12b-1 fees)

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0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.16%

Total Annual Portfolio Operating Expenses

rr_ExpensesOverAssets

0.80%

rr_ExpenseExampleYear01

$ 82

rr_ExpenseExampleYear03

255

rr_ExpenseExampleYear05

444

rr_ExpenseExampleYear10

990

rr_ExpenseExampleNoRedemptionYear01

rr_ExpenseExampleNoRedemptionYear03

255

rr_ExpenseExampleNoRedemptionYear05

444

Highest Quarterly Return, Label

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$ 990

2011

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1.16%

2012

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2.66%

2013

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(2.32%)

2014

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2.96%

2015

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0.16%

2016

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1.20%

2017

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1.34%

2018

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0.20%

2019

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5.62%

2020

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5.98%

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Best quarter

Highest Quarterly Return, Date

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Mar. 31, 2020

Highest Quarterly Return

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3.82%

Lowest Quarterly Return, Label

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Worst quarter

Lowest Quarterly Return, Date

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Dec. 31, 2016

Lowest Quarterly Return

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(2.40%)

rr_AverageAnnualReturnYear01

5.98%

EQ/Quality Bond PLUS Portfolio | Class K Shares

rr_AverageAnnualReturnYear05

2.84%

Ten Years

rr_AverageAnnualReturnYear10

1.87%

Shareholder Fees (fees paid directly from your investment)

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rr_ShareholderFeeOther

Management Fee

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0.39%

Distribution and/or Service Fees (12b-1 fees)

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none

Other Expenses

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0.16%

Total Annual Portfolio Operating Expenses

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0.55%

rr_ExpenseExampleYear01

$ 56

rr_ExpenseExampleYear03

176

rr_ExpenseExampleYear05

307

rr_ExpenseExampleYear10

689

rr_ExpenseExampleNoRedemptionYear01

rr_ExpenseExampleNoRedemptionYear03

176

rr_ExpenseExampleNoRedemptionYear05

307

rr_ExpenseExampleNoRedemptionYear10

$ 689

rr_AverageAnnualReturnYear01

6.22%

EQ/Quality Bond PLUS Portfolio | Bloomberg Barclays U.S. Intermediate Government Bond Index (reflects no deduction for fees, expenses, or taxes)

rr_AverageAnnualReturnYear05

3.09%

Since Inception

rr_AverageAnnualReturnSinceInception

2.68%

Inception Date

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Apr. 17, 2014

rr_RiskReturnAbstract

rr_AverageAnnualReturnYear01

5.73%