Label	Element	Value
Class I \| Short Duration Bond Portfolio
Risk/Return:	rr_RiskReturnAbstract
Objective [Heading]	rr_ObjectiveHeading	GOAL
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The Fund seeks the highest available current income consistent with liquidity and low risk to principal;
Objective, Secondary [Text Block]	rr_ObjectiveSecondaryTextBlock	total return is a secondary goal.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	These tables describe the fees and expenses that you may pay if you buy, hold or sell shares of the Fund. These tables do not reflect any fees and expenses charged by your insurance company under your variable contract or by your qualified plan. If the tables did reflect such fees and expenses, the overall expenses would be higher than those shown. Please refer to the prospectus for your variable contract or your qualified plan documentation for information on their separate fees and expenses.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder Fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses that you pay each year as a % of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio Turnover
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund 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 operating expenses or in the example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 91% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	91.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	Expense Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	The expense example can help you compare costs among mutual funds. The example assumes that you invested $10,000 for the periods shown, that you redeemed all of your shares at the end of those periods, that the Fund earned a hypothetical 5% total return each year, and that the Fund’s expenses were those in the table. Actual performance and expenses may be higher or lower.
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	To pursue its goals, the Fund invests mainly in fixed and floating rate investment-grade bonds and other debt securities issued by domestic and foreign governments, corporate entities, and trusts. These may include mortgage- and asset-backed securities, collateralized debt obligations (“CDOs”), including collateralized loan obligations (“CLOs”), and credit risk transfer securities. The Fund considers debt securities to be investment grade if, at the time of investment, they are rated within the four highest categories by at least one independent credit rating agency or, if unrated, are determined by the Portfolio Managers to be of comparable quality. The Portfolio Managers monitor trends in the corporate and government securities markets, as well as a range of economic and financial factors utilizing internally generated data that are produced by specialty sector investment teams in conjunction with asset allocation tools. If particular sectors of the bond market appear relatively inexpensive, the Portfolio Managers may increase the Fund’s exposure in those sectors and decrease exposure in other sectors. The Portfolio Managers look for securities that appear under-priced compared to securities of similar structure and credit quality. The Fund may sell securities if the Portfolio Managers find an opportunity they believe is more compelling or if the Portfolio Managers’ outlook on the investment or the market changes. To enhance yield and add diversification, the Fund may invest up to 20% of its net assets in securities that are below investment grade (commonly known as “junk bonds”). In choosing lower-rated securities, the Portfolio Managers generally look for bonds from issuers whose financial health appears comparatively strong, and that may have their credit ratings raised. The Fund does not normally invest in or continue to hold securities that are in default or have defaulted with respect to the payment of interest or repayment of principal, but may do so depending on market or other conditions. The Fund may invest in foreign securities, including obligations of issuers in emerging market countries, denominated in any currency, but the Fund normally will not invest more than 20% of its total assets at the time of investment in non-US dollar denominated securities. The Fund considers emerging market countries to be countries included in the JPMorgan Emerging Markets Bond Index - Global Diversified, the JPMorgan Corporate Emerging Markets Bond Index - Diversified, the JPMorgan Emerging Local Markets Index or the JPMorgan Government Bond Index - Emerging Markets Global Diversified, as well as those countries which are not defined as High Income Organization for Economic Cooperation and Development (OECD) member countries by the World Bank. The Fund may also invest in derivative instruments as a means of hedging risk and/or for investment purposes, which may include altering the Fund’s exposure to interest rates, currencies, sectors and individual issuers. These derivative instruments may include futures, forward foreign currency contracts, and swaps. The Fund may also invest a significant amount of its assets in U.S. Treasury securities or other money market instruments depending on market conditions. Additionally, the Fund may invest in restricted securities. The Fund may also engage in when-issued and forward-settling securities (such as to-be-announced (“TBA”) mortgage-backed securities), which involve a commitment by the Fund to purchase securities that will be issued or settled at a later date. The Fund seeks to reduce credit risk by diversifying among many issuers and different types of securities. As part of the investment process, the Portfolio Managers analyze individual issues (including an analysis of cash flows, ability to pay principal and interest, balance sheet composition, and market positioning). The Fund’s Portfolio Managers systematically evaluate material Environmental, Social and Governance (ESG) considerations as a factor in their investment analysis. The Portfolio Managers believe that ESG factors, like other more traditional subjects of investment analysis, have the potential to affect financial risk (e.g., an issuer’s overall credit profile) and investment returns. The Portfolio Managers conduct ongoing proprietary ESG research and proactively engage on ESG issues, supplemented by third-party ESG information, and use this as an input to the team’s internal credit ratings, which may be notched up or down depending on the ESG profile of an issuer. ESG considerations that the Portfolio Managers may consider include, but are not limited to: greenhouse gas emissions, data privacy and security, labor management, workforce diversity and inclusion, and business ethics, executive compensation and board composition. The consideration of ESG factors as part of the portfolio managers’ investment process does not mean that the Fund pursues a specific “impact” or “sustainable” investment strategy. Although it may invest in securities of any maturity, the Fund normally seeks to maintain an average portfolio duration of three years or less. The Fund may invest in other investment companies, including exchange-traded funds (“ETFs”), if the investment companies invest principally in the types of investments in which the Fund may invest directly. In an effort to achieve its goal, the Fund may engage in frequent and active trading. The Fund normally invests at least 80% of its net assets in bonds and other debt securities and other investment companies that provide investment exposure to such debt securities. The Fund will not alter this policy without providing shareholders at least 60 days’ notice. This test is applied at the time the Fund invests; later percentage changes caused by a change in Fund assets, market values or company circumstances will not require the Fund to dispose of a holding.
Risk [Heading]	rr_RiskHeading	PRINCIPAL INVESTMENT RISKS
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	Most of the Fund’s performance depends on what happens in the market for debt instruments, the Portfolio Managers' evaluation of those developments, and the success of the Portfolio Managers in implementing the Fund's investment strategies. The Fund’s use of derivative instruments will result in leverage, which amplifies the risks that are associated with these markets. The market's behavior can be difficult to predict, particularly in the short term. There can be no guarantee that the Fund will achieve its goal. The Fund may take temporary defensive and cash management positions; to the extent it does, it will not be pursuing its principal investment strategies. The actual risk exposure taken by the Fund in its investment program will vary over time, depending on various factors including the Portfolio Managers' evaluation of issuer, political, regulatory, market, or economic developments. There can be no guarantee that the Portfolio Managers will be successful in their attempts to manage the risk exposure of the Fund or will appropriately evaluate or weigh the multiple factors involved in investment decisions, including issuer, market and/or instrument-specific analysis, valuation and environmental, social and governance factors. The Fund is a mutual fund, not a bank deposit, and is not guaranteed or insured 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 Fund. While this Fund may have a shorter duration than many other income funds, this Fund is not intended to operate like a money market fund. Each of the following risks, which are described in alphabetical order and not in order of any presumed importance, can significantly affect the Fund’s performance. The relative importance of, or potential exposure as a result of, each of these risks will vary based on market and other investment-specific considerations. Call Risk. Upon the issuer’s desire to call a security, or under other circumstances where a security is called, including when interest rates are low and issuers opt to repay the obligation underlying a “callable security” early, the Fund may have to reinvest the proceeds in an investment offering a lower yield and may not benefit from any increase in value that might otherwise result from declining interest rates. Collateralized Debt Obligations Risk. CDOs, which include collateralized loan obligations (CLOs), issue classes or “tranches” of securities that vary in risk and yield and may experience substantial losses due to interest rate fluctuations, actual defaults, collateral defaults, disappearance of subordinate tranches, market anticipation of defaults, and investor aversion to CDO securities as a class. The risks of investing in CDOs depend largely on the quality and type of the underlying debt, which may include loans, bonds and mortgages, and the tranche of the CDO in which the Fund invests. In addition, CDOs that obtain their exposure through derivative instruments entail the additional risks associated with such instruments. CDOs can be difficult to value, may at times be illiquid, may be highly leveraged (which could make them highly volatile), and may produce unexpected investment results due to their complex structure. In addition, CDOs involve many of the same risks of investing in debt securities and asset-backed securities including, but not limited to, interest rate risk, credit risk, liquidity risk, and valuation risk. Credit Risk. Credit risk is the risk that issuers, guarantors, or insurers may fail, or become less able or unwilling, to pay interest and/or principal when due. Changes in the actual or perceived creditworthiness of an issuer, or a downgrade or default affecting any of the Fund’s securities could affect the Fund’s performance. Generally, the longer the maturity and the lower the credit quality of a security, the more sensitive it is to credit risk. Currency Risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar. To the extent that the Fund invests in securities or other instruments denominated in or indexed to foreign currencies, changes in currency exchange rates could adversely impact investment gains or add to investment losses. Currency exchange rates may fluctuate significantly over short periods of time and can be affected unpredictably by various factors, including investor perception and changes in interest rates; intervention, or failure to intervene, by U.S. or foreign governments, central banks, or supranational entities; or by currency controls or political developments in the U.S. or abroad. Derivatives Risk. Use of derivatives is a highly specialized activity that can involve investment techniques and risks different from, and in some respects greater than, those associated with investing in more traditional investments, such as stocks and bonds. Derivatives can be highly complex and highly volatile and may perform in unanticipated ways. Derivatives can create leverage, and the Fund could lose more than the amount it invests; some derivatives can have the potential for unlimited losses. Derivatives may at times be highly illiquid, and the Fund may not be able to close out or sell a derivative at a particular time or at an anticipated price. Derivatives can be difficult to value and valuation may be more difficult in times of market turmoil. The value of a derivative instrument depends largely on (and is derived from) the value of the reference instrument underlying the derivative. There may be imperfect correlation between the behavior of a derivative and that of the reference instrument underlying the derivative. An abrupt change in the price of a reference instrument could render a derivative worthless. Derivatives may involve risks different from, and possibly greater than, the risks associated with investing directly in the reference instrument. Suitable derivatives may not be available in all circumstances, and there can be no assurance that the Fund will use derivatives to reduce exposure to other risks when that might have been beneficial. Derivatives involve counterparty risk, which is the risk that the other party to the derivative will fail to make required payments or otherwise comply with the terms of the derivative. That risk is generally thought to be greater with over-the-counter (OTC) derivatives than with derivatives that are exchange traded or centrally cleared. When the Fund uses derivatives, it will likely be required to provide margin or collateral and/or segregate cash or other liquid assets; these practices are intended to satisfy contractual undertakings and regulatory requirements and will not prevent the Fund from incurring losses on derivatives. The need to provide margin or collateral and/or segregate assets could limit the Fund's ability to pursue other opportunities as they arise. Ongoing changes to regulation of the derivatives markets and actual and potential changes in the regulation of funds using derivative instruments could limit the Fund’s ability to pursue its investment strategies. New regulation of derivatives may make them more costly, or may otherwise adversely affect their liquidity, value or performance. Additional risks associated with certain types of derivatives are discussed below: Forward Contracts. There are no limitations on daily price movements of forward contracts. Changes in foreign exchange regulations by governmental authorities might limit the trading of forward contracts on currencies. Futures. Futures contracts are subject to the risk that an exchange may impose price fluctuation limits, which may make it difficult or impossible for a fund to close out a position when desired. In the absence of such limits, the liquidity of the futures market depends on participants entering into offsetting transactions rather than taking or making delivery. To the extent a Fund enters into futures contracts requiring physical delivery (e.g., certain commodities contracts), the inability of the Fund to take or make physical delivery can negatively impact performance. Swaps. The risk of loss with respect to swaps generally is limited to the net amount of payments that the Fund is contractually obligated to make or, in the case of the other party to a swap defaulting, the net amount of payments that the Fund is contractually entitled to receive. If the Fund sells a credit default swap, however, the risk of loss may be the entire notional amount of the swap. Some swaps are now executed through an organized exchange or regulated facility and cleared through a regulated clearing organization. The absence of an organized exchange or market for swap transactions may result in difficulties in trading and valuation, especially in the event of market disruptions. The use of an organized exchange or market for swap transactions is expected to result in swaps being easier to trade or value, but this may not always be the case. Foreign and Emerging Market Risk. Foreign securities, including those issued by foreign governments, involve risks in addition to those associated with comparable U.S. securities. Additional risks include exposure to less developed or less efficient trading markets; social, political, diplomatic, or economic instability; trade barriers and other protectionist trade policies (including those of the U.S.); significant government involvement in an economy and/or market structure; fluctuations in foreign currencies or currency redenomination; potential for default on sovereign debt; nationalization or expropriation of assets; settlement, custodial or other operational risks; higher transaction costs; confiscatory withholding or other taxes; and less stringent auditing, corporate disclosure, governance, and legal standards. As a result, foreign securities may fluctuate more widely in price, and may also be less liquid, than comparable U.S. securities. Regardless of where a company is organized or its stock is traded, its performance may be affected significantly by events in regions from which it derives its profits or in which it conducts significant operations. Investing in emerging market countries involves risks in addition to and greater than those generally associated with investing in more developed foreign countries. The governments of emerging market countries may be more unstable and more likely to impose capital controls, nationalize a company or industry, place restrictions on foreign ownership and on withdrawing sale proceeds of securities from the country, intervene in the financial markets, and/or impose burdensome taxes that could adversely affect security prices. To the extent a foreign security is denominated in U.S. dollars, there is also the risk that a foreign government will not let U.S. dollar-denominated assets leave the country. In addition, the economies of emerging market countries may be dependent on relatively few industries that are more susceptible to local and global changes. Emerging market countries may also have less developed legal and accounting systems, and their legal systems may deal with issuer bankruptcies and defaults differently than U.S. law would. Securities markets in emerging market countries are also relatively small and have substantially lower trading volumes. Securities of issuers in emerging market countries may be more volatile and less liquid than securities of issuers in foreign countries with more developed economies or markets and the situation may require that the Fund fair value its holdings in those countries. Securities of issuers traded on foreign exchanges may be suspended, either by the issuers themselves, by an exchange, or by governmental authorities. The likelihood of such suspensions may be higher for securities of issuers in emerging or less-developed market countries than in countries with more developed markets. Trading suspensions may be applied from time to time to the securities of individual issuers for reasons specific to that issuer, or may be applied broadly by exchanges or governmental authorities in response to market events. Suspensions may last for significant periods of time, during which trading in the securities and in instruments that reference the securities, such as derivative instruments, may be halted. In the event that the Fund holds material positions in such suspended securities or instruments, the Fund’s ability to liquidate its positions or provide liquidity to investors may be compromised and the Fund could incur significant losses. High Portfolio Turnover. The Fund may engage in active and frequent trading and may have a high portfolio turnover rate, which may increase the Fund’s transaction costs and may adversely affect the Fund’s performance. Interest Rate Risk.The Fund’s yield and share price will fluctuate in response to changes in interest rates. In general, the value of investments with interest rate risk, such as debt securities, will move in the direction opposite to movements in interest rates. If interest rates rise, the value of such securities may decline. 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 Fund’s debt securities to interest rate risk will increase with any increase in the duration of those securities. Issuer-Specific Risk. An individual security may be more volatile, and may perform differently, than the market as a whole. Leverage Risk. Leverage amplifies changes in the Fund’s net asset value and may make the Fund more volatile. Derivatives and when-issued and forward-settling securities may create leverage and can result in losses to the Fund that exceed the amount originally invested and may accelerate the rate of losses. There can be no assurance that the Fund’s use of any leverage will be successful. The Fund’s investment exposure can exceed its net assets, sometimes by a significant amount. Liquidity Risk. From time to time, the trading market for a particular investment in which the Fund invests, or a particular type of instrument in which the Fund is invested, may become less liquid or even illiquid. Illiquid investments frequently can be more difficult to purchase or sell at an advantageous price or time, and there is a greater risk that the investments may not be sold for the price at which the Fund is carrying them. Certain investments that were liquid when the Fund purchased them may become illiquid, sometimes abruptly. Additionally, market closures due to holidays or other factors may render a security or group of securities (e.g., securities tied to a particular country or geographic region) illiquid for a period of time. An inability to sell a portfolio position can adversely affect the Fund’s value or prevent the Fund from being able to take advantage of other investment opportunities. Market prices for such securities or other investments may be volatile. During periods of substantial market volatility, an investment or even an entire market segment may become illiquid, sometimes abruptly, which can adversely affect the Fund’s ability to limit losses. Unexpected episodes of illiquidity, including due to market or political factors, instrument or issuer-specific factors and/or unanticipated outflows, may limit the Fund’s ability to pay redemption proceeds within the allowable time period. To meet redemption requests during periods of illiquidity, the Fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions. Lower-Rated Debt Securities Risk. Lower-rated debt securities (commonly known as “junk bonds”) and unrated debt securities determined to be of comparable quality involve greater risks than investment grade debt securities. Such securities may fluctuate more widely in price and yield and may fall in price during times when the economy is weak or is expected to become weak. These securities also may require a greater degree of judgment to establish a price and may be difficult to sell at the time and price the Fund desires. Lower-rated debt securities are considered by the major rating agencies to be predominantly speculative with respect to the issuer’s continuing ability to pay principal and interest and carry a greater risk that the issuer of such securities will default in the timely payment of principal and interest. Issuers of securities that are in default or have defaulted may fail to resume principal or interest payments, in which case the Fund may lose its entire investment. The creditworthiness of issuers of these securities may be more complex to analyze than that of issuers of investment grade debt securities, and the overreliance on credit ratings may present additional risks. Market Volatility Risk. Markets may be volatile and values of individual securities and other investments, including those of a particular type, may decline significantly in response to adverse issuer, political, regulatory, market, economic or other developments that may cause broad changes in market value, public perceptions concerning these developments, and adverse investor sentiment or publicity. Geopolitical and other risks, including environmental and public health risks may add to instability in world economies and markets generally. Changes in value may be temporary or may last for extended periods. If the Fund sells a portfolio position before it reaches its market peak, it may miss out on opportunities for better performance. Mortgage- and Asset-Backed Securities Risk. The value of mortgage- and asset-backed securities, including collateralized mortgage instruments, will be influenced by the factors affecting the housing market or the assets underlying the securities. These securities tend to be more sensitive to changes in interest rates than other types of debt securities. In addition, investments in mortgage- and asset-backed securities may be subject to prepayment risk and extension risk, call risk, credit risk, valuation risk, and illiquid investment risk, sometimes to a higher degree than various other types of debt securities. These securities are also subject to the risk of default on the underlying mortgages or assets, particularly during periods of market downturn, and an unexpectedly high rate of defaults on the underlying assets will adversely affect the security’s value. Other Investment Company Risk. To the extent the Fund invests in other investment companies, including money market funds and exchange-traded funds (ETFs), its performance will be affected by the performance of those other investment companies. Investments in other investment companies are subject to the risks of the other investment companies’ investments, as well as to the other investment companies’ expenses. An ETF may trade in the secondary market at a price below the value of its underlying portfolio and may not be liquid. An actively managed ETF’s performance will reflect its adviser’s ability to make investment decisions that are suited to achieving the ETF’s investment objectives. A passively managed ETF may not replicate the performance of the index it intends to track. Prepayment and Extension Risk. The Fund’s performance could be affected if borrowers pay back principal on certain debt securities, such as mortgage- or asset-backed securities, before (prepayment) or after (extension) the market anticipates such payments, shortening or lengthening their duration. Due to a decline in interest rates or an excess in cash flow into the issuer, a debt security might be called or otherwise converted, prepaid or redeemed before maturity. As a result of prepayment, the Fund 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. Conversely, rising market interest rates generally result in slower payoffs or extension, which effectively increases the duration of certain debt securities, heightening interest rate risk and increasing the magnitude of any resulting price declines. Private Placements and Other Restricted Securities Risk. Private placements and other restricted securities, including securities for which Fund management has material non-public information, are securities that are subject to legal and/or contractual restrictions on their sales. These securities may not be sold to the public unless certain conditions are met, which may include registration under the applicable securities laws. As a result of the absence of a public trading market, the prices of these securities may be more difficult to determine than publicly traded securities and these securities may involve heightened risk as compared to investments in securities of publicly traded companies. Private placements and other restricted securities may be illiquid, and it frequently can be difficult to sell them at a time when it may otherwise be desirable to do so or the Fund may be able to sell them only at prices that are less than what the Fund regards as their fair market value. Transaction costs may be higher for these securities. In addition, the Fund may get only limited information about the issuer of a private placement or other restricted security. Recent Market Conditions. National economies are substantially interconnected, as are global financial markets, which creates the possibility that conditions in one country or region might adversely impact issuers in a different country or region. Some countries, including the U.S., have in recent years adopted more protectionist trade policies. The rise in protectionist trade policies, changes to some major international trade agreements and the potential for changes to others, could affect the economies of many nations in ways that cannot necessarily be foreseen at the present time. Markets have been sensitive to the outlook for resolving the U.S.-China “trade war,” a trend that may continue in the future. Russia’s assertion of its influence in its surrounding region, including potential actions in Ukraine, increases the likelihood of additional sanctions by the U.S. and other countries, which may cause volatility in the markets. High public debt in the U.S. and other countries creates ongoing systemic and market risks and policymaking uncertainty, and there may be a further increase in public debt due to the economic effects of the COVID-19 pandemic and ensuing economic relief and public health measures. Governments and central banks have moved to limit the potential negative economic effects of the COVID-19 pandemic with interventions that are unprecedented in size and scope and may continue to do so, but the ultimate impact of these efforts is uncertain. Governments’ efforts to limit potential negative economic effects of the pandemic may be altered, delayed, or eliminated at inopportune times for political, policy or other reasons. Interest rates have been unusually low in recent years in the U.S. and abroad. It is difficult to predict the impact on various markets of a significant rate increase or other significant policy changes, perhaps in response to indications of increasing inflation. Over the longer term, rising interest rates may present a greater risk than has historically been the case due to the current period of relatively low rates and the effect of government fiscal and monetary policy initiatives and potential market reaction to those initiatives or their alteration or cessation. The impact of the pandemic has negatively affected and may continue to affect the economies of many nations, individual companies and the global securities and commodities markets, including their liquidity, in ways that cannot necessarily be foreseen at the present time. The pandemic has accelerated trends toward working remotely and shopping on-line, which may negatively affect the value of office and commercial real estate and companies that have been slow to transition to an on-line business model, and has disrupted the supply chains that many businesses depend on. The travel, hospitality and public transit industries may suffer long-term negative effects from the pandemic and resulting changes to public behavior. Over the past several years, the U.S. has moved away from tighter industry regulation, a trend that appears to be changing. Increased regulation may impose added costs on the Fund and its service providers for monitoring and compliance, and affect the businesses of various portfolio companies, in ways that cannot necessarily be foreseen at the present time. Climate Change. There is widespread concern about the potential effects of global climate change on property and security values. A rise in sea levels, a change in weather patterns, including an increase in powerful storms and large wildfires, and/or a climate-driven increase in flooding could cause properties to lose value or become unmarketable altogether. Unlike previous declines in the real estate market, properties in affected zones may not ever recover their value. The U.S. administration appears concerned about the climate change problem and is focusing regulatory and public works projects around those concerns. Regulatory changes tied to concerns about climate change could adversely affect the value of certain land and the viability of certain industries. Losses related to climate change could adversely affect corporate issuers and mortgage lenders, the value of mortgage-backed securities, the bonds of municipalities that depend on tax or other revenues and tourist dollars generated by affected properties, and insurers of the property and/or of corporate, municipal or mortgage-backed securities. Since property and security values are driven largely by buyers’ perceptions, it is difficult to know the time period over which these market effects might unfold. LIBOR Transition. Certain financial contracts around the world specify rates that are based on the London Interbank Offered Rate (LIBOR), which is produced daily by averaging the rates for inter-bank lending reported by a number of banks. As previously announced by the United Kingdom’s Financial Conduct Authority, most maturities and currencies of LIBOR were phased out at the end of 2021, with the remaining ones to be phased out on June 30, 2023. There are risks that the financial services industry will not have a suitable substitute in place by that time and that there will not be time to perform the substantial work necessary to revise the many existing contracts that rely on LIBOR. The transition process, or a failure of the industry to transition properly, might lead to increased volatility and illiquidity in markets that currently rely on LIBOR. It also could lead to a reduction in the value of some LIBOR-based investments and reduce the effectiveness of new hedges placed against existing LIBOR-based instruments. New York has passed legislation to ease the transition from LIBOR and federal LIBOR transition relief legislation has been proposed, but there is no assurance whether or when such legislation will be enacted or if it will adequately address all issues or be subject to litigation. Redemption Risk. The Fund may experience periods of large or frequent redemptions that could cause the Fund to sell assets at inopportune times, which could have a negative impact on the Fund’s overall liquidity, or at a loss or depressed value. Redemption risk is greater to the extent that one or more investors or intermediaries control a large percentage of investments in the Fund and the risk is heightened during periods of declining or illiquid markets. Large redemptions could hurt the Fund’s performance, increase transaction costs, and create adverse tax consequences. A general rise in interest rates has 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; such a move, 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. Sector Risk. From time to time, based on market or economic conditions, the Fund may have significant positions in one or more sectors of the market. To the extent the Fund 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 or regulatory events. Sovereign Debt Risk. Sovereign debt securities are subject to the risk that a governmental entity may delay or refuse to pay interest or principal on its sovereign debt, due, for example, to cash flow problems, insufficient foreign currency reserves, political considerations, the size of the governmental entity’s debt position in relation to the economy, its policy toward international lenders or the failure to put in place economic reforms required by multilateral agencies. If a governmental entity defaults, it may ask for more time in which to pay or for further loans. There may be no legal process for collecting sovereign debt that a government does not pay nor are there bankruptcy proceedings through which all or part of the sovereign debt that a governmental entity has not repaid may be collected. Sovereign debt risk is increased for emerging market issuers. U.S. Government Securities Risk. Although the Fund may hold securities that carry U.S. government guarantees, these guarantees do not extend to shares of the Fund itself and do not guarantee the market prices of the securities. Furthermore, not all securities issued by the U.S. government and its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Securities not backed by the full faith and credit of the U.S. Treasury carry at least some risk of non-payment or default. Variable and Floating Rate Instruments Risk. The market prices of instruments with variable and floating interest rates are generally less sensitive to interest rate changes than are the market prices of instruments with fixed interest rates. Variable and floating rate instruments may decline in value if market interest rates or interest rates paid by such instruments do not move as expected. Certain types of floating rate instruments, such as interests in bank loans, may be subject to greater liquidity risk than other debt securities. When-Issued and Forward-Settling Securities Risk. When-issued and forward-settling securities can have a leverage-like effect on the Fund, which can increase fluctuations in the Fund’s share price; may cause the Fund to liquidate positions when it may not be advantageous to do so, in order to satisfy its purchase obligations; and are subject to the risk that the security will not be issued or that a counterparty will fail to complete the sale or purchase of the security, in which case the Fund may lose the opportunity to purchase or sell the security at the agreed upon price. A summary of the Fund’s additional principal investment risks is as follows: Risk of Increase in Expenses. A decline in the Fund’s average net assets during the current fiscal year due to market volatility or other factors could cause the Fund’s expenses for the current fiscal year to be higher than the expense information presented in “Fees and Expenses.” Operational and Cybersecurity Risk. The Fund and its service providers, and your ability to transact with the Fund, may be negatively impacted due to operational matters arising from, among other problems, human errors, systems and technology disruptions or failures, or cybersecurity incidents. Cybersecurity incidents may allow an unauthorized party to gain access to fund assets, customer data, or proprietary information, or cause the Fund or its service providers, as well as the securities trading venues and their service providers, to suffer data corruption or lose operational functionality. Cybersecurity incidents can result from deliberate attacks or unintentional events. It is not possible for the Manager or the other Fund service providers to identify all of the cybersecurity or other operational risks that may affect the Fund or to develop processes and controls to completely eliminate or mitigate their occurrence or effects. Most issuers in which the Fund invests are heavily dependent on computers for data storage and operations, and require ready access to the internet to conduct their business. Thus, cybersecurity incidents could also affect issuers of securities in which the Fund invests, leading to significant loss of value. Risk Management. Risk is an essential part of investing. No risk management program can eliminate the Fund’s exposure to adverse events; at best, it may only reduce the possibility that the Fund will be affected by such events, and especially those risks that are not intrinsic to the Fund’s investment program. The Fund could experience losses if judgments about risk prove to be incorrect. Valuation Risk. The Fund may not be able to sell an investment at the price at which the Fund has valued the investment. Such differences could be significant, particularly for illiquid securities and securities that trade in relatively thin markets and/or markets that experience extreme volatility. If market or other conditions make it difficult to value some investments, SEC rules and applicable accounting protocols may require the Fund to value these investments using more subjective methods, known as fair value methodologies. Using fair value methodologies to price investments may result in a value that is different from an investment’s most recent price and from the prices used by other mutual funds to calculate their NAVs. The Fund’s ability to value its investments in an accurate and timely manner may be impacted by technological issues and/or errors by third party service providers, such as pricing services or accounting agents.
Risk Lose Money [Text]	rr_RiskLoseMoney	The value of your investment may fall, sometimes sharply, and you could lose money by investing in the Fund.
RIsk Not Insured [Text]	rr_RiskNotInsured	The Fund is a mutual fund, not a bank deposit, and is not guaranteed or insured by the Federal Deposit Insurance Corporation or any other government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	PERFORMANCE
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The following bar chart and table provide an indication of the risks of investing in the Fund. The bar chart shows how the Fund’s performance has varied from year to year. The table below the bar chart shows what the returns would equal if you averaged out actual performance over various lengths of time and compares the returns with the returns of a broad-based market index. The index, which is described in “Description of Index” in the prospectus, has characteristics relevant to the Fund's investment strategy. The performance information does not reflect variable contract or qualified plan fees and expenses. If such fees and expenses were reflected, returns would be less than those shown. Please refer to the prospectus for your variable contract or your qualified plan documentation for information on their separate fees and expenses. Returns would have been lower if Neuberger Berman Investment Advisers LLC had not reimbursed certain expenses and/or waived a portion of the investment management fees during certain of the periods shown. Past performance is not a prediction of future results. Visit www.nb.com or call 800-877-9700 for updated performance information.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart shows how the Fund’s performance has varied from year to year. The table below the bar chart shows what the returns would equal if you averaged out actual performance over various lengths of time and compares the returns with the returns of a broad-based market index.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	800-877-9700
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	www.nb.com
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	Past performance is not a prediction of future results.
Bar Chart [Heading]	rr_BarChartHeading	year-by-year % Returns as of 12/31 each year
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best quarter: Q2 '20, 5.25% Worst quarter: Q1 '20, -4.54%
Performance Table Heading	rr_PerformanceTableHeading	average annual total % returns as of 12/31/21
Index No Deduction for Fees, Expenses, Taxes [Text]	rr_IndexNoDeductionForFeesExpensesTaxes	(reflects no deduction for fees, expenses or taxes)
Average Annual Return, Caption	rr_AverageAnnualReturnCaption	Short Duration Bond Portfolio
Class I \| Short Duration Bond Portfolio \| Bloomberg 1-3 Year U.S. Government/Credit Bond Index (reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	(0.47%)
5 Years	rr_AverageAnnualReturnYear05	1.85%
10 Years	rr_AverageAnnualReturnYear10	1.39%
Class I \| Short Duration Bond Portfolio \| Class I
Risk/Return:	rr_RiskReturnAbstract
Shareholder Fees (fees paid directly from your investment)	rr_ShareholderFeeOther	none
Management fees	rr_ManagementFeesOverAssets	0.57%
Distribution and/or shareholder service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	0.23%
Acquired fund fees and expenses	rr_AcquiredFundFeesAndExpensesOverAssets	0.03%
Total annual operating expenses	rr_ExpensesOverAssets	0.83%
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	$ 85
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	265
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	460
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	$ 1,025
Annual Return 2012	rr_AnnualReturn2012	4.61%
Annual Return 2013	rr_AnnualReturn2013	0.62%
Annual Return 2014	rr_AnnualReturn2014	0.61%
Annual Return 2015	rr_AnnualReturn2015	0.18%
Annual Return 2016	rr_AnnualReturn2016	1.22%
Annual Return 2017	rr_AnnualReturn2017	0.89%
Annual Return 2018	rr_AnnualReturn2018	1.02%
Annual Return 2019	rr_AnnualReturn2019	3.69%
Annual Return 2020	rr_AnnualReturn2020	3.46%
Annual Return 2021	rr_AnnualReturn2021	0.74%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Jun. 30, 2020
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	5.25%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Mar. 31, 2020
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(4.54%)
1 Year	rr_AverageAnnualReturnYear01	0.74%
5 Years	rr_AverageAnnualReturnYear05	1.95%
10 Years	rr_AverageAnnualReturnYear10	1.69%

Risk/Return:

rr_RiskReturnAbstract

rr_ObjectivePrimaryTextBlock

The Fund seeks the highest available current income consistent with liquidity and low risk to principal;

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Shareholder Fees Caption [Text]

rr_ShareholderFeesCaption

Shareholder Fees (fees paid directly from your investment)

Portfolio Turnover [Heading]

rr_PortfolioTurnoverHeading

Portfolio Turnover

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

91.00%

Expense Example Narrative [Text Block]

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The expense example can help you compare costs among mutual funds. The example assumes that you invested $10,000 for the periods shown, that you redeemed all of your shares at the end of those periods, that the Fund earned a hypothetical 5% total return each year, and that the Fund’s expenses were those in the table. Actual performance and expenses may be higher or lower.

Strategy Narrative [Text Block]

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To pursue its goals, the Fund invests mainly in fixed and floating rate investment-grade bonds and other debt securities issued by domestic and foreign governments, corporate entities, and trusts. These may include mortgage- and asset-backed securities, collateralized debt obligations (“CDOs”), including collateralized loan obligations (“CLOs”), and credit risk transfer securities. The Fund considers debt securities to be investment grade if, at the time of investment, they are rated within the four highest categories by at least one independent credit rating agency or, if unrated, are determined by the Portfolio Managers to be of comparable quality.

The Portfolio Managers monitor trends in the corporate and government securities markets, as well as a range of economic and financial factors utilizing internally generated data that are produced by specialty sector investment teams in conjunction with asset allocation tools. If particular sectors of the bond market appear relatively inexpensive, the Portfolio Managers may increase the Fund’s exposure in those sectors and decrease exposure in other sectors. The Portfolio Managers look for securities that appear under-priced compared to securities of similar structure and credit quality. The Fund may sell securities if the Portfolio Managers find an opportunity they believe is more compelling or if the Portfolio Managers’ outlook on the investment or the market changes.

To enhance yield and add diversification, the Fund may invest up to 20% of its net assets in securities that are below investment grade (commonly known as “junk bonds”). In choosing lower-rated securities, the Portfolio Managers generally look for bonds from issuers whose financial health appears comparatively strong, and that may have their credit ratings raised. The Fund does not normally invest in or continue to hold securities that are in default or have defaulted with respect to the payment of interest or repayment of principal, but may do so depending on market or other conditions.

The Fund may invest in foreign securities, including obligations of issuers in emerging market countries, denominated in any currency, but the Fund normally will not invest more than 20% of its total assets at the time of investment in non-US dollar denominated securities. The Fund considers emerging market countries to be countries included in the JPMorgan Emerging Markets Bond Index - Global Diversified, the JPMorgan Corporate Emerging Markets Bond Index - Diversified, the JPMorgan Emerging Local Markets Index or the JPMorgan Government Bond Index - Emerging Markets Global Diversified, as well as those countries which are not defined as High Income Organization for Economic Cooperation and Development (OECD) member countries by the World Bank.

The Fund may also invest in derivative instruments as a means of hedging risk and/or for investment purposes, which may include altering the Fund’s exposure to interest rates, currencies, sectors and individual issuers. These derivative instruments may include futures, forward foreign currency contracts, and swaps.

The Fund may also invest a significant amount of its assets in U.S. Treasury securities or other money market instruments depending on market conditions. Additionally, the Fund may invest in restricted securities. The Fund may also engage in when-issued and forward-settling securities (such as to-be-announced (“TBA”) mortgage-backed securities), which involve a commitment by the Fund to purchase securities that will be issued or settled at a later date.

The Fund seeks to reduce credit risk by diversifying among many issuers and different types of securities. As part of the investment process, the Portfolio Managers analyze individual issues (including an analysis of cash flows, ability to pay principal and interest, balance sheet composition, and market positioning). The Fund’s Portfolio Managers systematically evaluate material Environmental, Social and Governance (ESG) considerations as a factor in their investment analysis. The Portfolio Managers believe that ESG factors, like other more traditional subjects of investment analysis, have the potential to affect financial risk (e.g., an issuer’s overall credit profile) and investment returns. The Portfolio Managers conduct ongoing proprietary ESG research and proactively engage on ESG issues, supplemented by third-party ESG information, and use this as an input to the team’s internal credit ratings, which may be notched up or down depending on the ESG profile of an issuer. ESG considerations that the Portfolio Managers may consider include, but are not limited to: greenhouse gas emissions, data privacy and security, labor management, workforce diversity and inclusion, and business ethics, executive compensation and board composition. The consideration of ESG factors as part of the portfolio managers’ investment process does not mean that the Fund pursues a specific “impact” or “sustainable” investment strategy. Although it may invest in securities of any maturity, the Fund normally seeks to maintain an average portfolio duration of three years or less.

The Fund may invest in other investment companies, including exchange-traded funds (“ETFs”), if the investment companies invest principally in the types of investments in which the Fund may invest directly.

In an effort to achieve its goal, the Fund may engage in frequent and active trading.

The Fund normally invests at least 80% of its net assets in bonds and other debt securities and other investment companies that provide investment exposure to such debt securities. The Fund will not alter this policy without providing shareholders at least 60 days’ notice. This test is applied at the time the Fund invests; later percentage changes caused by a change in Fund assets, market values or company circumstances will not require the Fund to dispose of a holding.

Risk Narrative [Text Block]

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Most of the Fund’s performance depends on what happens in the market for debt instruments, the Portfolio Managers' evaluation of those developments, and the success of the Portfolio Managers in implementing the Fund's investment strategies. The Fund’s use of derivative instruments will result in leverage, which amplifies the risks that are associated with these markets. The market's behavior can be difficult to predict, particularly in the short term. There can be no guarantee that the Fund will achieve its goal. The Fund may take temporary defensive and cash management positions; to the extent it does, it will not be pursuing its principal investment strategies.

The actual risk exposure taken by the Fund in its investment program will vary over time, depending on various factors including the Portfolio Managers' evaluation of issuer, political, regulatory, market, or economic developments. There can be no guarantee that the Portfolio Managers will be successful in their attempts to manage the risk exposure of the Fund or will appropriately

evaluate or weigh the multiple factors involved in investment decisions, including issuer, market and/or instrument-specific analysis, valuation and environmental, social and governance factors.

The Fund is a mutual fund, not a bank deposit, and is not guaranteed or insured 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 Fund. While this Fund may have a shorter duration than many other income funds, this Fund is not intended to operate like a money market fund.

Each of the following risks, which are described in alphabetical order and not in order of any presumed importance, can significantly affect the Fund’s performance. The relative importance of, or potential exposure as a result of, each of these risks will vary based on market and other investment-specific considerations.

Call Risk. Upon the issuer’s desire to call a security, or under other circumstances where a security is called, including when interest rates are low and issuers opt to repay the obligation underlying a “callable security” early, the Fund may have to reinvest the proceeds in an investment offering a lower yield and may not benefit from any increase in value that might otherwise result from declining interest rates.

Collateralized Debt Obligations Risk. CDOs, which include collateralized loan obligations (CLOs), issue classes or “tranches” of securities that vary in risk and yield and may experience substantial losses due to interest rate fluctuations, actual defaults, collateral defaults, disappearance of subordinate tranches, market anticipation of defaults, and investor aversion to CDO securities as a class. The risks of investing in CDOs depend largely on the quality and type of the underlying debt, which may include loans, bonds and mortgages, and the tranche of the CDO in which the Fund invests. In addition, CDOs that obtain their exposure through derivative instruments entail the additional risks associated with such instruments. CDOs can be difficult to value, may at times be illiquid, may be highly leveraged (which could make them highly volatile), and may produce unexpected investment results due to their complex structure. In addition, CDOs involve many of the same risks of investing in debt securities and asset-backed securities including, but not limited to, interest rate risk, credit risk, liquidity risk, and valuation risk.

Credit Risk. Credit risk is the risk that issuers, guarantors, or insurers may fail, or become less able or unwilling, to pay interest and/or principal when due. Changes in the actual or perceived creditworthiness of an issuer, or a downgrade or default affecting any of the Fund’s securities could affect the Fund’s performance. Generally, the longer the maturity and the lower the credit quality of a security, the more sensitive it is to credit risk.

Currency Risk. Currency risk is the risk that foreign currencies will decline in value relative to the U.S. dollar. To the extent that the Fund invests in securities or other instruments denominated in or indexed to foreign currencies, changes in currency exchange rates could adversely impact investment gains or add to investment losses. Currency exchange rates may fluctuate significantly over short periods of time and can be affected unpredictably by various factors, including investor perception and changes in interest rates; intervention, or failure to intervene, by U.S. or foreign governments, central banks, or supranational entities; or by currency controls or political developments in the U.S. or abroad.

Derivatives Risk. Use of derivatives is a highly specialized activity that can involve investment techniques and risks different from, and in some respects greater than, those associated with investing in more traditional investments, such as stocks and bonds. Derivatives can be highly complex and highly volatile and may perform in unanticipated ways. Derivatives can create leverage, and the Fund could lose more than the amount it invests; some derivatives can have the potential for unlimited losses. Derivatives may at times be highly illiquid, and the Fund may not be able to close out or sell a derivative at a particular time or at an anticipated price. Derivatives can be difficult to value and valuation may be more difficult in times of market turmoil. The value of a derivative instrument depends largely on (and is derived from) the value of the reference instrument underlying the derivative. There may be imperfect correlation between the behavior of a derivative and that of the reference instrument underlying the derivative. An abrupt change in the price of a reference instrument could render a derivative worthless. Derivatives may involve risks different from, and possibly greater than, the risks associated with investing directly in the reference instrument. Suitable derivatives may not be available in all circumstances, and there can be no assurance that the Fund will use derivatives to reduce exposure to other risks when that might have been beneficial. Derivatives involve counterparty risk, which is the risk that the other party to the derivative will fail to make required payments or otherwise comply with the terms of the derivative. That risk is generally thought to be greater with over-the-counter (OTC) derivatives than with derivatives that are exchange traded or centrally cleared. When the Fund uses derivatives, it will likely be required to provide margin or collateral and/or segregate cash or other liquid assets; these practices are intended to satisfy contractual undertakings and regulatory requirements and will not prevent the Fund from incurring losses on derivatives. The need to provide margin or collateral and/or segregate assets could limit the Fund's ability to pursue other opportunities as they arise. Ongoing changes to regulation of the derivatives markets and actual and

potential changes in the regulation of funds using derivative instruments could limit the Fund’s ability to pursue its investment strategies. New regulation of derivatives may make them more costly, or may otherwise adversely affect their liquidity, value or performance.

Additional risks associated with certain types of derivatives are discussed below:

Forward Contracts. There are no limitations on daily price movements of forward contracts. Changes in foreign exchange regulations by governmental authorities might limit the trading of forward contracts on currencies.

Futures. Futures contracts are subject to the risk that an exchange may impose price fluctuation limits, which may make it difficult or impossible for a fund to close out a position when desired. In the absence of such limits, the liquidity of the futures market depends on participants entering into offsetting transactions rather than taking or making delivery. To the extent a Fund enters into futures contracts requiring physical delivery (e.g., certain commodities contracts), the inability of the Fund to take or make physical delivery can negatively impact performance.

Swaps. The risk of loss with respect to swaps generally is limited to the net amount of payments that the Fund is contractually obligated to make or, in the case of the other party to a swap defaulting, the net amount of payments that the Fund is contractually entitled to receive. If the Fund sells a credit default swap, however, the risk of loss may be the entire notional amount of the swap.

Some swaps are now executed through an organized exchange or regulated facility and cleared through a regulated clearing organization. The absence of an organized exchange or market for swap transactions may result in difficulties in trading and valuation, especially in the event of market disruptions. The use of an organized exchange or market for swap transactions is expected to result in swaps being easier to trade or value, but this may not always be the case.

Foreign and Emerging Market Risk. Foreign securities, including those issued by foreign governments, involve risks in addition to those associated with comparable U.S. securities. Additional risks include exposure to less developed or less efficient trading markets; social, political, diplomatic, or economic instability; trade barriers and other protectionist trade policies (including those of the U.S.); significant government involvement in an economy and/or market structure; fluctuations in foreign currencies or currency redenomination; potential for default on sovereign debt; nationalization or expropriation of assets; settlement, custodial or other operational risks; higher transaction costs; confiscatory withholding or other taxes; and less stringent auditing, corporate disclosure, governance, and legal standards. As a result, foreign securities may fluctuate more widely in price, and may also be less liquid, than comparable U.S. securities. Regardless of where a company is organized or its stock is traded, its performance may be affected significantly by events in regions from which it derives its profits or in which it conducts significant operations.

Investing in emerging market countries involves risks in addition to and greater than those generally associated with investing in more developed foreign countries. The governments of emerging market countries may be more unstable and more likely to impose capital controls, nationalize a company or industry, place restrictions on foreign ownership and on withdrawing sale proceeds of securities from the country, intervene in the financial markets, and/or impose burdensome taxes that could adversely affect security prices. To the extent a foreign security is denominated in U.S. dollars, there is also the risk that a foreign government will not let U.S. dollar-denominated assets leave the country. In addition, the economies of emerging market countries may be dependent on relatively few industries that are more susceptible to local and global changes. Emerging market countries may also have less developed legal and accounting systems, and their legal systems may deal with issuer bankruptcies and defaults differently than U.S. law would. Securities markets in emerging market countries are also relatively small and have substantially lower trading volumes. Securities of issuers in emerging market countries may be more volatile and less liquid than securities of issuers in foreign countries with more developed economies or markets and the situation may require that the Fund fair value its holdings in those countries.

Securities of issuers traded on foreign exchanges may be suspended, either by the issuers themselves, by an exchange, or by governmental authorities. The likelihood of such suspensions may be higher for securities of issuers in emerging or less-developed market countries than in countries with more developed markets. Trading suspensions may be applied from time to time to the securities of individual issuers for reasons specific to that issuer, or may be applied broadly by exchanges or governmental authorities in response to market events. Suspensions may last for significant periods of time, during which trading in the securities and in instruments that reference the securities, such as derivative instruments, may be halted. In the event that the Fund holds material positions in such suspended securities or instruments, the Fund’s ability to liquidate its positions or provide liquidity to investors may be compromised and the Fund could incur significant losses.

High Portfolio Turnover. The Fund may engage in active and frequent trading and may have a high portfolio turnover rate, which may increase the Fund’s transaction costs and may adversely affect the Fund’s performance.

Interest Rate Risk.The Fund’s yield and share price will fluctuate in response to changes in interest rates. In general, the value of investments with interest rate risk, such as debt securities, will move in the direction opposite to movements in interest rates. If interest rates rise, the value of such securities may decline. 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 Fund’s debt securities to interest rate risk will increase with any increase in the duration of those securities.

Issuer-Specific Risk. An individual security may be more volatile, and may perform differently, than the market as a whole.

Leverage Risk. Leverage amplifies changes in the Fund’s net asset value and may make the Fund more volatile. Derivatives and when-issued and forward-settling securities may create leverage and can result in losses to the Fund that exceed the amount originally invested and may accelerate the rate of losses. There can be no assurance that the Fund’s use of any leverage will be successful. The Fund’s investment exposure can exceed its net assets, sometimes by a significant amount.

Liquidity Risk. From time to time, the trading market for a particular investment in which the Fund invests, or a particular type of instrument in which the Fund is invested, may become less liquid or even illiquid. Illiquid investments frequently can be more difficult to purchase or sell at an advantageous price or time, and there is a greater risk that the investments may not be sold for the price at which the Fund is carrying them. Certain investments that were liquid when the Fund purchased them may become illiquid, sometimes abruptly. Additionally, market closures due to holidays or other factors may render a security or group of securities (e.g., securities tied to a particular country or geographic region) illiquid for a period of time. An inability to sell a portfolio position can adversely affect the Fund’s value or prevent the Fund from being able to take advantage of other investment opportunities. Market prices for such securities or other investments may be volatile. During periods of substantial market volatility, an investment or even an entire market segment may become illiquid, sometimes abruptly, which can adversely affect the Fund’s ability to limit losses.

Unexpected episodes of illiquidity, including due to market or political factors, instrument or issuer-specific factors and/or unanticipated outflows, may limit the Fund’s ability to pay redemption proceeds within the allowable time period. To meet redemption requests during periods of illiquidity, the Fund may be forced to sell securities at an unfavorable time and/or under unfavorable conditions.

Lower-Rated Debt Securities Risk. Lower-rated debt securities (commonly known as “junk bonds”) and unrated debt securities determined to be of comparable quality involve greater risks than investment grade debt securities. Such securities may fluctuate more widely in price and yield and may fall in price during times when the economy is weak or is expected to become weak. These securities also may require a greater degree of judgment to establish a price and may be difficult to sell at the time and price the Fund desires. Lower-rated debt securities are considered by the major rating agencies to be predominantly speculative with respect to the issuer’s continuing ability to pay principal and interest and carry a greater risk that the issuer of such securities will default in the timely payment of principal and interest. Issuers of securities that are in default or have defaulted may fail to resume principal or interest payments, in which case the Fund may lose its entire investment. The creditworthiness of issuers of these securities may be more complex to analyze than that of issuers of investment grade debt securities, and the overreliance on credit ratings may present additional risks.

Market Volatility Risk. Markets may be volatile and values of individual securities and other investments, including those of a particular type, may decline significantly in response to adverse issuer, political, regulatory, market, economic or other developments that may cause broad changes in market value, public perceptions concerning these developments, and adverse investor sentiment or publicity. Geopolitical and other risks, including environmental and public health risks may add to instability in world economies and markets generally. Changes in value may be temporary or may last for extended periods. If the Fund sells a portfolio position before it reaches its market peak, it may miss out on opportunities for better performance.

Mortgage- and Asset-Backed Securities Risk. The value of mortgage- and asset-backed securities, including collateralized mortgage instruments, will be influenced by the factors affecting the housing market or the assets underlying the securities. These securities tend to be more sensitive to changes in interest rates than other types of debt securities. In addition, investments in mortgage- and asset-backed securities may be subject to prepayment risk and extension risk, call risk, credit risk, valuation risk, and illiquid investment risk, sometimes to a higher degree than various other types of debt securities. These securities are also subject to the risk of default on the underlying mortgages or assets, particularly during periods of market downturn, and an unexpectedly high rate of defaults on the underlying assets will adversely affect the security’s value.

Other Investment Company Risk. To the extent the Fund invests in other investment companies, including money market funds and exchange-traded funds (ETFs), its performance will be affected by the performance of those other investment

companies. Investments in other investment companies are subject to the risks of the other investment companies’ investments, as well as to the other investment companies’ expenses.

An ETF may trade in the secondary market at a price below the value of its underlying portfolio and may not be liquid. An actively managed ETF’s performance will reflect its adviser’s ability to make investment decisions that are suited to achieving the ETF’s investment objectives. A passively managed ETF may not replicate the performance of the index it intends to track.

Prepayment and Extension Risk. The Fund’s performance could be affected if borrowers pay back principal on certain debt securities, such as mortgage- or asset-backed securities, before (prepayment) or after (extension) the market anticipates such payments, shortening or lengthening their duration. Due to a decline in interest rates or an excess in cash flow into the issuer, a debt security might be called or otherwise converted, prepaid or redeemed before maturity. As a result of prepayment, the Fund 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. Conversely, rising market interest rates generally result in slower payoffs or extension, which effectively increases the duration of certain debt securities, heightening interest rate risk and increasing the magnitude of any resulting price declines.

Private Placements and Other Restricted Securities Risk. Private placements and other restricted securities, including securities for which Fund management has material non-public information, are securities that are subject to legal and/or contractual restrictions on their sales. These securities may not be sold to the public unless certain conditions are met, which may include registration under the applicable securities laws. As a result of the absence of a public trading market, the prices of these securities may be more difficult to determine than publicly traded securities and these securities may involve heightened risk as compared to investments in securities of publicly traded companies. Private placements and other restricted securities may be illiquid, and it frequently can be difficult to sell them at a time when it may otherwise be desirable to do so or the Fund may be able to sell them only at prices that are less than what the Fund regards as their fair market value. Transaction costs may be higher for these securities. In addition, the Fund may get only limited information about the issuer of a private placement or other restricted security.

Recent Market Conditions. National economies are substantially interconnected, as are global financial markets, which creates the possibility that conditions in one country or region might adversely impact issuers in a different country or region. Some countries, including the U.S., have in recent years adopted more protectionist trade policies. The rise in protectionist trade policies, changes to some major international trade agreements and the potential for changes to others, could affect the economies of many nations in ways that cannot necessarily be foreseen at the present time. Markets have been sensitive to the outlook for resolving the U.S.-China “trade war,” a trend that may continue in the future. Russia’s assertion of its influence in its surrounding region, including potential actions in Ukraine, increases the likelihood of additional sanctions by the U.S. and other countries, which may cause volatility in the markets.

High public debt in the U.S. and other countries creates ongoing systemic and market risks and policymaking uncertainty, and there may be a further increase in public debt due to the economic effects of the COVID-19 pandemic and ensuing economic relief and public health measures. Governments and central banks have moved to limit the potential negative economic effects of the COVID-19 pandemic with interventions that are unprecedented in size and scope and may continue to do so, but the ultimate impact of these efforts is uncertain. Governments’ efforts to limit potential negative economic effects of the pandemic may be altered, delayed, or eliminated at inopportune times for political, policy or other reasons. Interest rates have been unusually low in recent years in the U.S. and abroad. It is difficult to predict the impact on various markets of a significant rate increase or other significant policy changes, perhaps in response to indications of increasing inflation. Over the longer term, rising interest rates may present a greater risk than has historically been the case due to the current period of relatively low rates and the effect of government fiscal and monetary policy initiatives and potential market reaction to those initiatives or their alteration or cessation.

The impact of the pandemic has negatively affected and may continue to affect the economies of many nations, individual companies and the global securities and commodities markets, including their liquidity, in ways that cannot necessarily be foreseen at the present time. The pandemic has accelerated trends toward working remotely and shopping on-line, which may negatively affect the value of office and commercial real estate and companies that have been slow to transition to an on-line business model, and has disrupted the supply chains that many businesses depend on. The travel, hospitality and public transit industries may suffer long-term negative effects from the pandemic and resulting changes to public behavior.

Over the past several years, the U.S. has moved away from tighter industry regulation, a trend that appears to be changing. Increased regulation may impose added costs on the Fund and its service providers for monitoring and compliance, and affect the businesses of various portfolio companies, in ways that cannot necessarily be foreseen at the present time.

Climate Change. There is widespread concern about the potential effects of global climate change on property and security values. A rise in sea levels, a change in weather patterns, including an increase in powerful storms and large wildfires, and/or a climate-driven increase in flooding could cause properties to lose value or become unmarketable altogether. Unlike previous declines in the real estate market, properties in affected zones may not ever recover their value. The U.S. administration appears concerned about the climate change problem and is focusing regulatory and public works projects around those concerns. Regulatory changes tied to concerns about climate change could adversely affect the value of certain land and the viability of certain industries.

Losses related to climate change could adversely affect corporate issuers and mortgage lenders, the value of mortgage-backed securities, the bonds of municipalities that depend on tax or other revenues and tourist dollars generated by affected properties, and insurers of the property and/or of corporate, municipal or mortgage-backed securities. Since property and security values are driven largely by buyers’ perceptions, it is difficult to know the time period over which these market effects might unfold.

LIBOR Transition. Certain financial contracts around the world specify rates that are based on the London Interbank Offered Rate (LIBOR), which is produced daily by averaging the rates for inter-bank lending reported by a number of banks. As previously announced by the United Kingdom’s Financial Conduct Authority, most maturities and currencies of LIBOR were phased out at the end of 2021, with the remaining ones to be phased out on June 30, 2023. There are risks that the financial services industry will not have a suitable substitute in place by that time and that there will not be time to perform the substantial work necessary to revise the many existing contracts that rely on LIBOR. The transition process, or a failure of the industry to transition properly, might lead to increased volatility and illiquidity in markets that currently rely on LIBOR. It also could lead to a reduction in the value of some LIBOR-based investments and reduce the effectiveness of new hedges placed against existing LIBOR-based instruments. New York has passed legislation to ease the transition from LIBOR and federal LIBOR transition relief legislation has been proposed, but there is no assurance whether or when such legislation will be enacted or if it will adequately address all issues or be subject to litigation.

Redemption Risk. The Fund may experience periods of large or frequent redemptions that could cause the Fund to sell assets at inopportune times, which could have a negative impact on the Fund’s overall liquidity, or at a loss or depressed value. Redemption risk is greater to the extent that one or more investors or intermediaries control a large percentage of investments in the Fund and the risk is heightened during periods of declining or illiquid markets. Large redemptions could hurt the Fund’s performance, increase transaction costs, and create adverse tax consequences. A general rise in interest rates has 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; such a move, 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.

Sector Risk. From time to time, based on market or economic conditions, the Fund may have significant positions in one or more sectors of the market. To the extent the Fund 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 or regulatory events.

Sovereign Debt Risk. Sovereign debt securities are subject to the risk that a governmental entity may delay or refuse to pay interest or principal on its sovereign debt, due, for example, to cash flow problems, insufficient foreign currency reserves, political considerations, the size of the governmental entity’s debt position in relation to the economy, its policy toward international lenders or the failure to put in place economic reforms required by multilateral agencies. If a governmental entity defaults, it may ask for more time in which to pay or for further loans. There may be no legal process for collecting sovereign debt that a government does not pay nor are there bankruptcy proceedings through which all or part of the sovereign debt that a governmental entity has not repaid may be collected. Sovereign debt risk is increased for emerging market issuers.

U.S. Government Securities Risk. Although the Fund may hold securities that carry U.S. government guarantees, these guarantees do not extend to shares of the Fund itself and do not guarantee the market prices of the securities. Furthermore, not all securities issued by the U.S. government and its agencies and instrumentalities are backed by the full faith and credit of the U.S. Treasury. Securities not backed by the full faith and credit of the U.S. Treasury carry at least some risk of non-payment or default.

Variable and Floating Rate Instruments Risk. The market prices of instruments with variable and floating interest rates are generally less sensitive to interest rate changes than are the market prices of instruments with fixed interest rates. Variable and

floating rate instruments may decline in value if market interest rates or interest rates paid by such instruments do not move as expected. Certain types of floating rate instruments, such as interests in bank loans, may be subject to greater liquidity risk than other debt securities.

When-Issued and Forward-Settling Securities Risk. When-issued and forward-settling securities can have a leverage-like effect on the Fund, which can increase fluctuations in the Fund’s share price; may cause the Fund to liquidate positions when it may not be advantageous to do so, in order to satisfy its purchase obligations; and are subject to the risk that the security will not be issued or that a counterparty will fail to complete the sale or purchase of the security, in which case the Fund may lose the opportunity to purchase or sell the security at the agreed upon price.

A summary of the Fund’s additional principal investment risks is as follows:

Risk of Increase in Expenses. A decline in the Fund’s average net assets during the current fiscal year due to market volatility or other factors could cause the Fund’s expenses for the current fiscal year to be higher than the expense information presented in “Fees and Expenses.”

Operational and Cybersecurity Risk. The Fund and its service providers, and your ability to transact with the Fund, may be negatively impacted due to operational matters arising from, among other problems, human errors, systems and technology disruptions or failures, or cybersecurity incidents. Cybersecurity incidents may allow an unauthorized party to gain access to fund assets, customer data, or proprietary information, or cause the Fund or its service providers, as well as the securities trading venues and their service providers, to suffer data corruption or lose operational functionality. Cybersecurity incidents can result from deliberate attacks or unintentional events. It is not possible for the Manager or the other Fund service providers to identify all of the cybersecurity or other operational risks that may affect the Fund or to develop processes and controls to completely eliminate or mitigate their occurrence or effects. Most issuers in which the Fund invests are heavily dependent on computers for data storage and operations, and require ready access to the internet to conduct their business. Thus, cybersecurity incidents could also affect issuers of securities in which the Fund invests, leading to significant loss of value.

Risk Management. Risk is an essential part of investing. No risk management program can eliminate the Fund’s exposure to adverse events; at best, it may only reduce the possibility that the Fund will be affected by such events, and especially those risks that are not intrinsic to the Fund’s investment program. The Fund could experience losses if judgments about risk prove to be incorrect.

Valuation Risk. The Fund may not be able to sell an investment at the price at which the Fund has valued the investment. Such differences could be significant, particularly for illiquid securities and securities that trade in relatively thin markets and/or markets that experience extreme volatility. If market or other conditions make it difficult to value some investments, SEC rules and applicable accounting protocols may require the Fund to value these investments using more subjective methods, known as fair value methodologies. Using fair value methodologies to price investments may result in a value that is different from an investment’s most recent price and from the prices used by other mutual funds to calculate their NAVs. The Fund’s ability to value its investments in an accurate and timely manner may be impacted by technological issues and/or errors by third party service providers, such as pricing services or accounting agents.

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The Fund is a mutual fund, not a bank deposit, and is not guaranteed or insured by the Federal Deposit Insurance Corporation or any other government agency.

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The following bar chart and table provide an indication of the risks of investing in the Fund. The bar chart shows how the Fund’s performance has varied from year to year. The table below the bar chart shows what the returns would equal if you averaged out actual performance over various lengths of time and compares the returns with the returns of a broad-based market index. The index, which is described in “Description of Index” in the prospectus, has characteristics relevant to the Fund's investment strategy. The performance information does not reflect variable contract or qualified plan fees and expenses. If such fees and expenses were reflected, returns would be less than those shown. Please refer to the prospectus for your variable contract or your qualified plan documentation for information on their separate fees and expenses.

Returns would have been lower if Neuberger Berman Investment Advisers LLC had not reimbursed certain expenses and/or waived a portion of the investment management fees during certain of the periods shown.

Past performance is not a prediction of future results. Visit www.nb.com or call 800-877-9700 for updated performance information.

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800-877-9700

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Past performance is not a prediction of future results.

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Best quarter: Q2 '20, 5.25%

Worst quarter: Q1 '20, -4.54%

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