This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and Example below. Additional fees and expenses will be applied at the variable contract level. Those fees and expenses are described in your variable contract prospectus. If the information below were to reflect the deduction of variable contract charges, fees and expenses would be higher.

Operating Expenses Caption [Text]

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Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Portfolio Turnover [Heading]

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Portfolio Turnover

Portfolio Turnover [Text Block]

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The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover may indicate higher transaction costs. These costs, which are not reflected in the annual fund operating expenses or in the Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 65% of the average value of its portfolio.

Portfolio Turnover, Rate

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65.00%

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 Fund with the cost of investing in other mutual funds. The example does not reflect expenses and charges which are, or may be, imposed under your variable contract. If the examples were to reflect the deduction of such charges, the costs shown would be greater. The example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem or hold all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses remain the same. Although your actual costs and returns might be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

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Principal Investment Strategy

Strategy Narrative [Text Block]

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The Fund attempts to achieve its investment objective by investing primarily in common stocks of small and medium capitalization U.S. companies. Under normal circumstances, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in securities of small and medium capitalization companies. For purposes of this policy, small and medium capitalization companies have market capitalizations that fall within the outside range of the market capitalizations of companies in the Russell 2000^® Growth Index and the Russell Midcap^® Growth Index at the time of purchase (as of March 31, 2022, and as provided by the Sub‑Adviser, this range was between $12.14 million and $61.32 billion). Because the Fund’s definition of small and medium capitalization companies is dynamic, the lower and upper limits on market capitalization will change with the markets. If the market capitalization of a company held by the Fund moves outside the range, the Fund may, but is not required to, sell the security. The Fund’s investments in small capitalization companies may include micro-capitalization companies. Although the Fund invests primarily in publicly traded U.S. securities, the Fund may invest up to 25% of its net assets in foreign securities, including securities of issuers in countries with emerging markets or economies and securities quoted in foreign

currencies. The Fund may also invest in privately held companies and companies that only recently began to trade publicly.

The Sub‑Adviser on behalf of the Fund employs a fundamental equity growth investment process that involves evaluating potential investments based on specific characteristics believed to indicate a high-quality business with sustainable growth, including strong business franchises, favorable long-term prospects, and excellent management. The Sub‑Adviser will also consider valuation of companies when determining whether to buy and/or sell securities. The Sub‑Adviser may integrate environmental, social and governance (“ESG”) factors with traditional fundamental factors as part of its fundamental research process. No one factor or consideration is determinative in the stock selection process. With respect to the valuation of any private companies held by the Fund, the Sub‑Adviser will consider a variety of factors it deems appropriate and reliable, including but not limited to, analyses of valuations of publicly traded companies in a similar line of business. The Sub‑Adviser may decide to sell a position for various reasons, including when a company’s fundamental outlook deteriorates, because of valuation and price considerations, for risk management purposes, or when a company is deemed to be misallocating capital or a company no longer fits within the Fund’s definition of a small or medium capitalization company.

The Fund may also invest in American Depositary Receipts (“ADRs”), real estate investment trusts (“REITs”), shares of other investment companies and exchange-traded funds (“ETFs”), derivatives, such as futures, options, and swap agreements, and fixed income securities, such as government, corporate and bank debt obligations.

While the Fund’s sector and industry exposure is expected to vary over time, as of February 28, 2022, the Fund had significant exposure to the Consumer Discretionary Sector, Health Care Sector, Industrials Sector, and Information Technology Sector, as each sector is defined by the Global Industry Classification Standard.

Risk [Heading]

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Principal Risks of Investing

Risk Narrative [Text Block]

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As with all mutual funds, an investor is subject to the risk that his or her investment could lose money. In addition to this risk, the Fund is subject to the principal risks described below.

Small- and Mid‑Cap Securities Risk. The possibility that the Fund’s investments in small- and mid‑cap securities may be subject to greater risk and higher volatility than are customarily associated with investing in larger more established companies. Securities issued by small- and mid‑sized companies, which can include start‑up companies, tend to be more vulnerable than larger and more established companies to adverse business and economic developments. Such companies generally have narrower product lines, more limited financial resources and more limited markets for their stock as compared with larger companies. As a result, the value of such securities also may be more volatile than the securities of larger companies, and the Fund’s portfolio may experience difficulty in purchasing or selling such securities at the desired time and price or in the desired amount.

“Growth” Investing Risk. The possibility that the Fund’s investments in securities of companies perceived to be “growth” companies may underperform when the Fund’s investment style shifts out of favor and may be more volatile than other securities because they are more sensitive to investor perceptions of the issuing company’s growth of earnings potential. Also, because growth companies usually invest a high portion of earnings in their businesses, growth stocks may lack the dividends of some value stocks that can cushion stock prices in a falling market.

Equity Securities Risk. In general, prices of equity securities are more volatile than those of fixed income securities. The prices of equity securities fluctuate, and sometimes widely fluctuate, in response to activities specific to the issuer of the security as well as factors unrelated to the fundamental condition of the issuer, including general market, economic and political conditions.

Market Risk. The possibility that the values of, and/or the income generated by, securities held by the Fund may decline, sometimes unpredictably, due to general market conditions or other factors, including those directly

involving the issuers of such securities. Security markets are volatile and may decline significantly in response to adverse issuer, regulatory, political, or economic developments. Different sectors of the market and different security types may react differently to such developments.

Management Risk. The possibility that the investment decisions, techniques, analyses or models implemented by the Fund’s Sub‑Adviser in seeking to achieve the Fund’s investment objective may not produce the returns expected, may cause the Fund’s shares to lose value or may cause the Fund to underperform relevant benchmarks or other funds with similar investment objectives.

Sector Risk. The possibility that the Fund may invest a substantial portion of its assets within one or more economic sectors or industries, which may change from time to time. At times, the Fund may have a significant portion of its assets invested in securities of companies conducting business in a broadly related group of industries within an economic sector. Companies in the same economic sector may be similarly affected by economic or market events, making the Fund more vulnerable to unfavorable developments in that economic sector, including adverse market conditions, legislative or regulatory changes, and/or increased competition affecting that sector, than funds that invest more broadly. While the Fund’s sector and industry exposure is expected to vary over time, as of February 28, 2022, the Fund had significant exposure to the Information Technology Sector, Health Care Sector, Industrials Sector, and Consumer Discretionary Sector. In addition to these general risks, the sectors specified are also subject to the risks described below.

Information Technology Sector Risk. The Information Technology Sector includes companies that offer software and information technology services, manufacturers and distributors of technology hardware and equipment such as communications equipment, cellular phones, computers and peripherals, electronic equipment and related instruments and semiconductors. The prices of the securities of companies operating in the Information Technology Sector are closely tied to market competition, increased sensitivity to short product cycles and aggressive pricing, and problems with bringing products to market.

Health Care Sector Risk. The Health Care Sector includes health care providers and services, companies that manufacture and distribute health care equipment and supplies, and health care technology companies. It also includes companies involved in the research, development, production and marketing of pharmaceuticals and biotechnology products. The prices of the securities of companies operating in the Health Care Sector are closely tied to government regulation and approval of their products and services, which can have a significant effect on the price and availability of those products and services.

Industrials Sector Risk. The Industrials Sector includes manufacturers and distributors of capital goods such as aerospace and defense, building projects, electrical equipment and machinery and companies that offer construction and engineering services. It also includes providers of commercial and professional services including printing, environmental and facilities services, office services and supplies, security and alarm services, human resource and employment services, research and consulting services. It also includes companies that provide transportation services. The prices of the securities of companies operating in the Industrials Sector may fluctuate due to the level and volatility of commodity prices, the exchange value of the dollar, import controls, worldwide competition, liability for environmental damage, depletion of resources, and mandated expenditures for safety and pollution control devices.

Consumer Discretionary Sector Risk. The manufacturing segment of the Consumer Discretionary Sector includes automotive, household durable goods, leisure equipment, and textiles and apparel. The services segment includes restaurants, hotels, and other leisure facilities, media production and services, and consumer retailing and services. The performance of companies operating in this sector has historically been closely tied to the performance of the overall economy, and also is affected by economic growth, consumer confidence, social trends, attitudes and spending. Changes in demographics, disposable income levels, and consumer tastes also can affect the demand for, and success of, consumer products and services in the marketplace. Moreover, the Consumer Discretionary Sector encompasses those businesses that tend to be the most sensitive to economic cycles.

Liquidity Risk. The possibility that the market for certain of the Fund’s investments may become illiquid under adverse or volatile market or economic conditions, making those investments difficult to sell at an advantageous

price, particularly in times of market turmoil. The market price of certain investments may fall dramatically if there is no liquid trading market for the investments. Illiquid securities may also be more difficult to value. If the Fund is forced to sell an illiquid security to fund redemptions or for other cash needs, it may be forced to sell the security at a loss.

REITs Risk. The possibility that the Fund’s investments in REITs will subject the Fund to the risks associated with the direct ownership of real estate, including fluctuations in the value of underlying properties, changes in interest rates and risks related to general or local economic conditions. REITs are dependent upon management skills and generally may not be diversified. REITs are also subject to heavy cash flow dependency, defaults by borrowers or tenants and self-liquidation.

Micro‑Cap Securities Risk. The possibility that the return on the Fund’s investments in micro‑cap companies may be less than the return on investments in stocks of larger companies or the stock market as a whole. Stock prices of micro‑cap companies may be based in substantial part on future expectations rather than current achievements and may move sharply, especially during market upturns and downturns. Micro‑cap companies are followed by relatively few securities analysts, and there tends to be less publicly available information about these companies. Micro‑cap companies are more likely to be newly formed or in the early stages of development, depend on a few key employees, and have relatively limited product lines, markets or financial resources compared to larger capitalization companies.

Foreign Investment Risk. The possibility that the Fund’s investments in foreign securities may be adversely affected by political, social, and economic conditions affecting foreign issuers or decreases in foreign currency values relative to the U.S. dollar. Investments in foreign markets may be subject to greater market volatility, decreased market liquidity, and higher transaction and custody costs. Foreign issuers also may be subject to less government and exchange regulation and there may be less reliable financial information available for such issuers and their securities.

Other Investment Company Risk. The possibility that investments by the Fund in shares of other investment companies will subject the Fund to the risks associated with those investment companies. Fund shareholders will also indirectly bear a proportionate share of any underlying investment company’s fees and expenses in addition to paying the Fund’s expenses.

Depositary Receipts Risk. The possibility that the Fund’s investments in foreign companies through depositary receipts will expose the Fund to the same risks as direct investment in securities of foreign issuers. In addition, investments in ADRs may be less liquid than the underlying shares in their primary trading market, and the value of securities underlying ADRs may change materially at times when U.S. markets are not open for trading.

Emerging Markets Risk. The possibility that the stocks of companies located in emerging markets may be more volatile, and less liquid, than the stocks of companies located in the U.S. and developed foreign markets due to political, economic, or regulatory conditions within emerging market countries. In addition, emerging market countries may experience more volatile interest and currency exchange rates, higher levels of inflation and less efficient trading and settlement systems.

Derivatives Risk. The possibility that the Fund’s use of derivatives, such as futures, options and swap agreements, may lead to losses, including those magnified by leverage, particularly when derivatives are used to enhance return rather than mitigate risk. Certain derivative instruments may be difficult to sell when the Sub‑Adviser believes it would be appropriate to do so, difficult to value if the instrument becomes illiquid, or the other party to a derivative contract may be unwilling or unable to fulfill its contractual obligations.

An investment in the Fund may be appropriate for investors who are willing to accept the risks and uncertainties of investing in common stocks in the hope of earning long-term returns.

Risk Lose Money [Text]

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As with all mutual funds, an investor is subject to the risk that his or her investment could lose money.

Bar Chart and Performance Table [Heading]

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Performance Information

Performance Narrative [Text Block]

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The bar chart and table below show the performance of the Fund both year‑by‑year and as an average over different periods of time. Performance prior to December 1, 2016 reflects the Fund’s investment performance when managed by a previous sub‑adviser pursuant to a substantially similar principal investment strategy. Since December 1, 2016, Goldman Sachs Asset Management, L.P. has been responsible for the Fund’s day‑to‑day portfolio management. Therefore, the performance and average annual total returns shown for periods prior to December 1, 2016 may have differed had Goldman Sachs Asset Management, L.P. been responsible for the day‑to‑day portfolio management during those periods. The bar chart and table demonstrate the variability of performance over time and provide an indication of the risks and volatility of an investment in the Fund by showing how the Fund’s average annual total returns for various periods compare with those of a broad-based securities market index. Past performance does not necessarily indicate how the Fund will perform in the future. This performance information does not include the impact of any charges deducted under your variable contract. If it did, returns would be lower.

Performance Information Illustrates Variability of Returns [Text]

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The bar chart and table demonstrate the variability of performance over time and provide an indication of the risks and volatility of an investment in the Fund by showing how the Fund’s average annual total returns for various periods compare with those of a broad-based securities market index.

Performance Past Does Not Indicate Future [Text]

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Past performance does not necessarily indicate how the Fund will perform in the future.

Bar Chart Does Not Reflect Sales Loads [Text]

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This performance information does not include the impact of any charges deducted under your variable contract. If it did, returns would be lower.

Bar Chart Closing [Text Block]

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