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 53% of the average value of its portfolio.

Portfolio Turnover, Rate

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53.00%

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 invests primarily in a diversified portfolio of equity securities of small and medium capitalization U.S. companies, generally representing 60 to 125 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 this Fund, small and medium capitalization companies are those that, at the time of investment, fall within the capitalization range between the smallest company in the Russell 2500^™ Value Index (as of March 31, 2022, and as provided by the Sub‑Adviser, this amount was $32.83 million) and the market capitalization of the largest company in the Russell 2500^™ Value Index (as of March 31, 2022, and as provided by the Sub‑Adviser, this amount was $39.27 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. The Fund’s investments in small capitalization companies may include micro-capitalization companies.

The Fund invests in companies that are determined by the Sub‑Adviser to be undervalued, using its fundamental value approach. In selecting securities for the Fund, the Sub‑Adviser uses its fundamental research to identify companies whose long-term earnings power is not reflected in the current market price of their securities. The Sub‑Adviser’s fundamental value approach to equity investing generally defines value as the relationship between a security’s current price and its intrinsic economic value, as measured by long-term earnings prospects.

To the extent that companies involved in certain industries may from time to time constitute a material portion of the universe of small and medium capitalization companies, the Fund may also invest significantly in these industries (but not more than 25% of its total assets in any one industry). 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, Industrials Sector, Information Technology Sector, Financials Sector, and Real Estate Sector, as each sector is defined by the Global Industry Classification Standard. The Fund may invest in American Depositary Receipts (“ADRs”) and non‑U.S. securities.

The Sub‑Adviser will generally sell a security when it reaches fair value on a risk-adjusted basis. Typically, growth in the size of a company’s market capitalization relative to other domestically traded companies will not cause the Sub‑Adviser to dispose of the security.

The Fund may invest in securities issued by non‑U.S. companies and enter into forward commitments.

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.

“Value” Investing Risk. The possibility that the Fund’s investments in securities believed by the Sub‑Adviser to be undervalued may not realize their perceived value for extended periods of time or may never realize their perceived value. The securities in which the Fund invests may respond differently to market and other developments than other types of securities, and may underperform growth stocks and/or the market as a whole, particularly if the Fund’s investment style shifts out of favor.

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.

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 Consumer

Discretionary Sector, Industrials Sector, Information Technology, Financials Sector, and Real Estate Sector. In addition to these general risks, the sectors specified are also subject to the risks described below.

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.

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.

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.

Financials Sector Risk. The Financials Sector includes companies involved in banking, thrifts and mortgage finance, specialized finance, consumer finance, asset management and custody banks, investment banking and brokerage and insurance. It also includes the Financial Exchanges & Data and Mortgage Real Estate Investment Trusts (“REITs”) sub‑industries. Certain financial sector companies serve as counterparties with which the Fund may enter into derivatives agreements or other similar contractual arrangements. Companies operating in the Financials Sector are subject to extensive government regulation, which may limit the financial commitments they can make and the interest rates and fees they can charge. Profitability is largely dependent on the availability and cost of capital funds, and can fluctuate significantly when interest rates change or due to increased competition.

Real Estate Sector Risk. The Real Estate Sector contains companies operating in real estate development and operation. It also includes companies offering real estate related services and REITs. The performance of companies operating in the Real Estate Sector has historically been cyclical and particularly sensitive to the overall economy and market changes, including declines in the value of real estate or, conversely, saturation of the real estate market, economic downturns and defaults by borrowers or tenants during such periods, increases in competition, possible lack of mortgage funds or other limits to accessing the credit or capital markets, and changes in interest rates.

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.

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.

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.

Currency Risk. The possibility that the value of the Fund’s assets may be affected favorably or unfavorably by currency exchange rates, currency exchange control regulations, and restrictions or prohibitions on the repatriation of foreign currencies.

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.

Forward Commitment Risk. The possibility that the Fund engages in when-issued, delayed delivery or forward commitment transactions (e.g., TBAs) and a counterparty fails to consummate the sale, resulting in a missed opportunity by the Fund to obtain an advantageous price or yield. Such transactions may also have the effect of leverage on the Fund and may cause the Fund to be more volatile. Additionally, these transactions may create a higher portfolio turnover rate.

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 long-term growth of capital.

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. 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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