This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. There are no shareholder fees (fees paid directly from your investment) when you buy and sell shares of the Fund. Future expenses may be greater or less.

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 rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in 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 17% of the average value of its portfolio.

Portfolio Turnover, Rate

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17.00%

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 assumes that you invest $10,000 in the Fund for the time periods indicated whether or not you redeem 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 may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

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Principal investment strategies of the Fund

Strategy Narrative [Text Block]

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To achieve the Fund’s investment objectives, EULAV Asset Management (the “Adviser”) invests substantially all of the Fund’s net assets in common stocks. Under normal circumstances, the Adviser invests at least 80% of the Fund’s assets in common stocks and other equity securities of mid-sized companies (the “80% Policy”). The Fund considers companies to be mid-sized if they have market capitalizations between $2 billion and $18 billion at the time of purchase. The 80% policy can be changed without shareholder approval upon at least 60 days, prior written notice. Under normal circumstances, the Adviser expects that the Fund’s portfolio will generally consist of positions in 30 to 50 companies. While the Fund is actively managed by the Adviser, the Adviser relies primarily on the rankings of companies by the Value Line Timeliness^TM Ranking System (the “Ranking System”) in selecting securities for purchase or sale. The Ranking System is a proprietary quantitative system that compares an estimate of the probable market performance of each stock within a universe during the next six to twelve months to that of all stocks within that universe and ranks stocks on a scale of 1 (highest) to 5 (lowest). The universe followed by the Ranking System consists of stocks of approximately 1,700 companies accounting for approximately 95% of the market capitalization of all stocks traded on the U.S. securities exchanges. All the stocks followed by the Ranking System are listed on U.S. stock exchanges or traded in the U.S. over-the-counter markets. The Fund’s investments principally, as measured by the number and total value of purchases, are selected from common stocks ranked 1, 2 or 3 by the Ranking System at the time of purchase. Apart from the diversification requirements of the Investment Company Act of 1940 (the “1940 Act”) applicable to diversified funds (which generally means that it will not invest more than 5% of its total assets in the stocks of any one company), the Fund is not subject to any limit on the percentage of its assets that may be invested in any particular stock.

The Adviser may sell securities for a variety of reasons, such as to secure gains, limit losses or redeploy assets into more promising opportunities.

As described above, the Adviser relies primarily on the rankings of companies by the Ranking System in selecting stocks for the Fund, but has discretion, including whether and which ranked stocks to include within the Fund’s portfolio, whether and when to buy or sell stocks based upon changes in their rankings, and the frequency and timing of rebalancing the Fund’s portfolio. The Adviser will determine the percentage of the Fund’s assets invested in each stock based on the stock’s relative attractiveness taking into account the potential risk and reward of each investment.

Strategy Portfolio Concentration [Text]

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Risk [Heading]

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Principal risks of investing in the Fund

Risk Narrative [Text Block]

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Investing in any mutual fund involves risk, including the risk that you may receive little or no return on your investment, and that you may lose money. Therefore, before you invest in the Fund you should carefully evaluate the risks.

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Mid-Sized Company Risk. The equity securities of mid-sized companies typically involve greater investment risks than larger, more established companies because they often have greater price volatility, lower trading volume, and less liquidity, especially over the short term. As compared to larger companies, mid-sized companies may have limited management experience or depth, limited ability to generate or borrow capital needed for growth, and limited products or services, or operate in markets that have not yet been established. Accordingly, mid-sized company securities tend to be more sensitive to changing economic, market and industry conditions. Mid-sized companies also may fall out of favor relative to larger companies in certain market cycles, causing the Fund to incur losses or underperform.

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Market Risk. The chief risk that you assume when investing in the Fund is market risk, which is the possibility that the securities in a certain market will decline in value because of factors such as economic conditions. Market risk may affect a single issuer, an industry, a sector of the economy, or the market as a whole.

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Equity Securities Risk. Equity securities represent ownership in a corporation and their prices fluctuate for a number of reasons including issuer-specific events, market perceptions and general movements in the equity markets. The resulting fluctuation in the price of equity securities may take the form of a drastic movement or a sustained trend. If an issuer is liquidated or declares bankruptcy, the claims of owners of bonds will take precedence over the claims of owners of common stocks. Historically, the prices of equity securities have fluctuated more than bond prices.

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Ranking System Risk. The Adviser’s use of the results of the Ranking Systems in managing the Fund involves the risk that the Ranking Systems may not have the predictive qualities anticipated by the Adviser or that over certain periods of time the price of securities not covered by the Ranking Systems, or lower ranked securities, may appreciate to a greater extent than those securities in the Fund’s portfolio.

■	Active Management Risk. Because the Fund is actively managed, its investment return depends on the ability of the Adviser to manage its portfolio successfully. There can be no guarantee that the Adviser’s investment strategies will produce the desired results.

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Cyber Security Risk. As the use of technology has become more prevalent in the course of business, the Fund has become more susceptible to operational, financial and information security risks resulting from cyber-attacks and/or technological malfunctions. Successful cyber-attacks and/or technological malfunctions affecting the Fund or its service providers can result in, among other things, financial losses to the Fund and its shareholders, the inability to process transactions with shareholders or other parties and the release of private shareholder information or confidential Fund information. While measures have been developed which are designed to reduce the risks associated with cyber security, there are inherent limitations in such measures and there is no guarantee those measures will be effective, particularly since the Fund does not directly control the cyber security measures of its service providers, financial intermediaries and companies in which it invests or with which it does business.

An investment in the Fund is not a complete investment program and you should consider it just one part of your total investment program. An investment in the Fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency. For a more complete discussion of risk, please turn to page 38.

Risk Lose Money [Text]

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Investing in any mutual fund involves risk, including the risk that you may receive little or no return on your investment, and that you may lose money.

Risk Not Insured Depository Institution [Text]

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Bar Chart and Performance Table [Heading]

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Fund performance

Performance Narrative [Text Block]

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This bar chart and table can help you evaluate the potential risks of investing in the Fund. The bar chart below shows how returns for the Fund’s Investor Class shares have varied over the past ten calendar years, and the table below shows the average annual total returns (before and after taxes) of these shares for one, five, and ten years. These returns are compared to the performance of the S&P 500^® Index, which is a broad based market index. The Fund’s past performance (before and after taxes) is not necessarily an indication of how it will perform in the future. No performance is shown for Institutional Class shares because this class is not yet being offered. Updated performance information is available at: www.vlfunds.com.

Performance Information Illustrates Variability of Returns [Text]

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Performance Availability Website Address [Text]

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www.vlfunds.com

Performance Past Does Not Indicate Future [Text]

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The Fund’s past performance (before and after taxes) is not necessarily an indication of how it will perform in the future.

Bar Chart [Heading]

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Total returns (before taxes) as of 12/31 each year (%)

Bar Chart Closing [Text Block]

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Best Quarter: Q3 2010 +12.70

Worst Quarter: Q4 2008 –27.78

After-tax returns for Investor Class shares included in the table below are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”). No performance is shown for Institutional Class shares because this class is not yet being offered.

Performance Table Heading

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Average Annual Total Returns for Periods Ended December 31, 2015

Performance Table Uses Highest Federal Rate

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Performance Table Not Relevant to Tax Deferred

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Actual after-tax returns depend on an investor’s tax situation and may differ from those shown, and after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements, such as 401(k) plans or individual retirement accounts (“IRAs”).

Value Line Mid Cap Focused Fund, Inc. | Investor Class

Risk/Return:

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Trading Symbol

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VLIFX

Management Fees

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0.69%

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Distribution and Service (12b-1) Fees

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