The Total Annual Fund Operating Expenses do not correlate to the ratio of expenses to average net assets appearing in the Financial Highlights tables, which tables reflect only the operating expenses of the fund and do not include acquired fund fees and expenses.

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 and then 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 Narrative [Text Block]

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The fund utilizes a rules based investment process and may invest in securities representing the approximately 130 sub-sectors of the primary sectors of the S&P 500® Index and/or cash equivalents (high-quality short-term securities). Allocations to each sub-sector are based on quantitative models.

The fund has the flexibility to invest in any combination of the sub-sectors and high-quality short-term securities, or 100% in high-quality short-term securities. A relative strength momentum model is utilized to rank each sub-sector of the equity market. The fund will allocate to those top sub-sectors that the model determines are more likely to outperform the broad market. A market risk indicator model is also used to determine whether the market is in a lower or higher level of risk based on price trends in the overall market. When the market is determined to be in a higher level of risk, a defensive cash equivalent position may be built by allocating from those sub-sectors of the market that are not exhibiting absolute positive momentum, up to 100% of fund assets. During periods when the model indicates that the market is in a higher level of risk, an exchange-traded fund (“ETF”) representing the S&P500® Index may be sold short in an amount equal to the total cash allocation up to a limit of 25% of net assets.

The adviser is responsible for final model specification, portfolio construction, model monitoring, and governance. The subadviser, Euclid Advisors, LLC monitors the fund’s allocations to the underlying securities and is responsible for rebalancing assets to maintain target allocations among the underlying sub-sectors, while taking into account any other factors the subadviser may deem relevant, such as cash flow and/or timing considerations.

Risk Narrative [Text Block]

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The fund may not achieve its objective(s), and it is not intended to be a complete investment program. The value of the fund’s investments that supports your share value may decrease. If between the time you purchase shares and the time you sell shares the value of the fund’s investments decreases, you will lose money. Investment values can decrease for a number of reasons. Conditions affecting the overall economy, specific industries or companies in which the fund invests can be worse than expected, and investments may fail to perform as the subadviser expects. As a result, the value of your shares may decrease. Purchase and redemption activities by fund shareholders may impact the management of the fund and its ability to achieve its investment objective(s). The redemption by one or more large shareholders or groups of shareholders of their holdings in the fund could have an adverse impact on the remaining shareholders in the fund including by accelerating the realization of capital gains and increasing the fund's transaction costs. The principal risks of investing in the fund are:

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Equity Securities Risk. The risk that events negatively affecting issuers, industries or financial markets in which the fund invests, will impact the value of the stocks held by the fund and thus, the value of the fund’s shares over short or extended periods. Investments in a particular style or in small or medium-sized companies may enhance that risk.

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Market Volatility Risk. The risk that the value of the securities in which the fund invests may go up or down in response to the prospects of individual companies and/or general economic conditions. Price changes may be temporary or may last for extended periods.

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Portfolio Turnover Risk. The risk that the fund’s principal investment strategies will result in a consistently high portfolio turnover rate. See the Portfolio Turnover section above for more information about the impact that portfolio turnover can have on your investment.

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Quantitative Model Risk. The risk that investments selected using quantitative models may perform differently from the market as a whole or from their expected performance. There can be no assurance that use of a quantitative model will enable the fund to achieve positive returns or outperform the market.

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Sector Focused Investing Risk. The risk that events negatively affecting a particular industry or market sector in which the fund focuses its investments will cause the value of the fund’s shares to decrease, perhaps significantly. To the extent that the fund invests a significant portion of its portfolio in ETFs representing one or more of the primary sectors of the S&P 500® Index (such as consumer discretionary, energy, healthcare) or in an ETF representing U.S. Treasuries, the fund is more vulnerable to conditions that negatively affect such sectors as compared to a fund that is not significantly invested in such sectors.

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Short Sales Risk. The risk that a fund may experience a loss if the price of a borrowed security increases between the date of a short sale and the date on which the fund replaces the security.

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U.S. Government Securities Risk. The risk that U.S. Government securities in the fund’s portfolio will be subject to price fluctuations, or that an agency or instrumentality will default on an obligation not backed by the full faith and credit of the United States.

Bar Chart and Performance Table [Heading]

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Performance Information

Performance Information Illustrates Variability of Returns [Text]

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The bar chart shows changes in the fund’s performance from year to year over a 10-year period. The table shows how the fund’s average annual returns compare to those of a broad-based securities market index and a more narrowly-based benchmark.

Performance Availability Website Address [Text]

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virtus.com

Bar Chart [Heading]

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Calendar year total returns for Class A Shares (includes returns of a predecessor fund)

Bar Chart Does Not Reflect Sales Loads [Text]

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Returns do not reflect sales charges and would be lower if they did.

Performance Table Heading

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Average Annual Total Returns (for the periods ended 12/31/15; includes returns of a predecessor fund)

Performance Table Uses Highest Federal Rate

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After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table One Class of after Tax Shown [Text]

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After-tax returns are shown only for Class A Shares; after-tax returns for other classes will vary.

Performance Table Narrative

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Returns reflect deduction of maximum sales charges and full redemption at end of periods shown.