The tables below illustrate all fees and expenses that you may pay if you buy and hold shares of the fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in Virtus Mutual Funds. More information about these and other discounts is available from your financial advisor and under “Sales Charges” on page 215 of the fund’s prospectus and “Alternative Purchase Arrangements” on page 103 of the fund’s statement of additional information.

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 percentage 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 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 140% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

140.00%

Expenses Deferred Charges [Text Block]

rr_ExpensesDeferredChargesTextBlock

Generally, Class A Shares are not subject to any charges by the Fund when redeemed; however, a contingent deferred sales charge may be imposed on certain redemptions (i) within 18 months on exchanges from a Virtus non-money market fund into a Virtus money market fund; and (ii) on purchases on which a finder’s fee has been paid. The 18-month period begins on the last day of the month preceding the month in which the purchase was made. The deferred sales charge is imposed on Class C Shares redeemed during the first year only.

Expense Breakpoint Discounts [Text]

rr_ExpenseBreakpointDiscounts

You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in Virtus Mutual Funds.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

$ 50,000

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

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 [Heading]

rr_StrategyHeading

Investments, Risks and Performance

Principal Investment Strategies

Strategy Narrative [Text Block]

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The fund seeks to track the Premium AlphaSector® Index (ASRP), a public index published by NASDAQ. The fund may be invested in ETFs and/or securities representing the primary sectors of the S&P 500® Index and high-quality short-term securities. The primary sectors of the S&P 500® Index represented are: consumer discretionary, consumer staples, energy, financials, healthcare, industrials, materials, technology, and utilities. Allocations are based on a proprietary quantitative model that seeks to evaluate “true” underlying trends within each sector by adjusting for unwarranted price distortions and changing levels of volatility in the market. The fund has the flexibility to be invested in any combination of the sector ETFs and/or securities, a combination of sector ETFs and/or securities and high-quality short-term securities, or 100% in high-quality short- term securities. The fund may invest in a basket of securities to represent a sector if it determines that investment in the ETF for that sector is not feasible or otherwise not in the best interest of the fund. The fund may also deviate from tracking the Premium AlphaSector® Index and/or the model allocation if it is determined that tracking the Index and/or the model allocation is likely to violate applicable legal or regulatory restrictions or otherwise result in adverse consequences for the fund.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

The fund may not achieve its objective, 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. In addition, you will also be subject to the risks associated with the principal investment strategies of any ETFs in which the fund invests. The principal risks of investing in the fund are:

Correlation to Index Risk. The risk that the performance of the fund and its index may vary somewhat due to factors such as fund flows, transaction costs, sample selection, and timing differences associated with additions to and deletions from its index.

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.

Exchange-Traded Funds (ETFs) Risk. The risk that the value of an ETF will be more volatile than the underlying portfolio of securities the ETF is designed to track, or that the costs to the fund of owning shares of the ETF will exceed those the fund would incur by investing in such securities directly.

Fund of Funds Risk. The risk that the underlying funds in which the fund invests will expose the fund to negative performance and additional expenses associated with investment in such funds, and increased volatility.

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.

Model Portfolio 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.

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 fund performance.

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.

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.

Risk Lose Money [Text]

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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.

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 provide some indication of the potential risks of investing in the fund. The fund’s past performance, before and after taxes, is not necessarily an indication of how the fund will perform in the future.

The bar chart shows the fund’s performance from year to year over the life of the fund. The table shows how the fund’s average annual returns compare to those of a broad-based securities market index. Updated performance information is available at virtus.com or by calling 800-243-1574.

Performance Information Illustrates Variability of Returns [Text]

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Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

800-243-1574

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

virtus.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 the fund will perform in the future.

Bar Chart [Heading]

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Calendar year total returns for Class A Shares

Bar Chart Narrative [Text Block]

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

Annual Return (%)

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.

Bar Chart Closing [Text Block]

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Best Quarter:

Q1/2013:

10.75%

Worst Quarter:

Q3/2011:

-9.45%

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns (for the periods ended 12/31/13)

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

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 Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on the investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold fund shares in tax-deferred accounts or to shares held by non-taxable entities.

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 Explanation after Tax Higher

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In certain cases, the Return After Taxes on Distributions and Sale of Fund Shares for a period may be higher than other return figures for the same period. This will occur when a capital loss is realized upon the sale of fund shares and provides an assumed tax benefit that increases the return.

Performance Table Narrative

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

Performance Table Closing [Text Block]

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The S&P 500® Index is a free-float adjusted market capitalization-weighted index of 500 of the largest U.S. companies. The index is calculated on a total return basis with dividends reinvested. The index is unmanaged and not available for direct investment.

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. After-tax returns are shown only for Class A Shares; after-tax returns for other classes will vary. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown.

After-tax returns are not relevant to investors who hold fund shares in tax-deferred accounts or to shares held by non-taxable entities. In certain cases, the Return After Taxes on Distributions and Sale of Fund Shares for a period may be higher than other return figures for the same period. This will occur when a capital loss is realized upon the sale of fund shares and provides an assumed tax benefit that increases the return.

Virtus Premium AlphaSector Fund | Class A

Risk/Return:

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

VAPAX

Maximum Sales Charge (load) Imposed on Purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

5.75%

Maximum Deferred Sales Charge (load) (as a percentage of the lesser of purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

1.00%

^[1]

Management Fees

rr_ManagementFeesOverAssets

1.10%

Distribution and Shareholder Servicing (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.27%

Total Annual Fund Operating Expenses

rr_NetExpensesOverAssets

1.62%

1 Year

rr_ExpenseExampleYear01

730

3 Years

rr_ExpenseExampleYear03

1,057

5 Years

rr_ExpenseExampleYear05

1,406

10 Years

rr_ExpenseExampleYear10

2,386

1 Year

rr_ExpenseExampleNoRedemptionYear01

730

3 Years

rr_ExpenseExampleNoRedemptionYear03

1,057

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,406

10 Years

rr_ExpenseExampleNoRedemptionYear10

2,386

2011

rr_AnnualReturn2011

(0.21%)

2012

rr_AnnualReturn2012

10.06%

2013

rr_AnnualReturn2013

29.24%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter:

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2013

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

10.75%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter:

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(9.45%)

Label

rr_AverageAnnualReturnLabel

Return Before Taxes

1 Year

rr_AverageAnnualReturnYear01

21.81%

Since Inception

rr_AverageAnnualReturnSinceInception

15.21%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 01, 2010

Virtus Premium AlphaSector Fund | Class C

Risk/Return:

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

VAPCX

Maximum Sales Charge (load) Imposed on Purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (load) (as a percentage of the lesser of purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

1.00%

^[2]

Management Fees

rr_ManagementFeesOverAssets

1.10%

Distribution and Shareholder Servicing (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.27%

Total Annual Fund Operating Expenses

rr_NetExpensesOverAssets

2.37%

1 Year

rr_ExpenseExampleYear01

340

3 Years

rr_ExpenseExampleYear03

739

5 Years

rr_ExpenseExampleYear05

1,265

10 Years

rr_ExpenseExampleYear10

2,706

1 Year

rr_ExpenseExampleNoRedemptionYear01

240

3 Years

rr_ExpenseExampleNoRedemptionYear03

739

5 Years

rr_ExpenseExampleNoRedemptionYear05

1,265

10 Years

rr_ExpenseExampleNoRedemptionYear10

2,706

Label

rr_AverageAnnualReturnLabel

Return Before Taxes

1 Year

rr_AverageAnnualReturnYear01

28.30%

Since Inception

rr_AverageAnnualReturnSinceInception

16.30%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 01, 2010

Virtus Premium AlphaSector Fund | Class I

Risk/Return:

rr_RiskReturnAbstract

Trading Symbol

dei_TradingSymbol

VAPIX

Maximum Sales Charge (load) Imposed on Purchases (as a percentage of offering price)

rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice

none

Maximum Deferred Sales Charge (load) (as a percentage of the lesser of purchase price or redemption proceeds)

rr_MaximumDeferredSalesChargeOverOther

none

Management Fees

rr_ManagementFeesOverAssets

1.10%

Distribution and Shareholder Servicing (12b-1) fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.27%

Total Annual Fund Operating Expenses

rr_NetExpensesOverAssets

1.37%

1 Year

rr_ExpenseExampleYear01

139

3 Years

rr_ExpenseExampleYear03

434

5 Years

rr_ExpenseExampleYear05

750

10 Years

rr_ExpenseExampleYear10

1,646

1 Year

rr_ExpenseExampleNoRedemptionYear01

139

3 Years

rr_ExpenseExampleNoRedemptionYear03

434

5 Years

rr_ExpenseExampleNoRedemptionYear05

750

10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,646

Label

rr_AverageAnnualReturnLabel

Return Before Taxes

1 Year

rr_AverageAnnualReturnYear01

29.58%

Since Inception

rr_AverageAnnualReturnSinceInception

17.45%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 01, 2010

Virtus Premium AlphaSector Fund | Return After Taxes on Distributions | Class A

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions

1 Year

rr_AverageAnnualReturnYear01

20.77%

Since Inception

rr_AverageAnnualReturnSinceInception

14.83%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 01, 2010

Virtus Premium AlphaSector Fund | Return After Taxes on Distributions and Sale of Fund Shares | Class A

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

Return After Taxes on Distributions and Sale of Fund Shares

1 Year

rr_AverageAnnualReturnYear01

12.88%

Since Inception

rr_AverageAnnualReturnSinceInception

12.01%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 01, 2010

Virtus Premium AlphaSector Fund | S&P 500 ® Index (reflects no deduction for fees, expenses or taxes)

Risk/Return:

rr_RiskReturnAbstract

Label

rr_AverageAnnualReturnLabel

S&P 500® Index (reflects no deduction for fees, expenses or taxes)

1 Year

rr_AverageAnnualReturnYear01

32.39%

Since Inception

rr_AverageAnnualReturnSinceInception

20.80%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 01, 2010

[1]

Generally, Class A Shares are not subject to any charges by the Fund when redeemed; however, a contingent deferred sales charge may be imposed on certain redemptions (i) within 18 months on exchanges from a Virtus non-money market fund into a Virtus money market fund; and (ii) on purchases on which a finder's fee has been paid. The 18-month period begins on the last day of the month preceding the month in which the purchase was made.

[2]

The deferred sales charge is imposed on Class C Shares redeemed during the first year only.