The following table describes the fees and expenses you may pay if you buy and hold shares of the Virtus KAR Capital Growth Series. The table does not include any fees or sales charges imposed under the variable contracts for which the Series is an investment option. If they were included, your costs would be higher.

Shareholder Fees Caption [Text]

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Shareholder Fees (fees paid directly from your investment)

Operating Expenses Caption [Text]

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

Fee Waiver or Reimbursement over Assets, Date of Termination

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April 30, 2018

Portfolio Turnover [Heading]

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Portfolio Turnover

Portfolio Turnover [Text Block]

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The Series 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. These costs, which are not reflected in Annual Series Operating Expenses or in the Example, affect the Series’ performance. During the most recent fiscal year, the Series’ portfolio turnover rate was 23% of the average value of its portfolio.

Portfolio Turnover, Rate

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23.00%

Expenses Not Correlated to Ratio Due to Acquired Fund Fees [Text]

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The Total Annual Series 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 Series and do not include proxy expenses.

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 Series with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the Series 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, that the Series’ total operating expenses remain the same and that the expense reimbursement arrangement remains in place for the contractual period. The example does not reflect variable contract fees and charges, and if it did, the costs shown would be higher. 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

Strategy Narrative [Text Block]

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The Series invests in a select group of large-cap growth companies believed to be undervalued relative to their future growth potential. The investment strategy emphasizes companies the subadviser believes to have a sustainable competitive advantage, strong management and low financial risk, and to be able to grow over market cycles.

Under normal conditions, the Series invests at least 80% of its assets in equity securities of large capitalization companies. The subadviser considers large capitalization companies for this purpose to be those companies that, at the time of initial purchase, have market capitalizations within the range of the Russell 1000® Growth Index on a rolling three-year basis. The Series may also invest in small and medium capitalization companies. Generally, the Series invests in approximately 30-50 securities at any given time.

Risk [Heading]

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Principal Risks

Risk Narrative [Text Block]

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The Series may not achieve its objective(s), and it is not intended to be a complete investment program. The value of the Series' 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 Series' 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 Series 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 variable contract owners may impact the management of the Series and its ability to achieve its investment objective(s). The redemption by one or more large variable contract owners or groups of variable contract owners of their holdings in the Series could have an adverse impact on the remaining variable contract owners in the Series including by accelerating the realization of capital gains and increasing the Series' transaction costs. The principal risks of investing in the Series are:

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

> Growth Stocks Risk. The risk that the Series' investments in growth stocks will be more volatile than investments in other types of stocks, or will perform differently from the market as a whole and from other types of stocks.

> Limited Number of Investments Risk. The risk that the Series' portfolio will be more susceptible to factors adversely affecting issuers of securities in the Series' portfolio than would a fund holding a greater number of securities.

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

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 Series’ investments decreases, you will lose money.

Bar Chart and Performance Table [Heading]

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Performance

Performance Narrative [Text Block]

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The following bar chart and table provide some indication of the risks of investing in the Series. The bar chart shows changes in the Series’ performance from year to year over a 10-year period. The table shows how the Series’ average annual returns compare to those of a broad-based securities market index. The Series’ past performance is not necessarily an indication of how the Series will perform in the future. The Series’ returns in the chart and table do not reflect the deduction of any separate account or variable contract charges. The returns would have been less than those shown if such charges were deducted.

Performance Information Illustrates Variability of Returns [Text]

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Performance Availability Phone [Text]

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800-367-5877

Performance Availability Website Address [Text]

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virtus.com

Performance Past Does Not Indicate Future [Text]

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The Series’ past performance is not necessarily an indication of how the Series will perform in the future.

Bar Chart Narrative [Text Block]

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Annual Return (%)

Bar Chart Does Not Reflect Sales Loads [Text]

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The Series’ returns in the chart and table do not reflect the deduction of any separate account or variable contract charges. The returns would have been less than those shown if such charges were deducted.

Bar Chart Closing [Text Block]

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Best Quarter:

1Q/2012:

16.59%

Worst Quarter:

3Q/2011:

-20.30%

Year to date (3/31/17):

10.54%

Performance Table Heading

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Average Annual Total Returns (for the periods ended 12/31/16)

Performance Table Closing [Text Block]

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Updated performance information is available at virtus.com or by calling 800-367-5877.

Virtus KAR Capital Growth Series | Class A

Risk/Return:

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Shareholder Fees

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none

Management Fees

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0.70%

Distribution and/or Service (12b-1) Fees

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0.25%

Other Expenses

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0.22%

Total Annual Series Operating Expenses

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1.17%

^[1]

Less: Expense Reimbursement

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(0.14%)

^[2]

Total Annual Series Operating Expenses After Expense Reimbursement

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1.03%

^[1],[2]

1 Year

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$ 105

3 Years

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358

5 Years

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630

10 Years

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$ 1,408

2007

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10.75%

2008

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(40.78%)

2009

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29.93%

2010

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14.88%

2011

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(4.60%)

2012

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13.76%

2013

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29.44%

2014

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11.73%

2015

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9.26%

Annual Return 2016

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(0.86%)

Year to Date Return, Label

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Year to date

Bar Chart, Year to Date Return, Date

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Mar. 31, 2017

Bar Chart, Year to Date Return

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10.54%

Highest Quarterly Return, Label

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Best Quarter:

Highest Quarterly Return, Date

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Mar. 31, 2012

Highest Quarterly Return

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16.59%

Lowest Quarterly Return, Label

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Worst Quarter:

Lowest Quarterly Return, Date

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Sep. 30, 2011

Lowest Quarterly Return

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(20.30%)

Label

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Class A

1 Year

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(0.86%)

5 Years

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12.25%

10 Years

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5.23%

Virtus KAR Capital Growth Series | Russell 1000® Growth Index (does not reflect fees or expenses)

Risk/Return:

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Index No Deduction for Fees, Expenses, Taxes [Text]

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(does not reflect fees or expenses)

Label

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Russell 1000® Growth Index (does not reflect fees or expenses)

1 Year

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7.08%

5 Years

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14.50%

10 Years

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8.33%

[1]

[2]

The Series' investment adviser has contractually agreed to limit the Series' total annual operating expenses (excluding certain expenses, such as front-end or contingent deferred sales charges, taxes, interest, brokerage commissions, unusual or infrequently occurring expenses (such as litigation) and acquired fund fees and expenses, if any) so that such expenses do not exceed 1.03% through April 30, 2018. Following the contractual period, the adviser may discontinue this expense reimbursement arrangement at any time. Under certain conditions, the adviser may recapture operating expenses reimbursed under this arrangement for a period of three years following the time such reimbursement occurred.