This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund, but does not reflect the effect of any fees or other expenses of any variable annuity or variable life insurance product. If variable annuity or variable life contract fees were included, expenses would be higher:

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 brokerage commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover 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. The portfolio turnover rate for the Predecessor Fund for the fiscal year ended December 31, 2016 was 30%.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

30.00%

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, except as indicated, 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 and that all fee waivers or expense limits for the Fund will expire after two years. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

The Fund’s Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The Fund seeks to achieve its investment goal by investing primarily in a diversified portfolio of fixed-income and equity securities. The following table details, under normal circumstances, how the Fund generally expects to allocate its assets among equity and fixed-income, as of the date of this prospectus.

Allocations Approximate Target Allocation

Equity 60%

Fixed-Income 40%

With respect to equities, the Fund invests primarily in issuers having a market capitalization, at the time of purchase, above $5 billion. Equity securities include common stock and preferred stock. These securities may be listed on an exchange or traded over-the-counter. Up to 35% of the Fund’s equity sleeve may be invested in securities of foreign issuers through the use of ordinary shares or depositary receipts such as American Depositary Receipts (“ADRs”). The Fund may also invest in equity securities of emerging market countries.

With respect to fixed-income, the Fund will invest primarily in bonds, including mortgage-related securities, asset-backed securities, government securities (both U.S. government securities and foreign sovereign debt), and corporate debt securities. Fort Washington Investment Advisors, Inc., the Fund's sub-advisor (the "Sub-Advisor"), primarily invests in investment-grade debt securities, but may invest up to 30% of the Fund's fixed-income sleeve in non-investment-grade debt securities rated as low as B by a Nationally Recognized Statistical Rating Organization (“NRSRO”). Non-investment-grade debt securities are often referred to as “junk bonds” and are considered speculative.

The Fund may engage in frequent and active trading as part of its principal investment strategies. Additionally, in order to implement its investment strategy, the Fund may invest in mortgage dollar-roll transactions and reverse repurchase agreements, and in derivatives, including forwards, futures contracts, interest rate and credit default swap agreements, and options. Mortgage “dollar rolls” are transactions in which mortgage-backed securities are sold for delivery in the current month and the seller simultaneously contracts to repurchase substantially similar securities on a specified future date. These investments may be used to gain or hedge market exposure, to adjust the Fund’s duration, to manage interest rate risk, and for any other purposes consistent with the Fund’s investment strategies and limitations.

The Sub-Advisor, subject to approval by the Fund’s Advisor, may change the Fund’s target allocation to each asset class (or to additional asset classes) without prior approval from or notice to shareholders.

Risk [Heading]

rr_RiskHeading

The Fund’s Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

The Fund’s share price will fluctuate. You could lose money on your investment in the Fund, and the Fund could also return less than other investments. The Fund is subject to the principal risks listed below.

Asset-Backed Securities Risk: Asset-backed securities are fixed-income securities backed by other assets such as credit card, automobile or consumer loan receivables, retail installment loans, or participations in pools of leases. The values of these securities are sensitive to changes in the credit quality of the underlying collateral, the credit strength of any credit enhancement feature, changes in interest rates, and, at times, the financial condition of the issuer.

Derivatives Risk: The use of derivatives may expose the Fund to additional risks that it would not be subject to if it invested directly in the securities underlying those derivatives. Risks associated with derivatives may include the risk that the derivative does not correlate well with the security, index, or currency to which it relates, the risk that the Fund will be unable to sell or close out the derivative due to an illiquid market, the risk that the counterparty may be unwilling or unable to meet its obligations, and the risk that the derivative could expose the Fund to the risk of magnified losses resulting from leverage. These additional risks could cause the Fund to experience losses to which it would otherwise not be subject.

•

Leverage Risk: Leverage occurs when the Fund uses borrowings, derivatives, or similar instruments or techniques to gain exposure to investments in an amount that exceeds the Fund's initial investment. The use of leverage magnifies changes in the Fund’s net asset value and thus may result in increased portfolio volatility and increased risk of loss. Leverage can create an interest expense that may lower the Fund’s overall returns. There can be no guarantee that a leveraging strategy will be successful.


•	Futures Contracts Risk: The risks associated with the Fund's futures positions include liquidity and counterparty risks associated with derivative investments.

•

Options Risk: Options trading is a highly specialized activity that involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. The value of options can be highly volatile, and their use can result in loss if the Sub-Advisor is incorrect in its expectation of price fluctuations. Options, whether exchange traded or over-the-counter, may also be illiquid. The Fund will limit its investments in illiquid securities to no more than 15% of net assets.

•

Swap Agreements Risk: Swap agreements (“swaps”) are individually negotiated and structured to include exposure to a variety of different types of investments or market factors. Swaps may increase or decrease the overall volatility of the investments of the Fund and its share price. The performance of swaps may be affected by a change in the specific interest rate, currency, or other factors that determine the amounts of payments due to and from the Fund. A swap can be a form of leverage, which can magnify the Fund’s gains or losses.

Equity Securities Risk: The Fund is subject to the risk that stock prices will fall over short or extended periods of time. Individual companies may report poor results or be negatively affected by industry and/or economic trends and developments. The prices of securities issued by these companies may decline in response to such developments, which could result in a decline in the value of the Fund’s shares.


•	Large-Cap Risk: Large-cap companies may be unable to respond quickly to new competitive challenges, such as changes in technology and consumer tastes, and also may not be able to attain the high growth rate of successful smaller companies, especially during extended periods of economic expansion.

Fixed-Income Risk: The market value of the Fund’s fixed-income securities responds to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments. Generally, the Fund’s fixed-income securities will decrease in value if interest rates rise and increase in value if interest rates fall. Normally, the longer the maturity or duration of the fixed-income securities the Fund owns, the more sensitive the value of the Fund’s shares will be to changes in interest rates.


•	Credit Risk: The fixed-income securities in the Fund’s portfolio are subject to the possibility that a deterioration, whether sudden or gradual, in the financial condition of an issuer, or a deterioration in general economic conditions, could cause an issuer to fail to make timely payments of principal or interest, when due. This may cause the issuer’s securities to decline in value.

•

Distressed Securities Risk: Distressed securities are speculative and involve significant risks in addition to the risks generally applicable to non-investment grade debt securities. Distressed securities bear a substantial risk of default, and may be in default at the time of investment. The Fund will generally not receive interest payments on distressed securities, and there is a significant risk that principal will not be repaid, in full or at all. Distressed securities will likely be illiquid and may be subject to restrictions on resale.


•	Interest Rate Risk: In general, when interest rates rise, the prices of debt securities fall, and when interest rates fall, the prices of debt securities rise. The price volatility of a debt security also depends on its maturity. Longer-term securities are generally more volatile, so the longer the average maturity or duration of these securities, the greater their price risk.

•

Non-Investment-Grade Debt Securities Risk: Non-investment-grade debt securities are sometimes referred to as “junk bonds” and are considered speculative with respect to their issuers’ ability to make payments of interest and principal. There is a high risk that the Fund could suffer a loss from investments in non-investment-grade debt securities caused by the default of an issuer of such securities. Non-investment-grade debt securities may also be less liquid than investment-grade debt securities.

Foreign Securities Risk: Investing in foreign securities poses additional risks since political and economic events unique in a country or region will affect those markets and their issuers, while such events may not necessarily affect the U.S. economy or issuers located in the United States. In addition, investments in foreign securities are generally denominated in foreign currency. As a result, changes in the value of those currencies compared to the U.S. dollar may affect (positively or negatively) the value of the Fund's investments. Foreign markets may be less liquid and more volatile than U.S. markets and offer less protection to investors.


•	Depositary Receipts Risk: Foreign receipts, which include ADRs, Global Depositary Receipts, and European Depositary Receipts, are securities that evidence ownership interests in a security or a pool of securities issued by a foreign issuer. The risks of depositary receipts include many risks associated with investing directly in foreign securities.


•	Emerging Markets Risk: Emerging markets may be more likely to experience political turmoil or rapid changes in market or economic conditions than more developed countries. In addition, the financial stability of issuers (including governments) in emerging market countries may be more precarious than that of issuers in other countries.

Investment-Grade Debt Securities Risk: Investment-grade debt securities may be downgraded by a nationally recognized statistical rating organization (“NRSRO”) to below-investment-grade status, which would increase the risk of holding these securities. Investment-grade debt securities rated in the lowest rating category by a NRSRO involve a higher degree of risk than fixed-income securities with higher credit ratings.

Management Risk: In managing the Fund’s portfolio, the Advisor engages one or more sub-advisors to make investment decisions for a portion of or the entire portfolio. There is a risk that the Advisor may be unable to identify and retain sub-advisors who achieve superior investment returns relative to other similar sub-advisors.

Mortgage-Backed Securities Risk: Mortgage-backed securities are fixed-income securities representing an interest in a pool of underlying mortgage loans. Mortgage-backed securities are sensitive to changes in interest rates, but may respond to these changes differently from other fixed-income securities due to the possibility of prepayment of the underlying mortgage loans. Mortgage-backed securities may fluctuate in price based on deterioration in the value of the collateral underlying the pool of mortgage loans, which may result in the collateral being worth less than the remaining principal amount owed on the mortgages in the pool.

Mortgage Dollar Roll Risk: If the broker-dealer to whom the Fund sells the mortgage-backed security becomes insolvent, the Fund’s right to repurchase the security may be restricted. Other risks involved in entering into mortgage dollar rolls include the risk that the value of the security may change adversely over the term of the mortgage dollar roll and that the security the Fund is required to repurchase may be worth less than the security that the Fund held.

Portfolio Turnover Risk: Frequent and active trading may result in greater expenses to the Fund, which may lower the Fund’s performance and may result in the realization of substantial capital gains, including net short-term capital gains. As a result, high portfolio turnover may reduce the Fund’s returns.

U.S. Government Agencies Securities Risk: Certain U.S. government agency securities are backed by the right of the issuer to borrow from the U.S. Treasury while others are supported only by the credit of the issuer or instrumentality. While the U.S. government is able to provide financial support to U.S. government-sponsored agencies or instrumentalities, no assurance can be given that it will always do so.

As with any mutual fund, there is no guarantee that the Fund will achieve its investment goal. You can find more information about the Fund’s investments and risks under the “Investment Strategies and Risks” section of the Fund’s prospectus.

Risk Lose Money [Text]

rr_RiskLoseMoney

You could lose money on your investment in the Fund, and the Fund could also return less than other investments.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

The Fund’s Performance

Performance One Year or Less [Text]

rr_PerformanceOneYearOrLess

The Fund is a new series of the Trust and has no performance history. As a result of the Reorganization, the performance and accounting history of the Predecessor Fund will be assumed by the Fund.

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

1.800.543.0407

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

TouchstoneInvestments.com

Bar Chart [Heading]

rr_BarChartHeading

Predecessor Fund - Total Return as of December 31 (%)

Bar Chart Narrative [Text Block]

rr_BarChartNarrativeTextBlock

The Fund is a new series of the Trust and has no performance history. As a result of the Reorganization, the performance and accounting history of the Predecessor Fund will be assumed by the Fund. The performance information included herein is that of the Predecessor Fund.

The bar chart and the performance table below illustrate the risks and volatility of an investment in the Fund by showing changes in the Predecessor Fund’s performance from calendar year to calendar year and by showing how the Predecessor Fund’s average annual total returns for one year, five years, and ten years compare with the S&P 500® Index and the Bloomberg Barclays US Aggregate Bond Index. Past performance of the Predecessor Fund (before and after taxes) does not necessarily indicate how the Fund will perform in the future. More recent performance for the Fund is available at no cost by visiting TouchstoneInvestments.com or by calling 1.800.543.0407.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter: Second Quarter, 2009 11.76% Worst Quarter: Fourth Quarter, 2008 (13.35)%

The Predecessor Fund’s calendar year-to-date total return as of September 30, 2017 was 9.60%.

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total ReturnsFor the periods ended December 31, 2016

TOUCHSTONE VARIABLE SERIES TRUST | Touchstone Balanced Fund | Touchstone Balanced Fund Class

Prospectus:

rr_ProspectusTable

Management Fees (as a percentage of Assets)

rr_ManagementFeesOverAssets

0.55%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses (as a percentage of Assets):

rr_OtherExpensesOverAssets

0.52%

^[1]

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.02%

^[1]

Expenses (as a percentage of Assets)

rr_ExpensesOverAssets

1.09%

Fee Waiver or Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.22%)

^[2]

Net Expenses (as a percentage of Assets)

rr_NetExpensesOverAssets

0.87%

^[2]

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

$ 89

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

302

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

557

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,288

Annual Return 2007

rr_AnnualReturn2007

8.44%

Annual Return 2008

rr_AnnualReturn2008

(23.95%)

Annual Return 2009

rr_AnnualReturn2009

21.47%

Annual Return 2010

rr_AnnualReturn2010

12.19%

Annual Return 2011

rr_AnnualReturn2011

4.05%

Annual Return 2012

rr_AnnualReturn2012

11.44%

Annual Return 2013

rr_AnnualReturn2013

18.88%

Annual Return 2014

rr_AnnualReturn2014

7.81%

Annual Return 2015

rr_AnnualReturn2015

0.03%

Annual Return 2016

rr_AnnualReturn2016

7.42%

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

9.60%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

11.76%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(13.35%)

Label

rr_AverageAnnualReturnLabel

Predecessor Fund

1 Year

rr_AverageAnnualReturnYear01

7.42%

5 Years

rr_AverageAnnualReturnYear05

8.95%

10 Years

rr_AverageAnnualReturnYear10

6.02%

TOUCHSTONE VARIABLE SERIES TRUST | Touchstone Balanced Fund | Touchstone Balanced Fund Class | S&P 500 Index

Prospectus:

rr_ProspectusTable

Label

rr_AverageAnnualReturnLabel

S&P 500® Index(1) (reflects no deduction for fees, expenses or taxes)

1 Year

rr_AverageAnnualReturnYear01

11.96%

^[3]

5 Years

rr_AverageAnnualReturnYear05

14.66%

^[3]

10 Years

rr_AverageAnnualReturnYear10

6.95%

^[3]

TOUCHSTONE VARIABLE SERIES TRUST | Touchstone Balanced Fund | Touchstone Balanced Fund Class | Bloomberg Barclays U.S. Aggregate Bond Index

Prospectus:

rr_ProspectusTable

Label

rr_AverageAnnualReturnLabel

Bloomberg Barclays US Aggregate Bond Index(2) (reflects no deduction for taxes or certain expenses)

1 Year

rr_AverageAnnualReturnYear01

2.65%

^[4]

5 Years

rr_AverageAnnualReturnYear05

2.23%

^[4]

10 Years

rr_AverageAnnualReturnYear10

4.34%

^[4]

TOUCHSTONE VARIABLE SERIES TRUST | Touchstone Bond Fund

Prospectus:

rr_ProspectusTable

Risk/Return [Heading]

rr_RiskReturnHeading

TOUCHSTONE BOND FUND SUMMARY

Objective [Heading]

rr_ObjectiveHeading

The Fund's Investment Goals

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The Touchstone Bond Fund (the "Fund") seeks to provide as high a level of current income as is consistent with the preservation of capital. Capital appreciation is a secondary goal.

Expense [Heading]

rr_ExpenseHeading

The Fund's Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

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 brokerage 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 fund operating expenses or in the example, affect the Fund's performance. The portfolio turnover rate for the Predecessor Fund for the fiscal year ended December 31, 2016 was 197%.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

197.00%

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 does not include expenses incurred from investing through a variable annuity or a variable life insurance product. If the example included these expenses, the figures shown would be higher. 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 and that all fee waivers or expense limits for the Fund will expire after two years. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

rr_StrategyHeading

The Fund's Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

Under normal conditions, the Fund invests at least 80% of its assets (including borrowing for investment purposes) in bonds. This is a non-fundamental investment policy that the Fund can change upon 60 days prior notice to shareholders. Bonds include mortgage-related securities, asset-backed securities, government securities, and corporate debt securities.

In deciding what securities to buy and sell for the Fund, the Fund's sub-advisor, Fort Washington Investment Advisors, Inc. ("Fort Washington" or "Sub-Advisor"), analyzes the overall investment opportunities and risks in different sectors of the debt securities markets by focusing on maximizing total return while reducing volatility of the Fund's portfolio.

In building the Fund's portfolio, the Sub-Advisor primarily invests in investment-grade debt securities, but may invest up to 30% of its total assets in non-investment-grade debt securities rated as low as B by a Nationally Recognized Statistical Rating Organization ("NRSRO"). Non-investment-grade debt securities are often referred to as "junk bonds" and are considered speculative. The Fund may also invest up to 20% of its total assets in foreign-issued debt denominated in either the U.S. dollar or a foreign currency. Foreign-issued debt may include debt securities of emerging market countries.

Additionally, in order to implement its investment strategy the Fund may invest in mortgage dollar-roll transactions and reverse repurchase agreements, and in derivatives including forwards and futures contracts, interest rate and credit default swap agreements, and options. These investments may be used for both gaining and hedging market exposure, to adjust the Fund's duration, to manage interest rate risk, and for any other purposes consistent with its investment strategies and limitations.

The Fund may engage in frequent and active trading as part of its principal investment strategy.

Risk [Heading]

rr_RiskHeading

The Fund's Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

The Fund's share price will fluctuate. You could lose money on your investment in the Fund and the Fund could also return less than other investments. The Fund is subject to the principal risks summarized below.


•	Forward Currency Exchange Contract Risk: Forward foreign currency exchange contracts may reduce the risk of loss from a change in value of a currency, but they also limit any potential gains, do not protect against fluctuations in the value of the underlying position and are subject to the risk that the counterparty to the transaction will not meet its obligations.


•	Futures Contracts Risk: The risks associated with futures include the potential inability to terminate or sell a position, the lack of a liquid secondary market for the Fund's position and the risk that the counterparty to the transaction will not meet its obligations.


•	Leverage Risk: Leverage occurs when the Fund increases its assets available for investment using borrowings, derivatives, or similar instruments or techniques. The use of leverage may make any change in the Fund's net asset value even greater and thus result in increased volatility of returns.


•	Options Risk: Options trading is a highly specialized activity that involves investment techniques and risks different from those associated with ordinary portfolio securities transactions. The value of options can be highly volatile, and their use can result in loss if the Sub-Advisor is incorrect in its expectation of price fluctuations.

•

Swap Agreement Risk: The Fund bears the risk of loss of the amount expected to be received under a swap agreement in the event of the default or bankruptcy of a counterparty. Swap agreements also may be considered to be illiquid. The Fund could lose money by investing in an interest rate swap if interest rates change adversely. Credit default swaps involve special risks because they may be difficult to value, are highly susceptible to liquidity and credit risk, and generally pay a purchaser only in the event of an actual default by the issuer of the underlying obligation (as opposed to a credit downgrade or other indication of financial difficulty).

Fixed-Income Risk: The market value of the Fund's fixed-income securities responds to economic developments, particularly interest rate changes, as well as to perceptions about the creditworthiness of individual issuers, including governments. Generally, the Fund's fixed-income securities will decrease in value if interest rates rise and increase in value if interest rates fall. Normally, the longer the maturity or duration of the fixed-income securities the Fund owns, the more sensitive the value of the Fund's shares will be to changes in interest rates.

•

Asset-Backed Securities Risk: Asset-backed securities are fixed-income securities backed by other assets such as credit card, automobile or consumer loan receivables, retail installment loans, or participations in pools of leases. There could be inadequate collateral or no collateral for asset-backed securities. The values of these securities are sensitive to changes in the credit quality of the underlying collateral, the credit strength of the credit enhancement, changes in interest rates and, at times, the financial condition of the issuer. Some asset-backed securities are subject to prepayments that can change the securities' effective durations.


•	Credit Risk: The fixed-income securities in the Fund's portfolio are subject to the possibility that a deterioration, whether sudden or gradual, in the financial condition of an issuer, or a deterioration in general economic conditions, could cause an issuer to fail to make timely payments of principal or interest, when due. This may cause the issuer's securities to decline in value.

•

Interest Rate Risk: As interest rates rise, the value of fixed-income securities the Fund owns will likely decrease. The price of debt securities is generally linked to prevailing market interest rates. In general, when interest rates rise, the prices of debt securities fall, and when interest rates fall, the prices of debt securities rise. The price volatility of a debt security also depends on its maturity. Longer-term securities are generally more volatile, so the longer the average maturity or duration of these securities, the greater their price risk.

•

Investment-Grade Debt Securities Risk: Investment-grade debt securities may be downgraded by a NRSRO to below investment-grade status (also known as "junk bond" status), which would increase the risk of holding these securities, or a rating may become stale in that it fails to reflect changes to an issuer's financial condition. Investment-grade debt securities rated in the lowest rating category by a NRSRO involve a higher degree of risk than fixed-income securities in the higher-rating categories.

•


•	Emerging Markets Risk: Emerging markets may be more likely to experience political turmoil or rapid changes in market or economic conditions than more developed countries. In addition, the financial stability of issuers (including governments) in emerging market countries may be more precarious than in other countries.


•	Sovereign Debt Risk: The actions of foreign governments concerning their respective economies could have an important effect on their ability or willingness to service their sovereign debt. Such actions could have significant effects on market conditions and on the prices of securities and instruments held by the Fund, including the securities and instruments of foreign private issuers.

Management Risk: In managing the Fund's portfolio, the Advisor may engage one or more sub-advisors to make investment decisions on the portfolio or a portion thereof. There is a risk that the Advisor may be unable to identify and retain sub-advisors who achieve superior investment returns relative to other similar sub-advisors.

Portfolio Turnover Risk: Frequent and active trading may result in greater expenses to the Fund, which may lower the Fund’s performance and may result in the realization of substantial capital gains. As a result, high portfolio turnover may reduce the Fund’s returns.

As with any mutual fund, there is no guarantee that the Fund will achieve its investment goal. You can find more information about the Fund's investments and risks under the "Principal Investment Strategies and Risks" section of the Fund's prospectus.

Risk Lose Money [Text]

rr_RiskLoseMoney

You could lose money on your investment in the Fund and the Fund could also return less than other investments.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

The Fund's Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The bar chart and the performance table below illustrate the risks and volatility of an investment in the Fund by showing changes in the Predecessor Fund’s performance from calendar year to calendar year and by showing how the Predecessor Fund’s average annual total returns for one year, five years, and ten years compare with the Bloomberg Barclays US Aggregate Bond Index. Past performance of the Predecessor Fund (before and after taxes) does not necessarily indicate how the Fund will perform in the future. More recent performance for the Fund is available at no cost by visiting TouchstoneInvestments.com or by calling 1.800.543.0407.

Performance One Year or Less [Text]

rr_PerformanceOneYearOrLess

The Fund is a new series of the Trust and has no performance history. As a result of the Reorganization, the performance and accounting history of the Predecessor Fund will be assumed by the Fund.

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

1.800.543.0407

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

TouchstoneInvestments.com

Bar Chart [Heading]

rr_BarChartHeading

Predecessor Fund - Total Return as of December 31 (%)

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter: Second Quarter, 2009 5.93% Worst Quarter: Fourth Quarter, 2013 (2.78)%

The Predecessor Fund’s calendar year-to-date total return as of September 30, 2017 was 3.13%.

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the periods ended December 31, 2016

Label

rr_AverageAnnualReturnLabel

Predecessor Fund

1 Year

rr_AverageAnnualReturnYear01

0.81%

5 Years

rr_AverageAnnualReturnYear05

1.91%

10 Years

rr_AverageAnnualReturnYear10

4.50%

TOUCHSTONE VARIABLE SERIES TRUST | Touchstone Bond Fund | Bloomberg Barclays U.S. Aggregate Bond Index

Prospectus:

rr_ProspectusTable

Label

rr_AverageAnnualReturnLabel

Bloomberg Barclays U.S. Aggregate Bond Index (reflects no deductions for fees, expenses or taxes)

1 Year

rr_AverageAnnualReturnYear01

2.65%

5 Years

rr_AverageAnnualReturnYear05

2.23%

10 Years

rr_AverageAnnualReturnYear10

4.34%

TOUCHSTONE VARIABLE SERIES TRUST | Touchstone Bond Fund | Touchstone Bond Fund Class

Prospectus:

rr_ProspectusTable

Management Fees (as a percentage of Assets)

rr_ManagementFeesOverAssets

0.40%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses (as a percentage of Assets):

rr_OtherExpensesOverAssets

0.43%

^[5]

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.03%

^[5]

Expenses (as a percentage of Assets)

rr_ExpensesOverAssets

0.86%

Fee Waiver or Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.16%)

^[6]

Net Expenses (as a percentage of Assets)

rr_NetExpensesOverAssets

0.70%

^[6]

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

$ 72

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

242

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

445

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 1,030

Annual Return 2007

rr_AnnualReturn2007

7.05%

Annual Return 2008

rr_AnnualReturn2008

3.40%

Annual Return 2009

rr_AnnualReturn2009

11.08%

Annual Return 2010

rr_AnnualReturn2010

7.33%

Annual Return 2011

rr_AnnualReturn2011

7.04%

Annual Return 2012

rr_AnnualReturn2012

6.53%

Annual Return 2013

rr_AnnualReturn2013

(0.33%)

Annual Return 2014

rr_AnnualReturn2014

4.01%

Annual Return 2015

rr_AnnualReturn2015

(1.29%)

Annual Return 2016

rr_AnnualReturn2016

0.81%

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

3.13%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

5.93%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2013

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(2.78%)

TOUCHSTONE VARIABLE SERIES TRUST | Touchstone Common Stock Fund

Prospectus:

rr_ProspectusTable

Risk/Return [Heading]

rr_RiskReturnHeading

TOUCHSTONE COMMON STOCK FUND SUMMARY

Objective [Heading]

rr_ObjectiveHeading

The Fund’s Investment Goal

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The Touchstone Common Stock Fund (the “Fund”) seeks to provide investors with capital appreciation.

Expense [Heading]

rr_ExpenseHeading

The Fund’s Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

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 brokerage commissions, when it buys and sells securities (i.e., “turns over” its portfolio). A higher portfolio turnover 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 total annual fund operating expenses or in the example, affect the Fund’s performance. The portfolio turnover rate for the Predecessor Fund for the fiscal year ended December 31, 2016 was 6%.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

6.00%

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, except as indicated, 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

The Fund’s Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The Fund invests, under normal market conditions, at least 80% of its assets in large capitalization equity securities. The Fund invests primarily in issuers having a market capitalization, at the time of purchase, above $5 billion. The Fund’s 80% policy is a non-fundamental investment policy that can be changed by the Fund upon 60 days’ prior notice to shareholders. Equity securities include common stock and preferred stock. These securities may be listed on an exchange or traded over-the-counter.

In selecting securities for the Fund, the Fund’s sub-advisor, Fort Washington Investment Advisors, Inc. (“Fort Washington” or the “Sub-Advisor”), seeks to invest in companies that:


•	Are trading below its estimate of the companies’ intrinsic value; and


•	Have a sustainable competitive advantage or a high barrier to entry in place. The barrier(s) to entry can be created through a cost advantage, economies of scale, high customer loyalty, or a government barrier (e.g., license or subsidy). Fort Washington believes that the strongest barrier to entry is the combination of economies of scale and higher customer loyalty.

The Fund will generally hold 25 to 40 companies, with residual cash and equivalents expected to represent less than 10% of the Fund’s net assets. The Fund may, at times, hold fewer securities and a higher percentage of cash and equivalents when, among other reasons, Fort Washington cannot find a sufficient number of securities that meets its purchase requirements. Although the Fund may invest in any economic sector, at times it may emphasize one or more particular sectors.

The Fund may invest up to 35% of its assets in securities of foreign issuers through the use of ordinary shares or depositary receipts such as American Depositary Receipts (“ADRs”). The Fund may also invest in securities of emerging market countries.

The Fund will generally sell a security if it reaches Fort Washington’s estimate of fair value, if a more attractive investment opportunity is available, or if a structural change has taken place and Fort Washington cannot reliably estimate the impact of the change on the business fundamentals.

The Fund is non-diversified and may invest a significant percentage of its assets in the securities of a single company.

Risk [Heading]

rr_RiskHeading

The Fund’s Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock


•	Large-Cap Risk: Large-cap companies may be unable to respond quickly to new competitive challenges, such as changes in technology and consumer tastes, and also may not be able to attain the high growth rate of successful smaller companies, especially during extended periods of economic expansion.


•	Depositary Receipts Risk: Foreign receipts, which include ADRs, GDRs, and European Depositary Receipts, are securities that evidence ownership interests in a security or a pool of securities issued by a foreign issuer. The risks of depositary receipts include many risks associated with investing directly in foreign securities.


•	Emerging Markets Risk: Emerging markets may be more likely to experience political turmoil or rapid changes in market or economic conditions than more developed countries. In addition, the financial stability of issuers (including governments) in emerging market countries may be more precarious than that of issuers in other countries.

Non-Diversification Risk: The Fund is non-diversified, which means that it may invest a greater percentage of its assets than a diversified mutual fund in the securities of a limited number of issuers. The use of a non-diversified investment strategy may increase the volatility of the Fund’s investment performance, as the Fund may be more susceptible to risks associated with a single economic, political, or regulatory event than a diversified fund.

Sector Focus Risk: The Fund may invest a high percentage of its assets in specific sectors of the market in order to achieve a potentially greater investment return. As a result, the Fund may be more susceptible to economic, political, and regulatory developments in a particular sector of the market, positive or negative than a fund that does not invest a high percentage of its assets in specific sectors.

Risk Lose Money [Text]

rr_RiskLoseMoney

You could lose money on your investment in the Fund, and the Fund could also return less than other investments.

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

The Fund is non-diversified, which means that it may invest a greater percentage of its assets than a diversified mutual fund in the securities of a limited number of issuers. The use of a non-diversified investment strategy may increase the volatility of the Fund’s investment performance, as the Fund may be more susceptible to risks associated with a single economic, political, or regulatory event than a diversified fund.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

The Fund’s Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The Fund is a new series of the Trust and has no performance history. As a result of the Reorganization, the performance and accounting history of the Predecessor Fund will be assumed by the Fund. Performance information included herein is that of the Predecessor Fund.

The bar chart and the performance table below illustrate the risks and volatility of an investment in the Fund by showing changes in the Predecessor Fund’s performance from calendar year to calendar year and by showing how the Predecessor Fund’s average annual total returns for one year, five years, and ten years compare with the S&P 500® Index. Past performance of the Predecessor Fund (before and after taxes) does not necessarily indicate how the Fund will perform in the future. More recent performance for the Fund is available at no cost by visiting TouchstoneInvestments.com or by calling 1.800.543.0407.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

Performance Availability Phone [Text]

rr_PerformanceAvailabilityPhone

1.800.543.0407

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

TouchstoneInvestments.com

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

Past performance of the Predecessor Fund (before and after taxes) does not necessarily indicate how the Fund will perform in the future.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter: Second Quarter, 2009 17.21% Worst Quarter: Fourth Quarter, 2008 (20.36)%

The Predecessor Fund’s calendar year-to-date total return as of September 30, 2017 was 15.02%.

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total ReturnsFor the Periods Ended December 31, 2016

Label

rr_AverageAnnualReturnLabel

Predecessor Fund

1 Year

rr_AverageAnnualReturnYear01

11.26%

5 Years

rr_AverageAnnualReturnYear05

13.27%

10 Years

rr_AverageAnnualReturnYear10

7.59%

TOUCHSTONE VARIABLE SERIES TRUST | Touchstone Common Stock Fund | S&P 500 Index

Prospectus:

rr_ProspectusTable

Label

rr_AverageAnnualReturnLabel

S&P 500® Index(1) (reflects no deduction for fees, expenses or taxes)

1 Year

rr_AverageAnnualReturnYear01

11.96%

5 Years

rr_AverageAnnualReturnYear05

14.66%

10 Years

rr_AverageAnnualReturnYear10

6.95%

TOUCHSTONE VARIABLE SERIES TRUST | Touchstone Common Stock Fund | Touchstone Common Stock Fund Class

Prospectus:

rr_ProspectusTable

Management Fees (as a percentage of Assets)

rr_ManagementFeesOverAssets

0.50%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses (as a percentage of Assets):

rr_OtherExpensesOverAssets

0.22%

^[7]

Expenses (as a percentage of Assets)

rr_ExpensesOverAssets

0.72%

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

$ 74

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

230

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

401

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 894

Annual Return 2007

rr_AnnualReturn2007

10.21%

Annual Return 2008

rr_AnnualReturn2008

(33.04%)

Annual Return 2009

rr_AnnualReturn2009

27.75%

Annual Return 2010

rr_AnnualReturn2010

15.80%

Annual Return 2011

rr_AnnualReturn2011

2.10%

Annual Return 2012

rr_AnnualReturn2012

15.10%

Annual Return 2013

rr_AnnualReturn2013

31.73%

Annual Return 2014

rr_AnnualReturn2014

10.34%

Annual Return 2015

rr_AnnualReturn2015

0.19%

Annual Return 2016

rr_AnnualReturn2016

11.26%

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

15.02%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.21%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(20.36%)

TOUCHSTONE VARIABLE SERIES TRUST | Touchstone Small Company Fund

Prospectus:

rr_ProspectusTable

Risk/Return [Heading]

rr_RiskReturnHeading

TOUCHSTONE SMALL COMPANY FUND SUMMARY

Objective [Heading]

rr_ObjectiveHeading

The Fund’s Investment Goal

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The Touchstone Small Company Fund (the “Fund”) seeks to provide investors with growth of capital.

Expense [Heading]

rr_ExpenseHeading

The Fund’s Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

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 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. The portfolio turnover rate for the Predecessor Fund for the fiscal year ended December 31, 2016 was 68%.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

68.00%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example.

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

Strategy [Heading]

rr_StrategyHeading

The Fund’s Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The Fund normally invests at least 80% of its assets in small-capitalization companies. This is a non–fundamental investment policy that can be changed by the Fund upon 60 days' prior notice to shareholders. For this purpose, small capitalization companies are companies that have, at the time of purchase, market capitalizations of less than $4 billion. For these purposes the market cap is determined at the time of purchase. The Fund seeks to invest primarily in common stocks of small companies that Fort Washington Investment Advisors, Inc., the Fund's sub-advisor ("Fort Washington" or the "Sub–Advisor"), believes are high quality, have superior business models, solid management teams, sustainable growth potential and are attractively valued. The Fund may invest without limitation in foreign securities, although only where the securities are trading in the U.S. or Canada and only where trading is denominated in U.S. or Canadian dollars.

Up to 25% of the Fund's assets may be invested in securities within a single industry. Although the Fund may invest in any economic sector, at times it may emphasize one or more particular sectors. At times the Fund may have less than 80% of its investments in companies with a market cap of less than $4 billion due to market appreciation.

The Fund typically sells a security if the portfolio manager believes it is overvalued, if the original investment premise is no longer true, if the holding size exceeds the portfolio manager's company or sector weighting guidelines and/or to take advantage of a more attractive investment opportunity. The Fund may also sell a partial position in a security in order to manage the size of the position. A security may also be sold to meet redemptions.

Risk [Heading]

rr_RiskHeading

The Fund’s Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

Small-Cap Risk: Stocks of smaller companies may be subject to more abrupt or erratic market movements than stocks of larger, more established companies. Small companies may have limited product lines or financial resources, and may be dependent upon a small or inexperienced management group.

Risk Lose Money [Text]

rr_RiskLoseMoney

You could lose money on your investment in the Fund, and the Fund could also return less than other investments.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

The Fund’s Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The Fund is a new series of Touchstone Variable Series Trust (the "Trust") and has no performance history. It is expected that on or about October 27, 2017, the Predecessor Fund will be reorganized into the Fund. As a result of the Reorganization, the performance and accounting history of the Predecessor Fund will be assumed by the Fund. Performance information included herein is that of the Predecessor Fund.

The bar chart and the performance table below illustrate the risks and volatility of an investment in the Fund by showing changes in the Predecessor Fund’s performance from calendar year to calendar year and by showing how the Predecessor Fund’s average annual total returns for one year, five years, and ten years compare with the Russell 2000® Index. Past performance of the Predecessor Fund (before and after taxes) does not necessarily indicate how the Fund will perform in the future. More recent performance for the Fund is available at no cost by visiting TouchstoneInvestments.com or by calling 1.800.543.0407.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

Past performance of the Predecessor Fund (before and after taxes) does not necessarily indicate how the Fund will perform in the future.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Best Quarter: Third Quarter, 2009 16.27% Worst Quarter: Fourth Quarter, 2008 (24.27)%

The Predecessor Fund’s calendar year-to-date total return for Class A shares as of September 30, 2017 was 12.08%.

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total ReturnsFor the Periods Ended December 31, 2016

TOUCHSTONE VARIABLE SERIES TRUST | Touchstone Small Company Fund | Touchstone Small Company Fund Class

Prospectus:

rr_ProspectusTable

Management Fees (as a percentage of Assets)

rr_ManagementFeesOverAssets

0.50%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses (as a percentage of Assets):

rr_OtherExpensesOverAssets

0.29%

^[8]

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.01%

^[8]

Expenses (as a percentage of Assets)

rr_ExpensesOverAssets

0.80%

Fee Waiver or Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

(0.03%)

^[9]

Net Expenses (as a percentage of Assets)

rr_NetExpensesOverAssets

0.77%

^[9]

Expense Example, No Redemption, 1 Year

rr_ExpenseExampleNoRedemptionYear01

$ 79

Expense Example, No Redemption, 3 Years

rr_ExpenseExampleNoRedemptionYear03

249

Expense Example, No Redemption, 5 Years

rr_ExpenseExampleNoRedemptionYear05

438

Expense Example, No Redemption, 10 Years

rr_ExpenseExampleNoRedemptionYear10

$ 984

Annual Return 2007

rr_AnnualReturn2007

8.60%

Annual Return 2008

rr_AnnualReturn2008

(32.29%)

Annual Return 2009

rr_AnnualReturn2009

27.15%

Annual Return 2010

rr_AnnualReturn2010

23.74%

Annual Return 2011

rr_AnnualReturn2011

3.02%

Annual Return 2012

rr_AnnualReturn2012

11.44%

Annual Return 2013

rr_AnnualReturn2013

34.72%

Annual Return 2014

rr_AnnualReturn2014

6.68%

Annual Return 2015

rr_AnnualReturn2015

(1.34%)

Annual Return 2016

rr_AnnualReturn2016

20.23%

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2017

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

12.08%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Best Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

16.27%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Worst Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(24.27%)

Label

rr_AverageAnnualReturnLabel

Predecessor Fund

1 Year

rr_AverageAnnualReturnYear01

20.23%

5 Years

rr_AverageAnnualReturnYear05

13.70%

10 Years

rr_AverageAnnualReturnYear10

8.52%

TOUCHSTONE VARIABLE SERIES TRUST | Touchstone Small Company Fund | Touchstone Small Company Fund Class | Russell 2000® Value Index

Prospectus:

rr_ProspectusTable

Label

rr_AverageAnnualReturnLabel

Russell 2000® Index(1) (reflects no deduction for fees, expenses or taxes)

1 Year

rr_AverageAnnualReturnYear01

21.31%

^[10]

5 Years

rr_AverageAnnualReturnYear05

14.46%

^[10]

10 Years

rr_AverageAnnualReturnYear10

7.07%

^[10]

[1]	The Fund is newly formed and will commence operations following the completion of the reorganization of the Sentinel Variable Products Balanced Fund (the "Predecessor Fund"), a series of Sentinel Variable Products Trust, into the Fund, which is expected to occur on or about October 27, 2017 (the "Reorganization"). Other Expenses and Acquired Fund Fees and Expenses are estimated based on fees and expenses incurred by other funds within the Touchstone fund complex during the most recent fiscal year.
[2]	Touchstone Advisors, Inc. (the "Advisor" or "Touchstone Advisors") and Touchstone Variable Series Trust (the “Trust”) have entered into a contractual expense limitation agreement whereby Touchstone Advisors will waive a portion of its fees or reimburse certain Fund expenses (excluding dividend and interest expenses relating to short sales; interest; taxes; brokerage commissions and other transaction costs; portfolio transaction and investment related expenses; other expenditures which are capitalized in accordance with U.S. generally accepted accounting principles; the cost of “Acquired Fund Fees and Expenses,” if any; and other extraordinary expenses not incurred in the ordinary course of business) in order to limit annual Fund operating expenses to 0.85% of its average daily net assets. This contractual expense limitation will remain in effect for at least two years following the closing of the Reorganization. The terms of the contractual expense limitation agreement provide that Touchstone Advisors is entitled to recoup, subject to approval by the Board, such amounts waived or reimbursed for a period of up to three years from the date of reimbursement or waiver. The Fund will make repayments to Touchstone Advisors only if such repayment does not cause the Fund’s expense ratio (after the repayment is taken into account) to exceed both (a) the expense limitation in place when such amounts were waived and (b) the Fund’s current expense limitation.
[3]	The S&P 500® Index consists of approximately 500 widely held U.S. equity securities chosen for market size, liquidity, and industry group representation.
[4]	The Bloomberg Barclays US Aggregate Bond Index measures the U.S. investment grade fixed-rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities.
[5]	The Fund is newly formed and will commence operations following the completion of the reorganization of the Sentinel Variable Products Bond Fund (the "Predecessor Fund"), a series of Sentinel Variable Products Trust, into the Fund, which is expected to occur on or about October 27, 2017 (the "Reorganization"). Other Expenses and Acquired Fund Fees and Expenses are estimated based on fees and expenses incurred by other funds within the Touchstone fund complex during the most recent fiscal year.
[6]	Touchstone Advisors, Inc. (the "Advisor" or "Touchstone Advisors") and Touchstone Variable Series Trust (the “Trust”) have entered into a contractual expense limitation agreement whereby Touchstone Advisors will waive a portion of its fees or reimburse certain Fund expenses (excluding dividend and interest expenses relating to short sales; interest; taxes; brokerage commissions and other transaction costs; portfolio transaction and investment related expenses; other expenditures which are capitalized in accordance with U.S. generally accepted accounting principles; the cost of “Acquired Fund Fees and Expenses,” if any; and other extraordinary expenses not incurred in the ordinary course of business) in order to limit annual Fund operating expenses to 0.67% of its average daily net assets. This contractual expense limitation will remain in effect for at least two years following the closing of the Reorganization. The terms of the contractual expense limitation agreement provide that Touchstone Advisors is entitled to recoup, subject to approval by the Board, such amounts waived or reimbursed for a period of up to three years from the date of reimbursement or waiver. The Fund will make repayments to Touchstone Advisors only if such repayment does not cause the Fund’s expense ratio (after the repayment is taken into account) to exceed both (a) the expense limitation in place when such amounts were waived and (b) the Fund’s current expense limitation.
[7]	The Fund is newly formed and will commence operations following the completion of the reorganization of the Sentinel Variable Products Common Stock Fund (the "Predecessor Fund"), a series of Sentinel Variable Products Trust, into the Fund, which is expected to occur on or about October 27, 2017 (the "Reorganization"). Other Expenses are estimated based on fees and expenses incurred by other funds within the Touchstone fund complex during the most recent fiscal year.
[8]	The Fund is newly formed and will commence operations following the completion of the reorganization of the Sentinel Variable Products Small Company Fund (the "Predecessor Fund"), a series of Sentinel Variable Products Trust, into the Fund, which is expected to occur on or about October 27, 2017 (the "Reorganization"). Other Expenses and Acquired Fund Fees and Expenses are estimated based on fees and expenses incurred by other funds within the Touchstone fund complex during the most recent fiscal year.
[9]	Touchstone Advisors, Inc. (the "Advisor" or "Touchstone Advisors") and Touchstone Variable Series Trust (the “Trust”) have entered into a contractual expense limitation agreement whereby Touchstone Advisors will waive a portion of its fees or reimburse certain Fund expenses (excluding dividend and interest expenses relating to short sales; interest; taxes; brokerage commissions and other transaction costs; portfolio transaction and investment related expenses; other expenditures which are capitalized in accordance with U.S. generally accepted accounting principles; the cost of “Acquired Fund Fees and Expenses,” if any; and other extraordinary expenses not incurred in the ordinary course of business) in order to limit annual Fund operating expenses to 0.76% of average daily net assets. This contractual expense limitation will remain in effect for at least two years following the closing of the Reorganization. The terms of the contractual expense limitation agreement provide that Touchstone Advisors is entitled to recoup, subject to approval by the Board, such amounts waived or reimbursed for a period of up to three years from the date of reimbursement or waiver. The Fund will make repayments to Touchstone Advisors only if such repayment does not cause the Fund’s expense ratio (after the repayment is taken into account) to exceed both (a) the expense limitation in place when such amounts were waived and (b) the Fund’s current expense limitation.
[10]	The Russell 2000® Index measures the performance of 2,000 small-cap companies within the U.S. equity universe.