2.2.0.25truefalse010000 - Document - Risk/Return Summary {Unlabeled}falsefalsetrue1falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Putnam VT Absolute Return 500 Fund 5/1/2010 - 4/30/2011 TwelveMonthsEnded_30Apr2011_S000032103_Memberhttp://www.sec.gov/CIK0000822671duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsepvt822671_S000032103Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000032103Memberdei_DocumentInformationDocumentAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli01false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://putnam.com/role/riskreturnsummary1falsefalsefalse00Putnam VT Absolute Return 500 FundPutnam VT Absolute Return 500 Fundfalsefalsefalsefalsefalse1falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Putnam VT Absolute Return 500 Fund 5/1/2010 - 4/30/2011 TwelveMonthsEnded_30Apr2011_S000032103_Memberhttp://www.sec.gov/CIK0000822671duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsepvt822671_S000032103Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000032103Memberdei_DocumentInformationDocumentAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0OthernaNo definition available.No authoritative reference available.falsefalsePutnam VT Absolute Return 500 Fund3false0rr_RiskReturnHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fund summaries PUTNAM VT ABSOLUTE RETURN 500 FUNDfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 falsefalseRisk/Return [Heading]4false0rr_ObjectiveHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00GoalfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]5false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT Absolute Return 500 Fund seeks to earn a positive total return that exceeds the rate of inflation by 500 basis points (or 5.00%) on an annualized basis over a reasonable period of time (generally at least three years or more) regardless of market conditions.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]6false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and expensesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]7false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. The fees and expenses information does not reflect insurance-related charges or expenses borne by contract holders indirectly investing in the fund. If it did, expenses would be higher.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. 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IBfalsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherus-types:textBlockItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseShare class0rr_OperatingExpensesColumnNametruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse3falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalseOthernanafalsefalseShare class3falseRowprimaryElement*6false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00730.0073falsefalsefalsetruefalse2truetruetrue0.00730.0073falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement fees0rr_ManagementFeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00730.0073falsefalsefalsetruefalse3truetruetrue0.00730.0073falsefalsefalsetruefalseOthernanafalsefalseManagement fees4falseRowprimaryElement*7false0rr_DistributionAndService12b1FeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruetrue00&nbsp;falsefalsefalsetruefalse2truetruetrue0.00250.0025falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureDistribution [and/or Service] (12b-1) Fees" include all distribution or other expenses incurred during the most recent fiscal year under a plan adopted pursuant to rule 12b-1 [17 CFR 270.12b-1]. Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00510.0051[1]falsefalsefalsetruefalse2truetruetrue0.00510.0051[1]falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse[2]1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00510.0051falsefalsefalsetruefalse3truetruetrue0.00510.0051falsefalsefalsetruefalseOthernanafalsefalseOther expenses6falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.01240.0124falsefalsefalsetruefalse2truetruetrue0.01490.0149falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal annual fund operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.01240.0124falsefalsefalsetruefalse3truetruetrue0.01490.0149falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses7falseRowprimaryElement*10false0rr_FeeWaiverOrReimbursementOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue-0.0034-0.0034falsefalsefalsetruefalse2truetruetrue-0.0034-0.0034falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonPositivePure4TypepureTotal Annual Fund Operating Expenses. If there were expense reimbursement or fee waiver arrangements that reduced any Fund operating expenses and will continue to reduce them for no less than one year from the effective date of the Fund's registration statement, a Fund may add two captions to the table one caption showing the amount of the expense reimbursement or fee waiver, and a second caption showing the Fund's net expenses after subtracting the fee reimbursement or expense waiver from the total fund operating expenses. The Fund should place these additional captions directly below the "Total Annual Fund Operating Expenses" caption of the table and should use appropriate descriptive captions, such as "Fee Waiver [and/or Expense Reimbursement]" and "Total Annual Fund Operating Expenses After Fee Waiver [and/or Expense Reimbursement]," respectively. If the Fund provides this disclosure, also disclose the period for which the expense reimbursement or fee waiver arrangement is expected to continue, and briefly describe who can terminate the arrangement and under what circumstances.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseExpense reimbursement0rr_FeeWaiverOrReimbursementOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue-0.0034-0.0034falsefalsefalsetruefalse3truetruetrue-0.0034-0.0034falsefalsefalsetruefalseOthernanafalsefalseExpense reimbursement8falseRowprimaryElement*11false0rr_NetExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.0090.009falsefalsefalsetruefalse2truetruetrue0.01150.0115falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseTotal annual fund operating expenses after expense reimbursement0rr_NetExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.0090.009falsefalsefalsetruefalse3truetruetrue0.01150.0115falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses after expense reimbursement1Reflects Putnam Investment Management, LLC's contractual obligation to limit certain fund expenses through 4/30/12. This obligation may be modified or discontinued only with approval of the fund's Board of Trustees. 2Other expenses are based on estimated amounts for the current fiscal year.38Annual Fund Operating Expenses - Putnam VT Absolute Return 500 Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]9false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]10false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. Only the first year of each period in the example takes into account the expense reimbursement described above. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue9292falsefalsefalsetruefalse2truefalsetrue117117falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue347347falsefalsefalsetruefalse2truefalsetrue425425falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Absolute Return 500 Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000032103Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Absolute Return 500 Fund-Class IArr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000099977Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Absolute Return 500 FundPutnam VT Absolute Return 500 Fund-Class IAUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse2truefalsetrue9292falsefalsefalsetruefalse3truefalsetrue347347falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Absolute Return 500 Fund-Class IA2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Absolute Return 500 Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000032103Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Absolute Return 500 Fund-Class IBrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000099978Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Absolute Return 500 FundPutnam VT Absolute Return 500 Fund-Class IBUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalse2truefalsetrue117117falsefalsefalsetruefalse3truefalsetrue425425falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Absolute Return 500 Fund-Class IB32Expense Example - Putnam VT Absolute Return 500 Fund Putnam VT Absolute Return 500 Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]12false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio turnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]13false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund&#8217;s portfolio turnover rate will be available after the fund completes its first fiscal year.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]14false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00InvestmentsfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]15false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>The fund is designed to pursue a consistent absolute return by combining two independent investment strategies &#8212; a <i>beta</i> strategy, which provides broad exposure to investment markets, and an <i>alpha</i> strategy, which seeks returns from active trading. The <i>beta</i> strategy seeks to balance risk and to provide positive total return by investing, without limit, in many different asset classes, including U.S., international, and emerging markets equity securities (growth or value stocks or both) and fixed-income securities; mortgage- and asset-backed securities; high yield securities (sometimes referred to as &#8220;junk bonds&#8221;); inflation-protected securities; commodities; and real estate investment trusts. The <i>alpha</i> strategy involves the potential use of active trading strategies designed to provide additional total return through active security selection, tactical asset allocation, currency transactions and options transactions. In pursuing a consistent absolute return, the fund&#8217;s strategies are also generally intended to produce lower volatility over a reasonable period of time than has been historically associated with traditional asset classes that have earned similar levels of return over long historical periods. These traditional asset classes might include, for example, balanced portfolios with significant exposure to both stocks and bonds.</p><p>We may consider, among other factors, a company&#8217;s valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell equity investments, and, among other factors, credit, interest rate and prepayment risks when deciding whether to buy or sell fixed income investments. We may also take into account general market conditions when making investment decisions. We may use derivatives, such as futures, options, certain foreign currency transactions, warrants and swap contracts, for both hedging and non-hedging purposes in implementing the <i>beta</i> and <i>alpha</i> strategies. Accordingly, derivatives may be used to obtain or enhance exposure to the asset classes and strategies mentioned above, and to hedge against risk.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]16false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]17false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>Our allocation of assets among asset classes may hurt performance. The prices of stocks and bonds in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific issuer or industry. These risks are generally greater for small and midsize companies. Growth stocks may be more susceptible to earnings disappointments, and value stocks may fail to rebound. The market may not favor growth- or value-style investing. The risks associated with bond investments include interest rate risk, which means the prices of the fund&#8217;s investments are likely to fall if interest rates rise. Bond investments also are subject to credit risk, which is the risk that the issuers of the fund&#8217;s investments may default on payment of interest or principal. Interest rate risk is generally greater for longer-term bonds, and credit risk is generally greater for below-investment-grade bonds (&#8220;junk bonds&#8221;). Mortgage-backed investments carry the risk that they may increase in value less when interest rates decline and decline in value more when interest rates rise. We may have to invest the proceeds from prepaid investments, including mortgage- and asset-backed investments, in other investments with less attractive terms and yields. The value of international investments traded in foreign currencies may be adversely impacted by fluctuations in exchange rates. International investments may carry risks associated with potentially less stable economies or governments, such as the risk of seizure by a foreign government, the imposition of currency or other restrictions, or high levels of inflation or deflation. International investments, particularly emerging-market investments, can be illiquid. Our <i>alpha</i> strategy may lose money or not earn a return sufficient to cover associated trading and other costs. Our use of derivatives may increase these risks by, for example, increasing investment exposure or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. The fund&#8217;s efforts to produce lower volatility returns may not be successful and may make it more difficult at times for the fund to achieve its targeted return. In addition, under certain market conditions, the fund may accept greater volatility than would typically be the case, in order to seek its targeted return. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p><p><b>Investor profile</b></p><p>The fund is designed for investors seeking positive total return in excess of inflation by 500 basis points on an annualized basis over a reasonable period of time regardless of market conditions. Because the fund seeks performance over a reasonable period of time, investors should be willing to wait out short-term market fluctuations and should generally have an investment horizon of at least three years or more. The fund may be suitable for you if you are considering a balanced fund, or a fund that can manage allocations and risk across global asset classes.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]18false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]19false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Performance information will be available after the fund completes a full calendar year of operation.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalsePerformance Narrative [Text Block]20false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://putnam.com/role/riskreturnsummary1falsefalsefalse00Putnam VT American Government Income FundPutnam VT American Government Income Fundfalsefalsefalsefalsefalse2falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Putnam VT American Government Income Fund 5/1/2010 - 4/30/2011 TwelveMonthsEnded_30Apr2011_S000003871_Memberhttp://www.sec.gov/CIK0000822671duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsepvt822671_S000003871Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003871Memberdei_DocumentInformationDocumentAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0OthernaNo definition available.No authoritative reference available.falsefalsePutnam VT American Government Income Fund22false0rr_RiskReturnHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PUTNAM VT AMERICAN GOVERNMENT INCOME FUNDfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 falsefalseRisk/Return [Heading]23false0rr_ObjectiveHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00GoalfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]24false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT American Government Income Fund seeks high current income withfalsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. 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A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Secondary [Text Block]26false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and expensesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. 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Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]28false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualFundOperatingExpensesPutnamVTAmericanGovernmentIncomeFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003871_Member * row dei_LegalEntityAxis compact pvt822671_S000003871_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div 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available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)falsefalsefalsetruefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]0rr_OperatingExpensesCaptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)Annual fund operating expenses (expenses you pay each year as a percentage of the value of your investment)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOthernanafalsefalseOperating Expenses Caption [Text]2falseRowprimaryElement*5false0rr_OperatingExpensesColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherus-types:textBlockItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseShare class0rr_OperatingExpensesColumnNametruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse3falsefalsefalse00Class IBClass 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Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00200.0020falsefalsefalsetruefalse2truetruetrue0.00200.0020falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00200.0020falsefalsefalsetruefalse3truetruetrue0.00200.0020falsefalsefalsetruefalseOthernanafalsefalseOther expenses6falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00600.0060falsefalsefalsetruefalse2truetruetrue0.00850.0085falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. 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The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue6161falsefalsefalsetruefalse2truefalsetrue8787falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue192192falsefalsefalsetruefalse2truefalsetrue271271falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue335335falsefalsefalsetruefalse2truefalsetrue471471falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue750750falsefalsefalsetruefalse2truefalsetrue10511051falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT American Government Income Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003871Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT American Government Income Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010837Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT American Government Income FundPutnam VT American Government Income Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse2truefalsetrue6161falsefalsefalsetruefalse3truefalsetrue192192falsefalsefalsetruefalse4truefalsetrue335335falsefalsefalsetruefalse5truefalsetrue750750falsefalsefalsetruefalseOthernanafalsefalsePutnam VT American Government Income Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT American Government Income Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003871Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT American Government Income Fund-Class IB sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010838Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT American Government Income FundPutnam VT American Government Income Fund-Class IB sharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalse2truefalsetrue8787falsefalsefalsetruefalse3truefalsetrue271271falsefalsefalsetruefalse4truefalsetrue471471falsefalsefalsetruefalse5truefalsetrue10511051falsefalsefalsetruefalseOthernanafalsefalsePutnam VT American Government Income Fund-Class IB shares52Expense Example - Putnam VT American Government Income Fund Putnam VT American Government Income Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]32false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio turnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]33false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund&#8217;s turnover rate in the most recent fiscal year was 204%.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]34false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00InvestmentsfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]35false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in bonds and securitized debt instruments (such as mortgage-backed investments) that are obligations of the U.S. government, its agencies and instrumentalities and accordingly are backed by the full faith and credit of the United States (e.g., U.S. Treasury bonds and Ginnie Mae mortgage-backed bonds) or by only the credit of a federal agency or government-sponsored entity (e.g., Fannie Mae and Freddie Mac mortgage-backed bonds); and that have intermediate- to long-term maturities (three years or longer). We may consider, among other factors, credit, interest rate and prepayment risks, as well as general market conditions, when deciding whether to buy or sell investments. We may also use derivatives, such as futures, options and swap contracts, for both hedging and non-hedging purposes.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]36false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]37false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of bonds in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific issuer or industry. The risks associated with bond investments include interest rate risk, which means the prices of the fund&#8217;s investments are likely to fall if interest rates rise. Bond investments also are subject to credit risk, which is the risk that the issuers of the fund&#8217;s investments may default on payment of interest or principal. Credit risk is generally greater for debt not backed by the full faith and credit of the U.S. government, and interest rate risk is generally greater for longer-term bonds. Mortgage-backed investments carry the risk that they may increase in value less when interest rates decline and decline in value more when interest rates rise. We may have to invest the proceeds from prepaid investments, including mortgage- and asset-backed investments, in other investments with less attractive terms and yields. Our use of derivatives may increase these risks by, for example, increasing investment exposure or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]38false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]39false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. The performance information does not reflect insurance-related charges or expenses. If it did, performance would be lower. Please remember that past performance is not necessarily an indication of future results.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalsePerformance Narrative [Text Block]40false0rr_BarChartHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual total returns for class IA sharesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart [Heading]41false0rr_BarChartTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTAmericanGovernmentIncomeFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003871_Member * row dei_LegalEntityAxis compact pvt822671_S000003871_Member * ~&lt;/div&gt; </div>falsefalseBarChart1.jpg<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTAmericanGovernmentIncomeFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003871_Member * row dei_LegalEntityAxis compact pvt822671_S000003871_Member * ~&lt;/div&gt; </div>falsehttp://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTAmericanGovernmentIncomeFundfalsefalse0200502 - Schedule - Annual Total Returns (Bar Chart) - Putnam VT American Government Income Fundtruefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT American Government Income Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003871Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT American Government Income Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010837Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT American Government Income FundPutnam VT American Government Income Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_AnnualReturn2001rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.06820.0682falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.06820.0682falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.08980.0898falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.08980.0898falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.01890.0189falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.01890.0189falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.02850.0285falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.02850.0285falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.01650.0165falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.01650.0165falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.03500.0350falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.03500.0350falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.08630.0863falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.08630.0863falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.00540.0054falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.00540.0054falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.21350.2135falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.21350.2135falsefalsefalsetruefalseOthernanafalsefalse200910falseRowprimaryElement*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.05350.0535falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.05350.0535falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) - Putnam VT American Government Income Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]42false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>Year-to-date performance through 3/31/11</p><p>0.97%</p><p>Best calendar quarter Q1 09</p><p>5.84%</p><p>Worst calendar quarter Q2 04</p><p>-2.82%</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseBar Chart Closing [Text Block]43false0rr_AverageAnnualReturnCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Average annual total returns (<i>for periods ending 12/31/10</i>)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. 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Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]49false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT Capital Opportunities Fund seeks long-term growth of capital.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]50false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and expensesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]51false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. The fees and expenses information does not reflect insurance-related charges or expenses borne by contract holders indirectly investing in the fund. If it did, expenses would be higher.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]52false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualFundOperatingExpensesPutnamVTCapitalOpportunitiesFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003883_Member * row dei_LegalEntityAxis compact pvt822671_S000003883_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div 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available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00Annual fund operating expenses(<i>expenses you pay each year as a percentage of the value of your investment</i>)falsefalsefalsetruefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]0rr_OperatingExpensesCaptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual fund operating expenses(<i>expenses you pay each year as a percentage of the value of your investment</i>)Annual fund operating expenses(expenses you pay each year as a percentage of the value of your investment)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOthernanafalsefalseOperating Expenses Caption [Text]2falseRowprimaryElement*5false0rr_OperatingExpensesColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherus-types:textBlockItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseShare class0rr_OperatingExpensesColumnNametruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse3falsefalsefalse00Class IBClass 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Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00300.0030falsefalsefalsetruefalse2truetruetrue0.00300.0030falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00300.0030falsefalsefalsetruefalse3truetruetrue0.00300.0030falsefalsefalsetruefalseOthernanafalsefalseOther expenses6falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00930.0093falsefalsefalsetruefalse2truetruetrue0.01180.0118falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. 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The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue9595falsefalsefalsetruefalse2truefalsetrue120120falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue296296falsefalsefalsetruefalse2truefalsetrue375375falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue515515falsefalsefalsetruefalse2truefalsetrue649649falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue11431143falsefalsefalsetruefalse2truefalsetrue14361436falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. 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Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]57false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]59false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks (growth or value stocks or both) of small and midsize U.S. companies that we believe have favorable investment potential. For example, we may purchase stocks of companies with stock prices that reflect a value lower than that which we place on the company. We may also consider other factors we believe will cause the stock price to rise. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]60false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]61false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. 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inceptionfalseUSDfalsefalse$6falseColumnprimaryElement*9false0rr_AverageAnnualReturnInceptionDaterrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse002003-05-01falsefalsetruetruefalse2falsetruefalse002003-05-01falsefalsetruetruefalse3falsetruefalse002003-05-01falsefalsetruetruefalseOtherxbrli:dateItemTypedateReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 4 -Subsection b falsefalseInception DatefalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Capital Opportunities Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003883Memberdei_DocumentInformationDocumentAxisexplicitMembertruefalsePerformance 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[Heading]72false0rr_ObjectiveHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00GoalfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]73false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT Diversified Income Fund seeks as high a level of current income as Putnam Investment Management, LLC (Putnam Management) believes is consistent with preservation of capital.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]74false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and expensesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]75false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. The fees and expenses information does not reflect insurance-related charges or expenses borne by contract holders indirectly investing in the fund. If it did, expenses would be higher.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]76false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualFundOperatingExpensesPutnamVTDiversifiedIncomeFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003893_Member * row dei_LegalEntityAxis compact pvt822671_S000003893_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ 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Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00190.0019falsefalsefalsetruefalse2truetruetrue0.00190.0019falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00190.0019falsefalsefalsetruefalse3truetruetrue0.00190.0019falsefalsefalsetruefalseOthernanafalsefalseOther expenses6falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00740.0074falsefalsefalsetruefalse2truetruetrue0.00990.0099falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal annual fund operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00740.0074falsefalsefalsetruefalse3truetruetrue0.00990.0099falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses36Annual Fund Operating Expenses - Putnam VT Diversified Income Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]77false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]78false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue7676falsefalsefalsetruefalse2truefalsetrue101101falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue237237falsefalsefalsetruefalse2truefalsetrue315315falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue411411falsefalsefalsetruefalse2truefalsetrue547547falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue918918falsefalsefalsetruefalse2truefalsetrue12161216falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Diversified Income Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003893Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Diversified Income Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010881Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Diversified Income FundPutnam VT Diversified Income Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse2truefalsetrue7676falsefalsefalsetruefalse3truefalsetrue237237falsefalsefalsetruefalse4truefalsetrue411411falsefalsefalsetruefalse5truefalsetrue918918falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Diversified Income Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Diversified Income Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003893Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Diversified Income Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010882Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Diversified Income FundPutnam VT Diversified Income Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalse2truefalsetrue101101falsefalsefalsetruefalse3truefalsetrue315315falsefalsefalsetruefalse4truefalsetrue547547falsefalsefalsetruefalse5truefalsetrue12161216falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Diversified Income Fund-Class IB Shares52Expense Example - Putnam VT Diversified Income Fund Putnam VT Diversified Income Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]80false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio turnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]81false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund&#8217;s turnover rate in the most recent fiscal year was 115%.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]82false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00InvestmentsfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]83false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in bonds that are securitized debt instruments (such as mortgage-backed investments) and other obligations of companies and governments worldwide, are either investment-grade or below-investment-grade (sometimes referred to as &#8220;junk bonds&#8221;) in quality and have intermediate- to long-term maturities (three years or longer). We may consider, among other factors, credit, interest rate and prepayment risks, as well as general market conditions, when deciding whether to buy or sell investments. We may also use derivatives, such as futures, options, certain foreign currency transactions and swap contracts, for both hedging and non-hedging purposes.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]84false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]85false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of bonds in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific issuer or industry. The risks associated with bond investments include interest rate risk, which means the prices of the fund&#8217;s investments are likely to fall if interest rates rise. Bond investments also are subject to credit risk, which is the risk that the issuers of the fund&#8217;s investments may default on payment of interest or principal. Interest rate risk is generally greater for longer-term bonds, and credit risk is generally greater for below-investment-grade bonds (a significant part of the fund&#8217;s investments). Mortgage-backed investments carry the risk that they may increase in value less when interest rates decline and decline in value more when interest rates rise. We may have to invest the proceeds from prepaid investments, including mortgage- and asset-backed investments, in other investments with less attractive terms and yields. The value of international investments traded in foreign currencies may be adversely impacted by fluctuations in exchange rates. International investments may carry risks associated with potentially less stable economies or governments, such as the risk of seizure by a foreign government, the imposition of currency or other restrictions, or high levels of inflation or deflation. International investments, particularly emerging-market investments, can be illiquid. Our use of derivatives may increase these risks by, for example, increasing investment exposure or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]86false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]87false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. The performance information does not reflect insurance-related charges or expenses. If it did, performance would be lower. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.03820.0382falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.06200.0620falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.06200.0620falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.20270.2027falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.20270.2027falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.09580.0958falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.09580.0958falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.03280.0328falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.03280.0328falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.06600.0660falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.06600.0660falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.04310.0431falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.04310.0431falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.3107-0.3107falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). 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If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue7272falsefalsefalsetruefalse2truefalsetrue9797falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue224224falsefalsefalsetruefalse2truefalsetrue303303falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue390390falsefalsefalsetruefalse2truefalsetrue525525falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue871871falsefalsefalsetruefalse2truefalsetrue11691169falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. 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Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]105false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]107false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks of large U.S. companies, with a focus on value stocks that offer the potential for capital growth, current income, or both. Value stocks are issued by companies that we believe are currently undervalued by the market. If we are correct and other investors recognize the value of the company, the price of its stock may rise. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]108false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]109false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. Value stocks may fail to rebound, and the market may not favor value-style investing. Income provided by the fund may be reduced by changes in the dividend policies of, and the capital resources available at, the companies in which the fund invests.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. 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Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). 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Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue237237falsefalsefalsetruefalse2truefalsetrue315315falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue411411falsefalsefalsetruefalse2truefalsetrue547547falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue918918falsefalsefalsetruefalse2truefalsetrue12161216falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. 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Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]129false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]131false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in a combination of bonds and U.S. value stocks with a greater focus on value stocks. Value stocks are those that we believe are currently undervalued by the market. If we are correct and other investors recognize the value of the company, the price of its stock may rise. Our equity investments are mainly those in large companies, which are of a size similar to those in the Russell 1000 Value Index (which was composed of companies having a market capitalization between $193 million and $417 billion as of March 31, 2011) and midsize companies, which are of a size similar to those in the Russell Midcap Value Index (which was composed of companies having a market capitalization between $193 million and $63 billion as of March 31, 2011). We buy bonds of governments and private companies that are mostly investment-grade in quality with intermediate- to long-term maturities (three years or longer). 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These risks are generally greater for small and midsize companies. Value stocks may fail to rebound, and the market may not favor value-style investing.</p><p>The risks associated with bond investments include interest rate risk, which means the prices of the fund&#8217;s investments are likely to fall if interest rates rise. Bond investments are also subject to credit risk, which is the risk that the issuers of the fund&#8217;s investments may default on payment of interest or principal. Our use of derivatives may increase these risks by, for example, increasing investment exposure or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.04220.0422falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.12230.1223falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.12230.1223falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.01140.0114falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.01140.0114falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.4057-0.4057falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.4057-0.4057falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.26100.2610falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.26100.2610falsefalsefalsetruefalseOthernanafalsefalse200910falseRowprimaryElement*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.11200.1120falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.11200.1120falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) - Putnam VT George Putnam Balanced Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]138false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>Year-to-date performance through 3/31/11</p><p>4.44%</p><p>Best calendar quarter Q2 09</p><p>13.04%</p><p>Worst calendar quarter Q4 08</p><p>-27.53%</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseBar Chart Closing [Text Block]139false0rr_AverageAnnualReturnCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Average annual total returns (<i>for periods ending 12/31/10</i>)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 5 -Subsection b falsefalseCaption140false0rr_PerformanceTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTGeorgePutnamBalancedFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003895_Member * row dei_LegalEntityAxis compact pvt822671_S000003895_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTGeorgePutnamBalancedFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003895_Member * row dei_LegalEntityAxis compact pvt822671_S000003895_Member * ~&lt;/div&gt; </div>truehttp://putnam.com/role/AverageAnnualTotalReturnsPutnamVTGeorgePutnamBalancedFundfalsefalse0200606 - Schedule - Average Annual Total Returns - Putnam VT George Putnam Balanced Fund {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_AverageAnnualReturnLabelrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruefalse00George Putnam Blended Indexfalsefalsefalsetruefalse2falsetruefalse00Barclays Capital Aggregate Bond Indexfalsefalsefalsetruefalse3falsetruefalse00Russell 1000 Value Indexfalsefalsefalsetruefalse4falsetruefalse00Class IAfalsefalsefalsetruefalse5falsetruefalse00Class IBfalsefalsefalsetruefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalseLabelfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_IndexNoDeductionForFeesExpensesTaxesrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00(no deduction for fees or expenses)falsefalsefalsetruefalse2falsefalsefalse00(no deduction for fees or expenses)falsefalsefalsetruefalse3falsefalsefalse00(no deduction for fees or expenses)falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsetruefalseOtherxbrli:stringItemTypestringThe Performance Table includes a parenthetical, indicating that the Index "(reflects no deduction for fees, expenses or taxes)". This tag is used when this is reflected in a footnote.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 5 -Subsection b falsefalseIndex No Deduction for Fees, Expenses, Taxes [Text]falseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_AverageAnnualReturnYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.12440.1244falsefalsefalsetruefalse2truetruetrue0.06540.0654falsefalsefalsetruefalse3truetruetrue0.15510.1551falsefalsefalsetruefalse4truetruetrue0.1120.112falsefalsefalsetruefalse5truetruetrue0.10830.1083falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse1 yearfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_AverageAnnualReturnYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.04090.0409falsefalsefalsetruefalse2truetruetrue0.05800.0580falsefalsefalsetruefalse3truetruetrue0.01280.0128falsefalsefalsetruefalse4truetruetrue-0.0111-0.0111falsefalsefalsetruefalse5truetruetrue-0.0137-0.0137falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_AverageAnnualReturnYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.05010.0501falsefalsefalsetruefalse2truetruetrue0.05840.0584falsefalsefalsetruefalse3truetruetrue0.03260.0326falsefalsefalsetruefalse4truetruetrue0.01460.0146falsefalsefalsetruefalse5truetruetrue0.01190.0119falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT George Putnam Balanced Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003895Memberdei_DocumentInformationDocumentAxisexplicitMembertruefalsePerformance Measurerr_PerformanceMeasureAxisrr_PerformanceMeasureDomainrr_PerformanceMeasureAxisexplicitMemberfalsefalsePutnam VT George Putnam Balanced Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010885Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT George Putnam Balanced FundPerformance MeasurePutnam VT George Putnam Balanced Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Class IAClass IAfalsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3truetruetrue0.1120.112falsefalsefalsetruefalse4truetruetrue-0.0111-0.0111falsefalsefalsetruefalse5truetruetrue0.01460.0146falsefalsefalsetruefalseOthernanafalsefalsePutnam VT George Putnam Balanced Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT George Putnam Balanced Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003895Memberdei_DocumentInformationDocumentAxisexplicitMembertruefalsePerformance Measurerr_PerformanceMeasureAxisrr_PerformanceMeasureDomainrr_PerformanceMeasureAxisexplicitMemberfalsefalsePutnam VT George Putnam Balanced Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010886Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT George Putnam Balanced FundPerformance MeasurePutnam VT George Putnam Balanced Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Class IBClass IBfalsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3truetruetrue0.10830.1083falsefalsefalsetruefalse4truetruetrue-0.0137-0.0137falsefalsefalsetruefalse5truetruetrue0.01190.0119falsefalsefalsetruefalseOthernanafalsefalsePutnam VT George Putnam Balanced Fund-Class IB Shares3falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT George Putnam Balanced Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003895Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseRussell 1000 Value Indexrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_RussellThousandValueIndexMemberrr_PerformanceMeasureAxisexplicitMembertruefalseShare Classesrr_ProspectusShareClassAxisrr_ShareClassDomainrr_ProspectusShareClassAxisexplicitMemberPutnam VT George Putnam Balanced FundRussell 1000 Value IndexShare ClassesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Russell 1000 Value IndexRussell 1000 Value Indexfalsefalsefalsetruefalse2falsefalsefalse00(no deduction for fees or expenses)(no deduction for fees or expenses)falsefalsefalsetruefalse3truetruetrue0.15510.1551falsefalsefalsetruefalse4truetruetrue0.01280.0128falsefalsefalsetruefalse5truetruetrue0.03260.0326falsefalsefalsetruefalseOthernanafalsefalseRussell 1000 Value Index4falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT George Putnam Balanced Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003895Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseBarclays Capital Aggregate Bond Indexrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_BarclaysCapitalAggregateBondIndexMemberrr_PerformanceMeasureAxisexplicitMembertruefalseShare Classesrr_ProspectusShareClassAxisrr_ShareClassDomainrr_ProspectusShareClassAxisexplicitMemberPutnam VT George Putnam Balanced FundBarclays Capital Aggregate Bond IndexShare ClassesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Barclays Capital Aggregate Bond IndexBarclays Capital Aggregate Bond Indexfalsefalsefalsetruefalse2falsefalsefalse00(no deduction for fees or expenses)(no deduction for fees or expenses)falsefalsefalsetruefalse3truetruetrue0.06540.0654falsefalsefalsetruefalse4truetruetrue0.05800.0580falsefalsefalsetruefalse5truetruetrue0.05840.0584falsefalsefalsetruefalseOthernanafalsefalseBarclays Capital Aggregate Bond Index5falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT George Putnam Balanced Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003895Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseGeorge Putnam Blended Indexrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_GeorgePutnamBlendedIndexMemberrr_PerformanceMeasureAxisexplicitMembertruefalseShare Classesrr_ProspectusShareClassAxisrr_ShareClassDomainrr_ProspectusShareClassAxisexplicitMemberPutnam VT George Putnam Balanced FundGeorge Putnam Blended IndexShare ClassesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00George Putnam Blended IndexGeorge Putnam Blended Indexfalsefalsefalsetruefalse2falsefalsefalse00(no deduction for fees or expenses)(no deduction for fees or expenses)falsefalsefalsetruefalse3truetruetrue0.12440.1244falsefalsefalsetruefalse4truetruetrue0.04090.0409falsefalsefalsetruefalse5truetruetrue0.05010.0501falsefalsefalsetruefalseOthernanafalsefalseGeorge Putnam Blended Index55Average Annual Total Returns - Putnam VT George Putnam Balanced Fund Putnam VT George Putnam Balanced FundUnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to PerformanceTableData.No authoritative reference available.falsefalsePerformance [Table]141false0rr_PerformanceTableNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The George Putnam Blended Index is an unmanaged index administered by Putnam Management, 60% of which is the Russell 1000 Value Index and 40% of which is the Barclays Capital Aggregate Bond Index.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a table showing the Fund's (A) average annual total return; (B) average annual total return (after taxes on distributions); and (C) average annual total return (after taxes on distributions and redemption). A Money Market Fund should show only the returns described in clause (A) of the preceding sentence. All returns should be shown for 1-, 5-, and 10- calendar year periods ending on the date of the most recently completed calendar year (or for the life of the Fund, if shorter), but only for periods subsequent to the effective date of the Fund's registration statement. The table also shouldshow the returns of an appropriate broadbased securities market index as defined in Instruction 5 to Item 22(b)(7) for the same periods. A Fund that has been in existence for more than 10 years also may include returns for the life of the Fund. A Money Market Fund may provide the Fund's 7-day yield ending on the date of the most recent calendar year or disclose a toll-free (or collect) telephone number that investors can use to obtain the Fund's current 7-day yield. For a Fund (other than a Money Market Fund or a Fund described in General Instruction C.3.(d)(iii)), provide the information in the following table with the specified captions AVERAGE ANNUAL TOTAL RETURNS (For the periods ended December 31, _____). For a Fund that provides annual total returns for only one calendar year or for a Fund that does not include the bar chart because it does not have annual returns for a full calendar year, modify, as appropriate, the narrative explanation required by paragraph (c)(2)(i) (e.g., by stating that the information gives some indication of the risks of an investment in the Fund by comparing the Fund's performance with a broad measure of market performance).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iv -Subsection b falsefalsePerformance Table Narrative142false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://putnam.com/role/riskreturnsummary1falsefalsefalse00Putnam VT Global Asset Allocation FundPutnam VT Global Asset Allocation Fundfalsefalsefalsefalsefalse7falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Putnam VT Global Asset Allocation Fund 5/1/2010 - 4/30/2011 TwelveMonthsEnded_30Apr2011_S000003896_Memberhttp://www.sec.gov/CIK0000822671duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsepvt822671_S000003896Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003896Memberdei_DocumentInformationDocumentAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0OthernaNo definition available.No authoritative reference available.falsefalsePutnam VT Global Asset Allocation Fund144false0rr_RiskReturnHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PUTNAM VT GLOBAL ASSET ALLOCATION FUNDfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 falsefalseRisk/Return [Heading]145false0rr_ObjectiveHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00GoalfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]146false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT Global Asset Allocation Fund seeks long-term return consistent with preservation of capital.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]147false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and expensesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]148false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. The fees and expenses information does not reflect insurance-related charges or expenses borne by contract holders indirectly investing in the fund. If it did, expenses would be higher.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]149false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualFundOperatingExpensesPutnamVTGlobalAssetAllocationFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003896_Member * row dei_LegalEntityAxis compact pvt822671_S000003896_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div 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available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)falsefalsefalsetruefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]0rr_OperatingExpensesCaptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)Annual fund operating expenses (expenses you pay each year as a percentage of the value of your investment)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOthernanafalsefalseOperating Expenses Caption [Text]2falseRowprimaryElement*5false0rr_OperatingExpensesColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherus-types:textBlockItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseShare class0rr_OperatingExpensesColumnNametruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse3falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalseOthernanafalsefalseShare class3falseRowprimaryElement*6false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00600.0060falsefalsefalsetruefalse2truetruetrue0.00600.0060falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement 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Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00270.0027falsefalsefalsetruefalse2truetruetrue0.00270.0027falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). 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If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal annual fund operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00890.0089falsefalsefalsetruefalse3truetruetrue0.01140.0114falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses37Annual Fund Operating Expenses - Putnam VT Global Asset Allocation Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]150false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]151false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. Your actual costs may be higher or lower.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThe Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection example falsefalseExpense Example Narrative [Text Block]152false0rr_ExpenseExampleWithRedemptionTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/ExpenseExamplePutnamVTGlobalAssetAllocationFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003896_Member * row dei_LegalEntityAxis compact pvt822671_S000003896_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/ExpenseExamplePutnamVTGlobalAssetAllocationFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003896_Member * row dei_LegalEntityAxis compact pvt822671_S000003896_Member * ~&lt;/div&gt; </div>truehttp://putnam.com/role/ExpenseExamplePutnamVTGlobalAssetAllocationFundfalsefalse0200307 - Schedule - Expense Example - Putnam VT Global Asset Allocation Fund {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_ExpenseExampleByYearColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalseOtherus-types:textBlockItemTypestringThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue9191falsefalsefalsetruefalse2truefalsetrue116116falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue284284falsefalsefalsetruefalse2truefalsetrue362362falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue493493falsefalsefalsetruefalse2truefalsetrue628628falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue10961096falsefalsefalsetruefalse2truefalsetrue13901390falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Global Asset Allocation Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003896Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Global Asset Allocation Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010887Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Asset Allocation FundPutnam VT Global Asset Allocation Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse2truefalsetrue9191falsefalsefalsetruefalse3truefalsetrue284284falsefalsefalsetruefalse4truefalsetrue493493falsefalsefalsetruefalse5truefalsetrue10961096falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Global Asset Allocation Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Global Asset Allocation Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003896Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Global Asset Allocation Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010888Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Asset Allocation FundPutnam VT Global Asset Allocation Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalse2truefalsetrue116116falsefalsefalsetruefalse3truefalsetrue362362falsefalsefalsetruefalse4truefalsetrue628628falsefalsefalsetruefalse5truefalsetrue13901390falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Global Asset Allocation Fund-Class IB Shares52Expense Example - Putnam VT Global Asset Allocation Fund Putnam VT Global Asset Allocation Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]153false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio turnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]154false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund&#8217;s turnover rate in the most recent fiscal year was 159%.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]155false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00InvestmentsfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]156false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in a diversified portfolio of equity securities (growth or value stocks or both) of both U.S. and foreign companies of any size. We may consider, among other factors, a company&#8217;s valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell equity investments. We also invest in a diversified portfolio of fixed income investments, including both U.S. and foreign government obligations, corporate obligations and securitized debt instruments (such as mortgage-backed investments). We may consider, among other factors, credit, interest rate and prepayment risks, as well as general market conditions, when deciding whether to buy or sell fixed income investments. We may also select other investments that do not fall within these asset classes. We may also use derivatives, such as futures, options, certain foreign currency transactions, warrants and swap contracts, for both hedging and non-hedging purposes.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]157false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]158false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>Our allocation of assets between stocks and bonds may hurt performance. The prices of stocks and bonds in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific issuer or industry. These risks are generally greater for small and midsize companies. Growth stocks may be more susceptible to earnings disappointments, and value stocks may fail to rebound. The risks associated with bond investments include interest rate risk, which means the prices of the fund&#8217;s investments are likely to fall if interest rates rise. Bond investments also are subject to credit risk, which is the risk that the issuers of the fund&#8217;s investments may default on payment of interest or principal. Interest rate risk is generally greater for longer-term bonds, and credit risk is generally greater for below-investment-grade bonds (sometimes referred to as &#8220;junk bonds&#8221;). Mortgage-backed investments carry the risk that they may increase in value less when interest rates decline and decline in value more when interest rates rise. We may have to invest the proceeds from prepaid investments, including mortgage-and asset-backed investments, in other investments with less attractive terms and yields. The value of international investments traded in foreign currencies may be adversely impacted by fluctuations in exchange rates. International investments may carry risks associated with potentially less stable economies or governments, such as the risk of seizure by a foreign government, the imposition of currency or other restrictions, or high levels of inflation or deflation. International investments, particularly emerging-market investments, can be illiquid. Our use of derivatives may increase these risks by, for example, increasing investment exposure or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]159false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]160false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. The performance information does not reflect insurance-related charges or expenses. If it did, performance would be lower. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.0842-0.0842falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.1230-0.1230falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.1230-0.1230falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.22040.2204falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.22040.2204falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.09260.0926falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.09260.0926falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.07200.0720falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.07200.0720falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.13040.1304falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.13040.1304falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.03160.0316falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.03160.0316falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.3316-0.3316falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.3316-0.3316falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.35360.3536falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.35360.3536falsefalsefalsetruefalseOthernanafalsefalse200910falseRowprimaryElement*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.14950.1495falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.14950.1495falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) - Putnam VT Global Asset Allocation Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]163false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>Year-to-date performance through 3/31/11</p><p>4.41%</p><p>Best calendar quarter Q2 09 </p><p>16.12%</p><p>Worst calendar quarter Q4 08</p><p>-19.54%</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseBar Chart Closing [Text Block]164false0rr_AverageAnnualReturnCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Average annual total returns (<i>for periods ending 12/31/10</i>)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. 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If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalseLabelfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_IndexNoDeductionForFeesExpensesTaxesrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00(no deduction for fees or expenses)falsefalsefalsetruefalse2falsefalsefalse00(no deduction for fees or expenses; reflects deduction of withholding taxes on reinvested dividends in the case of the MSCI Index)falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalseOtherxbrli:stringItemTypestringThe Performance Table includes a parenthetical, indicating that the Index "(reflects no deduction for fees, expenses or taxes)". 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Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010888Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Asset Allocation FundPerformance MeasurePutnam VT Global Asset Allocation Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Class IBClass IBfalsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3truetruetrue0.14690.1469falsefalsefalsetruefalse4truetruetrue0.03730.0373falsefalsefalsetruefalse5truetruetrue0.03180.0318falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Global Asset Allocation Fund-Class IB Shares3falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Global Asset Allocation Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003896Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseRussell 3000 Indexrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_RussellThreeThousandIndexMemberrr_PerformanceMeasureAxisexplicitMembertruefalseShare Classesrr_ProspectusShareClassAxisrr_ShareClassDomainrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Asset Allocation FundRussell 3000 IndexShare ClassesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Russell 3000 IndexRussell 3000 Indexfalsefalsefalsetruefalse2falsefalsefalse00(no deduction for fees or expenses)(no deduction for fees or expenses)falsefalsefalsetruefalse3truetruetrue0.16930.1693falsefalsefalsetruefalse4truetruetrue0.02740.0274falsefalsefalsetruefalse5truetruetrue0.02160.0216falsefalsefalsetruefalseOthernanafalsefalseRussell 3000 Index4falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Global Asset Allocation Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003896Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam Balanced Blended Benchmarkrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_PutnamBalancedBlendedBenchmarkMemberrr_PerformanceMeasureAxisexplicitMembertruefalseShare Classesrr_ProspectusShareClassAxisrr_ShareClassDomainrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Asset Allocation FundPutnam Balanced Blended BenchmarkShare ClassesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Putnam Balanced Blended BenchmarkPutnam Balanced Blended Benchmarkfalsefalsefalsetruefalse2falsefalsefalse00(no deduction for fees or expenses; reflects deduction of withholding taxes on reinvested dividends in the case of the MSCI Index)(no deduction for fees or expenses; reflects deduction of withholding taxes on reinvested dividends in the case of the MSCI Index)falsefalsefalsetruefalse3truetruetrue0.12770.1277falsefalsefalsetruefalse4truetruetrue0.04530.0453falsefalsefalsetruefalse5truetruetrue0.04320.0432falsefalsefalsetruefalseOthernanafalsefalsePutnam Balanced Blended Benchmark54Average Annual Total Returns - Putnam VT Global Asset Allocation Fund Putnam VT Global Asset Allocation FundUnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to PerformanceTableData.No authoritative reference available.falsefalsePerformance [Table]166false0rr_PerformanceTableNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam Balanced Blended Benchmark is a benchmark administered by Putnam Management, 50% of which is the Russell 3000 Index, 35% of which is the Barclays Capital Aggregate Bond Index, 10% of which is the MSCI EAFE Index (ND) and 5% of which is the JPMorgan Developed High Yield Index.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a table showing the Fund's (A) average annual total return; (B) average annual total return (after taxes on distributions); and (C) average annual total return (after taxes on distributions and redemption). A Money Market Fund should show only the returns described in clause (A) of the preceding sentence. All returns should be shown for 1-, 5-, and 10- calendar year periods ending on the date of the most recently completed calendar year (or for the life of the Fund, if shorter), but only for periods subsequent to the effective date of the Fund's registration statement. The table also shouldshow the returns of an appropriate broadbased securities market index as defined in Instruction 5 to Item 22(b)(7) for the same periods. A Fund that has been in existence for more than 10 years also may include returns for the life of the Fund. A Money Market Fund may provide the Fund's 7-day yield ending on the date of the most recent calendar year or disclose a toll-free (or collect) telephone number that investors can use to obtain the Fund's current 7-day yield. For a Fund (other than a Money Market Fund or a Fund described in General Instruction C.3.(d)(iii)), provide the information in the following table with the specified captions AVERAGE ANNUAL TOTAL RETURNS (For the periods ended December 31, _____). For a Fund that provides annual total returns for only one calendar year or for a Fund that does not include the bar chart because it does not have annual returns for a full calendar year, modify, as appropriate, the narrative explanation required by paragraph (c)(2)(i) (e.g., by stating that the information gives some indication of the risks of an investment in the Fund by comparing the Fund's performance with a broad measure of market performance).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iv -Subsection b falsefalsePerformance Table Narrative167false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://putnam.com/role/riskreturnsummary1falsefalsefalse00Putnam VT Global Equity FundPutnam VT Global Equity Fundfalsefalsefalsefalsefalse8falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Putnam VT Global Equity Fund 5/1/2010 - 4/30/2011 TwelveMonthsEnded_30Apr2011_S000003897_Memberhttp://www.sec.gov/CIK0000822671duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsepvt822671_S000003897Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003897Memberdei_DocumentInformationDocumentAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0OthernaNo definition available.No authoritative reference available.falsefalsePutnam VT Global Equity Fund169false0rr_RiskReturnHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PUTNAM VT GLOBAL EQUITY FUNDfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 falsefalseRisk/Return [Heading]170false0rr_ObjectiveHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00GoalfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]171false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT Global Equity Fund seeks capital appreciation.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]172false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and expensesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]173false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. The fees and expenses information does not reflect insurance-related charges or expenses borne by contract holders indirectly investing in the fund. If it did, expenses would be higher.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]174false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualFundOperatingExpensesPutnamVTGlobalEquityFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003897_Member * row dei_LegalEntityAxis compact pvt822671_S000003897_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ 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FundShare ClassesStandard0falseUSDfalsefalse$2falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Global Equity Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003897Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Global Equity Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010889Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Equity FundPutnam VT Global Equity Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$3falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Global Equity Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003897Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Global Equity Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010890Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Equity FundPutnam VT Global Equity Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_OperatingExpensesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)falsefalsefalsetruefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]0rr_OperatingExpensesCaptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)Annual fund operating expenses (expenses you pay each year as a percentage of the value of your investment)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOthernanafalsefalseOperating Expenses Caption [Text]2falseRowprimaryElement*5false0rr_OperatingExpensesColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherus-types:textBlockItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseShare class0rr_OperatingExpensesColumnNametruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse3falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalseOthernanafalsefalseShare class3falseRowprimaryElement*6false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00700.0070falsefalsefalsetruefalse2truetruetrue0.00700.0070falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement fees0rr_ManagementFeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00700.0070falsefalsefalsetruefalse3truetruetrue0.00700.0070falsefalsefalsetruefalseOthernanafalsefalseManagement fees4falseRowprimaryElement*7false0rr_DistributionAndService12b1FeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruetrue00&nbsp;falsefalsefalsetruefalse2truetruetrue0.00250.0025falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureDistribution [and/or Service] (12b-1) Fees" include all distribution or other expenses incurred during the most recent fiscal year under a plan adopted pursuant to rule 12b-1 [17 CFR 270.12b-1]. Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00210.0021falsefalsefalsetruefalse2truetruetrue0.00210.0021falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00210.0021falsefalsefalsetruefalse3truetruetrue0.00210.0021falsefalsefalsetruefalseOthernanafalsefalseOther expenses6falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00910.0091falsefalsefalsetruefalse2truetruetrue0.01160.0116falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal annual fund operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00910.0091falsefalsefalsetruefalse3truetruetrue0.01160.0116falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses36Annual Fund Operating Expenses - Putnam VT Global Equity Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]175false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]176false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. Your actual costs may be higher or lower.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThe Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection example falsefalseExpense Example Narrative [Text Block]177false0rr_ExpenseExampleWithRedemptionTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/ExpenseExamplePutnamVTGlobalEquityFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003897_Member * row dei_LegalEntityAxis compact pvt822671_S000003897_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/ExpenseExamplePutnamVTGlobalEquityFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003897_Member * row dei_LegalEntityAxis compact pvt822671_S000003897_Member * ~&lt;/div&gt; </div>truehttp://putnam.com/role/ExpenseExamplePutnamVTGlobalEquityFundfalsefalse0200308 - Schedule - Expense Example - Putnam VT Global Equity Fund {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_ExpenseExampleByYearColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalseOtherus-types:textBlockItemTypestringThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue9393falsefalsefalsetruefalse2truefalsetrue118118falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue290290falsefalsefalsetruefalse2truefalsetrue368368falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue504504falsefalsefalsetruefalse2truefalsetrue638638falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue11201120falsefalsefalsetruefalse2truefalsetrue14131413falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Global Equity Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003897Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Global Equity Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010889Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Equity FundPutnam VT Global Equity Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse2truefalsetrue9393falsefalsefalsetruefalse3truefalsetrue290290falsefalsefalsetruefalse4truefalsetrue504504falsefalsefalsetruefalse5truefalsetrue11201120falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Global Equity Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Global Equity Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003897Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Global Equity Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010890Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Equity FundPutnam VT Global Equity Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalse2truefalsetrue118118falsefalsefalsetruefalse3truefalsetrue368368falsefalsefalsetruefalse4truefalsetrue638638falsefalsefalsetruefalse5truefalsetrue14131413falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Global Equity Fund-Class IB Shares52Expense Example - Putnam VT Global Equity Fund Putnam VT Global Equity Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]178false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio turnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]179false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]181false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks (growth or value stocks or both) of midsize and large companies worldwide that we believe have favorable investment potential. We may purchase stocks of companies with stock prices that reflect a value lower than that which we place on the company. We also consider other factors we believe will cause the stock price to rise. We may consider, among other factors, a company&#8217;s valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments. We invest mainly in developed countries, but may invest in emerging markets. We may also use derivatives, such as futures, options, certain foreign currency transactions, warrants and swap contracts, for both hedging and non-hedging purposes.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]182false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]183false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. Growth stocks may be more susceptible to earnings disappointments, and value stocks may fail to rebound. These risks are generally greater for small and midsize companies. The value of international investments traded in foreign currencies may be adversely impacted by fluctuations in exchange rates. International investments may carry risks associated with potentially less stable economies or governments, such as the risk of seizure by a foreign government, the imposition of currency or other restrictions, or high levels of inflation or deflation. International investments, particularly emerging-market investments, can be illiquid. Our use of derivatives may increase these risks by, for example, increasing investment exposure or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]184false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]185false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2966-0.2966falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.2216-0.2216falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2216-0.2216falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.29540.2954falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.29540.2954falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.13940.1394falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.13940.1394falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.09090.0909falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.09090.0909falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.23500.2350falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.23500.2350falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.09370.0937falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.09370.0937falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.4524-0.4524falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.4524-0.4524falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.30160.3016falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.30160.3016falsefalsefalsetruefalseOthernanafalsefalse200910falseRowprimaryElement*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.10220.1022falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.10220.1022falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) - Putnam VT Global Equity Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]188false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>Year-to-date performance through 3/31/11</p><p>9.72%</p><p>Best calendar quarter Q2 09</p><p>22.27%</p><p>Worst calendar quarter Q1 01</p><p> -25.07%</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseBar Chart Closing [Text Block]189false0rr_AverageAnnualReturnCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Average annual total returns (<i>for periods ending 12/31/10</i>)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 5 -Subsection b falsefalseCaption190false0rr_PerformanceTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTGlobalEquityFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003897_Member * row dei_LegalEntityAxis compact pvt822671_S000003897_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTGlobalEquityFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003897_Member * row dei_LegalEntityAxis compact pvt822671_S000003897_Member * ~&lt;/div&gt; </div>truehttp://putnam.com/role/AverageAnnualTotalReturnsPutnamVTGlobalEquityFundfalsefalse0200608 - Schedule - Average Annual Total Returns - Putnam VT Global Equity Fund {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_AverageAnnualReturnLabelrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruefalse00MSCI World Index (ND)falsefalsefalsetruefalse2falsetruefalse00Class IAfalsefalsefalsetruefalse3falsetruefalse00Class IBfalsefalsefalsetruefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalseLabelfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_IndexNoDeductionForFeesExpensesTaxesrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00(no deduction for fees or expenses; reflects deduction of withholding taxes on reinvested dividends)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherxbrli:stringItemTypestringThe Performance Table includes a parenthetical, indicating that the Index "(reflects no deduction for fees, expenses or taxes)". 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FundUnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to PerformanceTableData.No authoritative reference available.falsefalsePerformance [Table]191false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://putnam.com/role/riskreturnsummary1falsefalsefalse00Putnam VT Global Health Care FundPutnam VT Global Health Care Fundfalsefalsefalsefalsefalse9falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Putnam VT Global Health Care Fund 5/1/2010 - 4/30/2011 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Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]195false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT Global Health Care Fund seeks capital appreciation.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]196false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and expensesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]197false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. The fees and expenses information does not reflect insurance-related charges or expenses borne by contract holders indirectly investing in the fund. If it did, expenses would be higher.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]198false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualFundOperatingExpensesPutnamVTGlobalHealthCareFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003874_Member * row dei_LegalEntityAxis compact pvt822671_S000003874_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ 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Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003874Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Global Health Care Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010844Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Health Care FundPutnam VT Global Health Care Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_OperatingExpensesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)falsefalsefalsetruefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]0rr_OperatingExpensesCaptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)Annual fund operating expenses (expenses you pay each year as a percentage of the value of your investment)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOthernanafalsefalseOperating Expenses Caption [Text]2falseRowprimaryElement*5false0rr_OperatingExpensesColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherus-types:textBlockItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseShare class0rr_OperatingExpensesColumnNametruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse3falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalseOthernanafalsefalseShare class3falseRowprimaryElement*6false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00630.0063falsefalsefalsetruefalse2truetruetrue0.00630.0063falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement fees0rr_ManagementFeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00630.0063falsefalsefalsetruefalse3truetruetrue0.00630.0063falsefalsefalsetruefalseOthernanafalsefalseManagement fees4falseRowprimaryElement*7false0rr_DistributionAndService12b1FeesOverAssetsrrfalsenadurationNo definition 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Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00190.0019falsefalsefalsetruefalse2truetruetrue0.00190.0019falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00190.0019falsefalsefalsetruefalse3truetruetrue0.00190.0019falsefalsefalsetruefalseOthernanafalsefalseOther expenses6falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00820.0082falsefalsefalsetruefalse2truetruetrue0.01070.0107falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal annual fund operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00820.0082falsefalsefalsetruefalse3truetruetrue0.01070.0107falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses36Annual Fund Operating Expenses - Putnam VT Global Health Care Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]199false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]200false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue8484falsefalsefalsetruefalse2truefalsetrue109109falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue262262falsefalsefalsetruefalse2truefalsetrue340340falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue455455falsefalsefalsetruefalse2truefalsetrue590590falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue10141014falsefalsefalsetruefalse2truefalsetrue13091309falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Global Health Care Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003874Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Global Health Care Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010843Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Health Care FundPutnam VT Global Health Care Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse2truefalsetrue8484falsefalsefalsetruefalse3truefalsetrue262262falsefalsefalsetruefalse4truefalsetrue455455falsefalsefalsetruefalse5truefalsetrue10141014falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Global Health Care Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Global Health Care Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003874Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Global Health Care Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010844Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Health Care FundPutnam VT Global Health Care Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalse2truefalsetrue109109falsefalsefalsetruefalse3truefalsetrue340340falsefalsefalsetruefalse4truefalsetrue590590falsefalsefalsetruefalse5truefalsetrue13091309falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Global Health Care Fund-Class IB Shares52Expense Example - Putnam VT Global Health Care Fund Putnam VT Global Health Care Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]202false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio turnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]203false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund&#8217;s turnover rate in the most recent fiscal year was 33%.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]204false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00InvestmentsfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]205false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00For this non-diversified fund concentrating in the health care industries, we invest mainly in common stocks (growth or value stocks or both) of large and midsize companies worldwide that we believe have favorable investment potential. Potential investments include companies that manufacture health care supplies or provide health care-related services, and companies in the research, development, production and marketing of pharmaceuticals and biotechnology products. We may purchase stocks of companies with stock prices that reflect a value lower than that which we place on the company. We also consider other factors we believe will cause the stock price to rise. We may consider, among other factors, a company&#8217;s valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments. We may also use derivatives, such as futures, options, certain foreign currency transactions, warrants and swap contracts, for both hedging and non-hedging purposes, and may engage in short sales of securities.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]206false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]207false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. Growth stocks may be more susceptible to earnings disappointments, and value stocks may fail to rebound. The health care industries may be affected by technological obsolescence, changes in regulatory approval policies for drugs, medical devices or procedures and changes in governmental and private payment systems. Our policy of concentrating on a limited group of industries and the fund&#8217;s &#8220;non-diversified&#8221; status, which means the fund may invest in fewer issuers than a &#8220;diversified fund,&#8221; can increase the fund&#8217;s vulnerability to adverse developments affecting a single industry or issuer, which may result in greater losses and volatility for the fund. The value of international investments traded in foreign currencies may be adversely impacted by fluctuations in exchange rates. International investments may carry risks associated with potentially less stable economies or governments, such as the risk of seizure by a foreign government, the imposition of currency or other restrictions, or high levels of inflation or deflation. International investments, particularly emerging-market investments, can be illiquid. Our use of derivatives may increase these risks by, for example, increasing investment exposure or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions. Our use of short-selling may result in losses if the securities appreciate in value.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]208false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]209false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. The performance information does not reflect insurance-related charges or expenses. If it did, performance would be lower. Please remember that past performance is not necessarily an indication of future results.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalsePerformance Narrative [Text Block]210false0rr_BarChartHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual total returns for class IA sharesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart [Heading]211false0rr_BarChartTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTGlobalHealthCareFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003874_Member * row dei_LegalEntityAxis compact pvt822671_S000003874_Member * ~&lt;/div&gt; </div>falsefalseBarChart8.jpg<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTGlobalHealthCareFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003874_Member * row dei_LegalEntityAxis compact pvt822671_S000003874_Member * ~&lt;/div&gt; </div>falsehttp://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTGlobalHealthCareFundfalsefalse0200509 - Schedule - Annual Total Returns (Bar Chart) - Putnam VT Global Health Care Fundtruefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Global Health Care Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003874Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Global Health Care Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010843Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Health Care FundPutnam VT Global Health Care Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_AnnualReturn2001rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.1953-0.1953falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.1953-0.1953falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.2021-0.2021falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2021-0.2021falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.18800.1880falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.18800.1880falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.07300.0730falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.07300.0730falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.13500.1350falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.13500.1350falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.03060.0306falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.03060.0306falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.0036-0.0036falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.0036-0.0036falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.1690-0.1690falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.1690-0.1690falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.26460.2646falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.26460.2646falsefalsefalsetruefalseOthernanafalsefalse200910falseRowprimaryElement*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.02680.0268falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.02680.0268falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) - Putnam VT Global Health Care Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]212false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>Year-to-date performance through 3/31/11</p><p>6.22%</p><p>Best calendar quarter Q3 10</p><p>12.65%</p><p>Worst calendar quarter Q1 01</p><p>-22.55%</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseBar Chart Closing [Text Block]213false0rr_AverageAnnualReturnCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Average annual total returns (<i>for periods ending 12/31/10</i>)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. 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Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]221false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. The fees and expenses information does not reflect insurance-related charges or expenses borne by contract holders indirectly investing in the fund. If it did, expenses would be higher.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]222false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualFundOperatingExpensesPutnamVTGlobalUtilitiesFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003889_Member * row dei_LegalEntityAxis compact pvt822671_S000003889_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ 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Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00190.0019falsefalsefalsetruefalse2truetruetrue0.00190.0019falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00190.0019falsefalsefalsetruefalse3truetruetrue0.00190.0019falsefalsefalsetruefalseOthernanafalsefalseOther expenses6falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00820.0082falsefalsefalsetruefalse2truetruetrue0.01070.0107falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal annual fund operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00820.0082falsefalsefalsetruefalse3truetruetrue0.01070.0107falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses36Annual Fund Operating Expenses - Putnam VT Global Utilities Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]223false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]224false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue8484falsefalsefalsetruefalse2truefalsetrue109109falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue262262falsefalsefalsetruefalse2truefalsetrue340340falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue455455falsefalsefalsetruefalse2truefalsetrue590590falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue10141014falsefalsefalsetruefalse2truefalsetrue13091309falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Global Utilities Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003889Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Global Utilities Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010873Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Utilities FundPutnam VT Global Utilities Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse2truefalsetrue8484falsefalsefalsetruefalse3truefalsetrue262262falsefalsefalsetruefalse4truefalsetrue455455falsefalsefalsetruefalse5truefalsetrue10141014falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Global Utilities Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Global Utilities Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003889Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Global Utilities Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010874Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Global Utilities FundPutnam VT Global Utilities Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalse2truefalsetrue109109falsefalsefalsetruefalse3truefalsetrue340340falsefalsefalsetruefalse4truefalsetrue590590falsefalsefalsetruefalse5truefalsetrue13091309falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Global Utilities Fund-Class IB Shares52Expense Example - Putnam VT Global Utilities Fund Putnam VT Global Utilities Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]226false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio turnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]227false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund&#8217;s turnover rate in the most recent fiscal year was 34%.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]228false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00InvestmentsfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]229false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00For this non-diversified fund concentrating in the utilities industries, we invest mainly in common stocks (growth or value stocks or both) of large and midsize companies worldwide that we believe have favorable investment potential. Potential investments include electric, gas or water utilities and companies that operate as independent producers and/or distributors of power. We may purchase stocks of companies with stock prices that reflect a value lower than that which we place on the company. We also consider other factors we believe will cause the stock price to rise. We may consider, among other factors, a company&#8217;s valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments. We may also use derivatives, such as futures, options, certain foreign currency transactions, warrants and swap contracts, for both hedging and non-hedging purposes, and may engage in short sales of securities.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]230false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]231false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. Growth stocks may be more susceptible to earnings disappointments, and value stocks may fail to rebound. The utilities industries may be affected by increases in fuel costs, technological obsolescence, changes in regulatory policies and deregulation. Our policy of concentrating on a limited group of industries and the fund&#8217;s &#8220;non-diversified&#8221; status, which means the fund may invest in fewer issuers than a &#8220;diversified fund,&#8221; can increase the fund&#8217;s vulnerability to adverse developments affecting a single industry or issuer, which may result in greater losses and volatility for the fund. The value of international investments traded in foreign currencies may be adversely impacted by fluctuations in exchange rates. International investments may carry risks associated with potentially less stable economies or governments, such as the risk of seizure by a foreign government, the imposition of currency or other restrictions, or high levels of inflation or deflation. International investments, particularly emerging-market investments, can be illiquid. Our use of derivatives may increase these risks by, for example, increasing investment exposure or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions. Our use of short-selling may result in losses if the securities appreciate in value.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]232false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]233false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. The performance information does not reflect insurance-related charges or expenses. If it did, performance would be lower. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2211-0.2211falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.2383-0.2383falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2383-0.2383falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.25000.2500falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.25000.2500falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.21870.2187falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.21870.2187falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.08870.0887falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.08870.0887falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.27400.2740falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.27400.2740falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.20250.2025falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.20250.2025falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.3033-0.3033falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.3033-0.3033falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.07660.0766falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover The Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). 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Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. 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Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue202202falsefalsefalsetruefalse2truefalsetrue281281falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue351351falsefalsefalsetruefalse2truefalsetrue488488falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. 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Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]251false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]253false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks of large U.S. companies, with a focus on value stocks that offer the potential for capital growth, current income, or both. Value stocks are issued by companies that we believe are currently undervalued by the market. If we are correct and other investors recognize the value of the company, the price of its stock may rise. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]254false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]255false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. Value stocks may fail to rebound, and the market may not favor value-style investing. Income provided by the fund may be reduced by changes in the dividend policies of, and the capital resources available at, the companies in which the fund invests.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. 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Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. 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Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. 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Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00370.0037falsefalsefalsetruefalse2truetruetrue0.00370.0037falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). 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If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. 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If the Fund provides this disclosure, also disclose the period for which the expense reimbursement or fee waiver arrangement is expected to continue, and briefly describe who can terminate the arrangement and under what circumstances.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseExpense reimbursement0rr_FeeWaiverOrReimbursementOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue-0.0007-0.0007falsefalsefalsetruefalse3truetruetrue-0.0007-0.0007falsefalsefalsetruefalseOthernanafalsefalseExpense reimbursement8falseRowprimaryElement*11false0rr_NetExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00860.0086falsefalsefalsetruefalse2truetruetrue0.01110.0111falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseTotal annual fund operating expenses after expense reimbursement0rr_NetExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00860.0086falsefalsefalsetruefalse3truetruetrue0.01110.0111falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses after expense reimbursement1Reflects Putnam Management's contractual obligation to limit certain fund expenses through 4/30/12. This obligation may be modified or discontinued only with approval of the Board of Trustees.38Annual Fund Operating Expenses - Putnam VT Growth Opportunities Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]271false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]272false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. Only the first year of each period in the example takes into account the expense reimbursement described above. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue8888falsefalsefalsetruefalse2truefalsetrue113113falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue289289falsefalsefalsetruefalse2truefalsetrue368368falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue508508falsefalsefalsetruefalse2truefalsetrue642642falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue11371137falsefalsefalsetruefalse2truefalsetrue14291429falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. 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Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]275false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]277false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks of large U.S. companies, with a focus on growth stocks. Growth stocks are issued by companies whose earnings are expected to grow faster than those of similar firms, and whose business growth and other characteristics may lead to an increase in stock price. 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Growth stocks may be more susceptible to earnings disappointments, and the market may not favor growth-style investing.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). 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If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue7777falsefalsefalsetruefalse2truefalsetrue102102falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue240240falsefalsefalsetruefalse2truefalsetrue318318falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue417417falsefalsefalsetruefalse2truefalsetrue552552falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue930930falsefalsefalsetruefalse2truefalsetrue12271227falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. 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Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]300false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]302false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in bonds that are obligations of U.S. companies, are below-investment-grade in quality (sometimes referred to as &#8220;junk bonds&#8221;), and have intermediate- to long-term maturities (three years or longer). We may consider, among other factors, credit, interest rate and prepayment risks, as well as general market conditions, when deciding whether to buy or sell investments. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]303false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]304false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of bonds in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific issuer or industry. The risks associated with bond investments include interest rate risk, which means the prices of the fund&#8217;s investments are likely to fall if interest rates rise. Bond investments also are subject to credit risk, which is the risk that the issuers of the fund&#8217;s investments may default on payment of interest or principal. Interest rate risk is generally greater for longer-term bonds, and credit risk is generally greater for below-investment-grade bonds (a significant part of the fund&#8217;s investments). Our use of derivatives may increase these risks by, for example, increasing investment exposure or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]305false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]306false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. 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If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.14540.1454falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) - Putnam VT High Yield Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]309false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>Year-to-date performance through 3/31/11</p><p>3.70%</p><p>Best calendar quarter Q2 09</p><p>18.84%</p><p>Worst calendar quarter Q4 08</p><p>-19.22%</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. 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Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]316false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT Income Fund seeks high current income consistent with what Putnam Management believes to be prudent risk.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. 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Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. 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Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. 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The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). 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If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. 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Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue189189falsefalsefalsetruefalse2truefalsetrue268268falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue329329falsefalsefalsetruefalse2truefalsetrue466466falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue738738falsefalsefalsetruefalse2truefalsetrue10391039falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. 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Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]324false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]327false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]328false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of bonds in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific issuer or industry. The risks associated with bond investments include interest rate risk, which means the prices of the fund&#8217;s investments are likely to fall if interest rates rise. Bond investments also are subject to credit risk, which is the risk that the issuers of the fund&#8217;s investments may default on payment of interest or principal. Interest rate risk is generally greater for longer-term bonds, and credit risk is generally greater for below-investment-grade bonds (a significant part of the fund&#8217;s investments). Mortgage-backed investments carry the risk that they may increase in value less when interest rates decline and decline in value more when interest rates rise. Our use of derivatives may increase these risks by, for example, increasing investment exposure or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]329false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]330false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. 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The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.47220.4722falsefalsefalsetruefalseOthernanafalsefalse200910falseRowprimaryElement*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.10220.1022falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. 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The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.10220.1022falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) - Putnam VT Income Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]333false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>Year-to-date performance through 3/31/11</p><p>2.45%</p><p>Best calendar quarter Q2 09</p><p>14.35%</p><p>Worst calendar quarter Q4 08</p><p>-17.63%</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. 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Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]340false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT International Equity Fund seeks capital appreciation.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. 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Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. 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Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. 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Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue284284falsefalsefalsetruefalse2truefalsetrue362362falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue493493falsefalsefalsetruefalse2truefalsetrue628628falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue10961096falsefalsefalsetruefalse2truefalsetrue13901390falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. 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Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]348false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]350false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks (growth or value stocks or both) of large and midsize companies outside the United States that we believe have favorable investment potential. For example, we may purchase stocks of companies with stock prices that reflect a value lower than that which we place on the company. We may also consider other factors we believe will cause the stock price to rise. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]351false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]352false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. Growth stocks may be more susceptible to earnings disappointments, and value stocks may fail to rebound. The value of international investments traded in foreign currencies may be adversely impacted by fluctuations in exchange rates. International investments may carry risks associated with potentially less stable economies or governments, such as the risk of seizure by a foreign government, the imposition of currency or other restrictions, or high levels of inflation or deflation. International investments, particularly emerging-market investments, can be illiquid. Our use of derivatives may increase these risks by, for example, increasing investment exposure or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]353false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]354false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT International Equity Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003877Memberdei_DocumentInformationDocumentAxisexplicitMembertruefalsePerformance Measurerr_PerformanceMeasureAxisrr_PerformanceMeasureDomainrr_PerformanceMeasureAxisexplicitMemberfalsefalsePutnam VT International Equity Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010849Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT International Equity FundPerformance MeasurePutnam VT International Equity Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Class IAClass 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Equity FundPerformance MeasurePutnam VT International Equity Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Class IBClass IBfalsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3truetruetrue0.10030.1003falsefalsefalsetruefalse4truetruetrue0.01240.0124falsefalsefalsetruefalse5truetruetrue0.01540.0154falsefalsefalsetruefalseOthernanafalsefalsePutnam VT International Equity Fund-Class IB Shares3falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT International Equity Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003877Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseMSCI EAFE 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FundUnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to PerformanceTableData.No authoritative reference available.falsefalsePerformance [Table]360false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://putnam.com/role/riskreturnsummary1falsefalsefalse00Putnam VT International Growth FundPutnam VT International Growth Fundfalsefalsefalsefalsefalse16falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Putnam VT International Growth Fund 5/1/2010 - 4/30/2011 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Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]364false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT International Growth Fund seeks long-term capital appreciation.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. 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Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]366false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. The fees and expenses information does not reflect insurance-related charges or expenses borne by contract holders indirectly investing in the fund. If it did, expenses would be higher.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]367false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualFundOperatingExpensesPutnamVTInternationalGrowthFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003879_Member * row dei_LegalEntityAxis compact pvt822671_S000003879_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div 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Classesrr_ProspectusShareClassAxisrr_ShareClassDomainrr_ProspectusShareClassAxisexplicitMemberPutnam VT International Growth FundShare ClassesStandard0falseUSDfalsefalse$2falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT International Growth Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003879Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT International Growth Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010853Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT International Growth FundPutnam VT International Growth Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$3falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT International Growth Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003879Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT International Growth Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010854Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT International Growth FundPutnam VT International Growth Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_OperatingExpensesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)[1]falsefalsefalsetruefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]0rr_OperatingExpensesCaptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse[1]1falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)Annual fund operating expenses (expenses you pay each year as a percentage of the value of your investment)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOthernanafalsefalseOperating Expenses Caption [Text]2falseRowprimaryElement*5false0rr_OperatingExpensesColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherus-types:textBlockItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseShare class0rr_OperatingExpensesColumnNametruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse3falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalseOthernanafalsefalseShare class3falseRowprimaryElement*6false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00930.0093falsefalsefalsetruefalse2truetruetrue0.00930.0093falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement fees0rr_ManagementFeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00930.0093falsefalsefalsetruefalse3truetruetrue0.00930.0093falsefalsefalsetruefalseOthernanafalsefalseManagement fees4falseRowprimaryElement*7false0rr_DistributionAndService12b1FeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruetrue00&nbsp;falsefalsefalsetruefalse2truetruetrue0.00250.0025falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureDistribution [and/or Service] (12b-1) Fees" include all distribution or other expenses incurred during the most recent fiscal year under a plan adopted pursuant to rule 12b-1 [17 CFR 270.12b-1]. Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00310.0031falsefalsefalsetruefalse2truetruetrue0.00310.0031falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00310.0031falsefalsefalsetruefalse3truetruetrue0.00310.0031falsefalsefalsetruefalseOthernanafalsefalseOther expenses6falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.01240.0124falsefalsefalsetruefalse2truetruetrue0.01490.0149falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal annual fund operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.01240.0124falsefalsefalsetruefalse3truetruetrue0.01490.0149falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses7falseRowprimaryElement*10false0rr_FeeWaiverOrReimbursementOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue-0.0001-0.0001falsefalsefalsetruefalse2truetruetrue-0.0001-0.0001falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonPositivePure4TypepureTotal Annual Fund Operating Expenses. If there were expense reimbursement or fee waiver arrangements that reduced any Fund operating expenses and will continue to reduce them for no less than one year from the effective date of the Fund's registration statement, a Fund may add two captions to the table one caption showing the amount of the expense reimbursement or fee waiver, and a second caption showing the Fund's net expenses after subtracting the fee reimbursement or expense waiver from the total fund operating expenses. The Fund should place these additional captions directly below the "Total Annual Fund Operating Expenses" caption of the table and should use appropriate descriptive captions, such as "Fee Waiver [and/or Expense Reimbursement]" and "Total Annual Fund Operating Expenses After Fee Waiver [and/or Expense Reimbursement]," respectively. If the Fund provides this disclosure, also disclose the period for which the expense reimbursement or fee waiver arrangement is expected to continue, and briefly describe who can terminate the arrangement and under what circumstances.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseExpense reimbursement0rr_FeeWaiverOrReimbursementOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue-0.0001-0.0001falsefalsefalsetruefalse3truetruetrue-0.0001-0.0001falsefalsefalsetruefalseOthernanafalsefalseExpense reimbursement8falseRowprimaryElement*11false0rr_NetExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.01230.0123falsefalsefalsetruefalse2truetruetrue0.01480.0148falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 11 -Subsection table falsefalseTotal annual fund operating expenses after expense reimbursement0rr_NetExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.01230.0123falsefalsefalsetruefalse3truetruetrue0.01480.0148falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses after expense reimbursement1Reflects Putnam Management's contractual obligation to limit certain fund expenses through 4/30/12. This obligation may be modified or discontinued only with approval of the Board of Trustees.38Annual Fund Operating Expenses - Putnam VT International Growth Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]368false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]369false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. Only the first year of each period in the example takes into account the expense reimbursement described above. Your actual costs may be higher or lower.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThe Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection example falsefalseExpense Example Narrative [Text Block]370false0rr_ExpenseExampleWithRedemptionTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/ExpenseExamplePutnamVTInternationalGrowthFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003879_Member * row dei_LegalEntityAxis compact pvt822671_S000003879_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/ExpenseExamplePutnamVTInternationalGrowthFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003879_Member * row dei_LegalEntityAxis compact pvt822671_S000003879_Member * ~&lt;/div&gt; </div>truehttp://putnam.com/role/ExpenseExamplePutnamVTInternationalGrowthFundfalsefalse0200316 - Schedule - Expense Example - Putnam VT International Growth Fund {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_ExpenseExampleByYearColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalseOtherus-types:textBlockItemTypestringThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue125125falsefalsefalsetruefalse2truefalsetrue151151falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue392392falsefalsefalsetruefalse2truefalsetrue470470falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue680680falsefalsefalsetruefalse2truefalsetrue812812falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue14991499falsefalsefalsetruefalse2truefalsetrue17851785falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT International Growth Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003879Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT International Growth Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010853Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT International Growth FundPutnam VT International Growth Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse2truefalsetrue125125falsefalsefalsetruefalse3truefalsetrue392392falsefalsefalsetruefalse4truefalsetrue680680falsefalsefalsetruefalse5truefalsetrue14991499falsefalsefalsetruefalseOthernanafalsefalsePutnam VT International Growth Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT International Growth Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003879Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT International Growth Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010854Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT International Growth FundPutnam VT International Growth Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalse2truefalsetrue151151falsefalsefalsetruefalse3truefalsetrue470470falsefalsefalsetruefalse4truefalsetrue812812falsefalsefalsetruefalse5truefalsetrue17851785falsefalsefalsetruefalseOthernanafalsefalsePutnam VT International Growth Fund-Class IB Shares52Expense Example - Putnam VT International Growth Fund Putnam VT International Growth Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]371false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio turnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]372false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund&#8217;s turnover rate in the most recent fiscal year was 148%.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]373false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00InvestmentsfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]374false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks of companies of any size in established and emerging markets outside the United States. We invest mainly in growth stocks, which are issued by companies whose earnings are expected to grow faster than those of similar firms, and whose business growth and other characteristics may lead to an increase in stock price. We may consider, among other factors, a company&#8217;s valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments. We may also use derivatives, such as futures, options, certain foreign currency transactions, warrants and swap contracts, for both hedging and non-hedging purposes.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]375false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]376false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. These risks are generally greater for small and midsize companies. Growth stocks may be more susceptible to earnings disappointments. The value of international investments traded in foreign currencies may be adversely impacted by fluctuations in exchange rates. International investments may carry risks associated with potentially less stable economies or governments, such as the risk of seizure by a foreign government, the imposition of currency or other restrictions, or high levels of inflation or deflation. International investments, particularly emerging-market investments, can be illiquid. Our use of derivatives may increase these risks by, for example, increasing investment exposure or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]377false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]378false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. The performance information does not reflect insurance-related charges or expenses. If it did, performance would be lower. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2852-0.2852falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.1346-0.1346falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.1346-0.1346falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.33590.3359falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.33590.3359falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.13630.1363falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.13630.1363falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.18640.1864falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.18640.1864falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.26420.2642falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.26420.2642falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.13520.1352falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.13520.1352falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.4236-0.4236falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.4236-0.4236falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.38760.3876falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.38760.3876falsefalsefalsetruefalseOthernanafalsefalse200910falseRowprimaryElement*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.12480.1248falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.12480.1248falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) - Putnam VT International Growth Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]381false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>Year-to-date performance through 3/31/11</p><p>4.06%</p><p>Best calendar quarter Q2 09</p><p>23.00%</p><p>Worst calendar quarter Q4 08</p><p>-22.61%</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseBar Chart Closing [Text Block]382false0rr_AverageAnnualReturnCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Average annual total returns (<i>for periods ending 12/31/10</i>)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 5 -Subsection b falsefalseCaption383false0rr_PerformanceTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTInternationalGrowthFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003879_Member * row dei_LegalEntityAxis compact pvt822671_S000003879_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTInternationalGrowthFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003879_Member * row dei_LegalEntityAxis compact pvt822671_S000003879_Member * ~&lt;/div&gt; </div>truehttp://putnam.com/role/AverageAnnualTotalReturnsPutnamVTInternationalGrowthFundfalsefalse0200616 - Schedule - Average Annual Total Returns - Putnam VT International Growth Fund {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_AverageAnnualReturnLabelrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruefalse00MSCI EAFE Growth Index (ND)falsefalsefalsetruefalse2falsetruefalse00Class IAfalsefalsefalsetruefalse3falsetruefalse00Class IBfalsefalsefalsetruefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalseLabelfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_IndexNoDeductionForFeesExpensesTaxesrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00(no deduction for fees or expenses; reflects deduction of withholding taxes on reinvested dividends)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherxbrli:stringItemTypestringThe Performance Table includes a parenthetical, indicating that the Index "(reflects no deduction for fees, expenses or taxes)". This tag is used when this is reflected in a footnote.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 5 -Subsection b falsefalseIndex No Deduction for Fees, Expenses, Taxes [Text]falseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_AverageAnnualReturnYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.12250.1225falsefalsefalsetruefalse2truetruetrue0.12480.1248falsefalsefalsetruefalse3truetruetrue0.12200.1220falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse1 yearfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_AverageAnnualReturnYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.03460.0346falsefalsefalsetruefalse2truetruetrue0.05240.0524falsefalsefalsetruefalse3truetruetrue0.04980.0498falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_AverageAnnualReturnYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.02690.0269falsefalsefalsetruefalse2truetruetrue0.03700.0370falsefalsefalsetruefalse3truetruetrue0.03450.0345falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT International Growth Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003879Memberdei_DocumentInformationDocumentAxisexplicitMembertruefalsePerformance Measurerr_PerformanceMeasureAxisrr_PerformanceMeasureDomainrr_PerformanceMeasureAxisexplicitMemberfalsefalsePutnam VT International Growth Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010853Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT International Growth FundPerformance MeasurePutnam VT International Growth Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Class IAClass 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Indexrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_MSCIEAFEGrowthIndexMemberrr_PerformanceMeasureAxisexplicitMembertruefalseShare Classesrr_ProspectusShareClassAxisrr_ShareClassDomainrr_ProspectusShareClassAxisexplicitMemberPutnam VT International Growth FundMSCI EAFE Growth IndexShare ClassesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00MSCI EAFE Growth Index (ND)MSCI EAFE Growth Index (ND)falsefalsefalsetruefalse2falsefalsefalse00(no deduction for fees or expenses; reflects deduction of withholding taxes on reinvested dividends)(no deduction for fees or expenses; reflects deduction of withholding taxes on reinvested dividends)falsefalsefalsetruefalse3truetruetrue0.12250.1225falsefalsefalsetruefalse4truetruetrue0.03460.0346falsefalsefalsetruefalse5truetruetrue0.02690.0269falsefalsefalsetruefalseOthernanafalsefalseMSCI EAFE Growth Index53Average Annual Total Returns - Putnam VT International Growth Fund Putnam VT International Growth FundUnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to PerformanceTableData.No authoritative reference available.falsefalsePerformance [Table]384false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://putnam.com/role/riskreturnsummary1falsefalsefalse00Putnam VT International Value FundPutnam VT International Value Fundfalsefalsefalsefalsefalse17falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Putnam VT International Value Fund 5/1/2010 - 4/30/2011 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[Heading]387false0rr_ObjectiveHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00GoalfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]388false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT International Value Fund seeks capital growth.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. 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Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. 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Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. 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available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)falsefalsefalsetruefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]0rr_OperatingExpensesCaptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)Annual fund operating expenses (expenses you pay each year as a percentage of the value of your investment)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOthernanafalsefalseOperating Expenses Caption [Text]2falseRowprimaryElement*5false0rr_OperatingExpensesColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherus-types:textBlockItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseShare class0rr_OperatingExpensesColumnNametruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse3falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalseOthernanafalsefalseShare class3falseRowprimaryElement*6false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00700.0070falsefalsefalsetruefalse2truetruetrue0.00700.0070falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement 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Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00210.0021falsefalsefalsetruefalse2truetruetrue0.00210.0021falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00210.0021falsefalsefalsetruefalse3truetruetrue0.00210.0021falsefalsefalsetruefalseOthernanafalsefalseOther expenses6falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00910.0091falsefalsefalsetruefalse2truetruetrue0.01160.0116falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal annual fund operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00910.0091falsefalsefalsetruefalse3truetruetrue0.01160.0116falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses36Annual Fund Operating Expenses - Putnam VT International Value Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]393false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]394false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue9393falsefalsefalsetruefalse2truefalsetrue118118falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue290290falsefalsefalsetruefalse2truefalsetrue368368falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue504504falsefalsefalsetruefalse2truefalsetrue638638falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue11201120falsefalsefalsetruefalse2truefalsetrue14131413falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT International Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003878Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT International Value Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010851Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT International Value FundPutnam VT International Value Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse2truefalsetrue9393falsefalsefalsetruefalse3truefalsetrue290290falsefalsefalsetruefalse4truefalsetrue504504falsefalsefalsetruefalse5truefalsetrue11201120falsefalsefalsetruefalseOthernanafalsefalsePutnam VT International Value Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT International Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003878Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT International Value Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010852Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT International Value FundPutnam VT International Value Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalse2truefalsetrue118118falsefalsefalsetruefalse3truefalsetrue368368falsefalsefalsetruefalse4truefalsetrue638638falsefalsefalsetruefalse5truefalsetrue14131413falsefalsefalsetruefalseOthernanafalsefalsePutnam VT International Value Fund-Class IB Shares52Expense Example - Putnam VT International Value Fund Putnam VT International Value Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]396false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio turnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]397false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund&#8217;s turnover rate in the most recent fiscal year was 52%.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]398false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00InvestmentsfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]399false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks of companies outside the United States, with a focus on value stocks. Value stocks are those that we believe are currently undervalued by the market. If we are correct and other investors recognize the value of the company, the price of its stock may rise. We invest mainly in midsize and large companies, although we can invest in companies of any size. We invest mainly in developed countries, but may invest in emerging markets. We may consider, among other factors, a company&#8217;s valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments. We may also use derivatives, such as futures, options, certain foreign currency transactions, warrants and swap contracts, for both hedging and non-hedging purposes.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]400false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]401false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. Value stocks may fail to rebound, and the market may not favor value-style investing. The value of international investments traded in foreign currencies may be adversely impacted by fluctuations in exchange rates. International investments may carry risks associated with potentially less stable economies or governments, such as the risk of seizure by a foreign government, the imposition of currency or other restrictions, or high levels of inflation or deflation. International investments, particularly emerging-market investments, can be illiquid. Our use of derivatives may increase these risks by, for example, increasing investment exposure or, in the case of many over-the-counter instruments, because of the potential inability to terminate or sell derivatives positions.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]402false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]403false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. The performance information does not reflect insurance-related charges or expenses. If it did, performance would be lower. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2067-0.2067falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.1367-0.1367falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.1367-0.1367falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.38370.3837falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.38370.3837falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.21310.2131falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.21310.2131falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.14330.1433falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.14330.1433falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.27630.2763falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.27630.2763falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.07290.0729falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.07290.0729falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.4585-0.4585falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.4585-0.4585falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.26390.2639falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.26390.2639falsefalsefalsetruefalseOthernanafalsefalse200910falseRowprimaryElement*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.07420.0742falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.07420.0742falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) - Putnam VT International Value Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]406false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>Year-to-date performance through 3/31/11</p><p>3.43%</p><p>Best calendar quarter Q2 09</p><p>23.79%</p><p>Worst calendar quarter Q4 08</p><p>-23.24%</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. 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If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalseLabelfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_IndexNoDeductionForFeesExpensesTaxesrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00(no deduction for fees or expenses; reflects deduction of withholding taxes on reinvested dividends)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00(no deduction for fees or expenses)falsefalsefalsetruefalseOtherxbrli:stringItemTypestringThe Performance Table includes a parenthetical, indicating that the Index "(reflects no deduction for fees, expenses or taxes)". 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Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003878Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseMSCI EAFE Value Indexrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_MSCIEAFEValueIndexMemberrr_PerformanceMeasureAxisexplicitMembertruefalseShare Classesrr_ProspectusShareClassAxisrr_ShareClassDomainrr_ProspectusShareClassAxisexplicitMemberPutnam VT International Value FundMSCI EAFE Value IndexShare ClassesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00MSCI EAFE Value Index (ND)MSCI EAFE Value Index (ND)falsefalsefalsetruefalse2falsefalsefalse00(no deduction for fees or expenses; reflects deduction of withholding taxes on reinvested dividends)(no deduction for fees or expenses; reflects deduction of withholding taxes on reinvested dividends)falsefalsefalsetruefalse3truetruetrue0.03250.0325falsefalsefalsetruefalse4truetruetrue0.01370.0137falsefalsefalsetruefalse5truetruetrue0.04190.0419falsefalsefalsetruefalseOthernanafalsefalseMSCI EAFE Value Index4falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT International Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003878Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseS&P Developed Ex-U.S. LargeMidCap Value Indexrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_SAndPDevelopedExUSLargeMidCapValueIndexMemberrr_PerformanceMeasureAxisexplicitMembertruefalseShare Classesrr_ProspectusShareClassAxisrr_ShareClassDomainrr_ProspectusShareClassAxisexplicitMemberPutnam VT International Value FundS&P Developed Ex-U.S. LargeMidCap Value IndexShare ClassesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00S&P Developed Ex-U.S. LargeMidCap Value IndexS&P Developed Ex-U.S. LargeMidCap Value Indexfalsefalsefalsetruefalse2falsefalsefalse00(no deduction for fees or expenses)(no deduction for fees or expenses)falsefalsefalsetruefalse3truetruetrue0.10020.1002falsefalsefalsetruefalse4truetruetrue0.03810.0381falsefalsefalsetruefalse5truetruetrue0.05870.0587falsefalsefalsetruefalseOthernanafalsefalseS&P Developed Ex-U.S. LargeMidCap Value Index54Average Annual Total Returns - Putnam VT International Value Fund Putnam VT International Value FundUnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to PerformanceTableData.No authoritative reference available.falsefalsePerformance [Table]409false0rr_PerformanceTableNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The MSCI EAFE Value Index (ND) will replace the S&P Developed Ex-U.S. LargeMidCap Value Index as the benchmark for this fund because, in Putnam Management&#8217;s opinion, the securities tracked by this index more accurately reflect the types of securities that generally will be held by the fund.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a table showing the Fund's (A) average annual total return; (B) average annual total return (after taxes on distributions); and (C) average annual total return (after taxes on distributions and redemption). A Money Market Fund should show only the returns described in clause (A) of the preceding sentence. All returns should be shown for 1-, 5-, and 10- calendar year periods ending on the date of the most recently completed calendar year (or for the life of the Fund, if shorter), but only for periods subsequent to the effective date of the Fund's registration statement. The table also shouldshow the returns of an appropriate broadbased securities market index as defined in Instruction 5 to Item 22(b)(7) for the same periods. A Fund that has been in existence for more than 10 years also may include returns for the life of the Fund. A Money Market Fund may provide the Fund's 7-day yield ending on the date of the most recent calendar year or disclose a toll-free (or collect) telephone number that investors can use to obtain the Fund's current 7-day yield. For a Fund (other than a Money Market Fund or a Fund described in General Instruction C.3.(d)(iii)), provide the information in the following table with the specified captions AVERAGE ANNUAL TOTAL RETURNS (For the periods ended December 31, _____). For a Fund that provides annual total returns for only one calendar year or for a Fund that does not include the bar chart because it does not have annual returns for a full calendar year, modify, as appropriate, the narrative explanation required by paragraph (c)(2)(i) (e.g., by stating that the information gives some indication of the risks of an investment in the Fund by comparing the Fund's performance with a broad measure of market performance).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iv -Subsection b falsefalsePerformance Table Narrative410false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://putnam.com/role/riskreturnsummary1falsefalsefalse00Putnam VT Investors FundPutnam VT Investors Fundfalsefalsefalsefalsefalse18falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Putnam VT Investors Fund 5/1/2010 - 4/30/2011 TwelveMonthsEnded_30Apr2011_S000003880_Memberhttp://www.sec.gov/CIK0000822671duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsepvt822671_S000003880Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003880Memberdei_DocumentInformationDocumentAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0OthernaNo definition available.No authoritative reference available.falsefalsePutnam VT Investors Fund412false0rr_RiskReturnHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PUTNAM VT INVESTORS FUNDfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 falsefalseRisk/Return [Heading]413false0rr_ObjectiveHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00GoalfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]414false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT Investors Fund seeks long-term growth of capital and any increased income that results from this growth.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]415false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and expensesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]416false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. The fees and expenses information does not reflect insurance-related charges or expenses borne by contract holders indirectly investing in the fund. If it did, expenses would be higher.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]417false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualFundOperatingExpensesPutnamVTInvestorsFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003880_Member * row dei_LegalEntityAxis compact pvt822671_S000003880_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ 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ClassesStandard0falseUSDfalsefalse$2falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Investors Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003880Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Investors Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010855Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Investors FundPutnam VT Investors Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$3falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Investors Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003880Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Investors Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010856Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Investors FundPutnam VT Investors Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_OperatingExpensesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)falsefalsefalsetruefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]0rr_OperatingExpensesCaptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)Annual fund operating expenses (expenses you pay each year as a percentage of the value of your investment)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOthernanafalsefalseOperating Expenses Caption [Text]2falseRowprimaryElement*5false0rr_OperatingExpensesColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherus-types:textBlockItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseShare class0rr_OperatingExpensesColumnNametruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse3falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalseOthernanafalsefalseShare class3falseRowprimaryElement*6false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00560.0056falsefalsefalsetruefalse2truetruetrue0.00560.0056falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement fees0rr_ManagementFeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00560.0056falsefalsefalsetruefalse3truetruetrue0.00560.0056falsefalsefalsetruefalseOthernanafalsefalseManagement fees4falseRowprimaryElement*7false0rr_DistributionAndService12b1FeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruetrue00&nbsp;falsefalsefalsetruefalse2truetruetrue0.00250.0025falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureDistribution [and/or Service] (12b-1) Fees" include all distribution or other expenses incurred during the most recent fiscal year under a plan adopted pursuant to rule 12b-1 [17 CFR 270.12b-1]. Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00170.0017falsefalsefalsetruefalse2truetruetrue0.00170.0017falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00170.0017falsefalsefalsetruefalse3truetruetrue0.00170.0017falsefalsefalsetruefalseOthernanafalsefalseOther expenses6falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00730.0073falsefalsefalsetruefalse2truetruetrue0.00980.0098falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal annual fund operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00730.0073falsefalsefalsetruefalse3truetruetrue0.00980.0098falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses36Annual Fund Operating Expenses - Putnam VT Investors Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]418false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]419false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. Your actual costs may be higher or lower.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThe Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection example falsefalseExpense Example Narrative [Text Block]420false0rr_ExpenseExampleWithRedemptionTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/ExpenseExamplePutnamVTInvestorsFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003880_Member * row dei_LegalEntityAxis compact pvt822671_S000003880_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/ExpenseExamplePutnamVTInvestorsFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003880_Member * row dei_LegalEntityAxis compact pvt822671_S000003880_Member * ~&lt;/div&gt; </div>truehttp://putnam.com/role/ExpenseExamplePutnamVTInvestorsFundfalsefalse0200318 - Schedule - Expense Example - Putnam VT Investors Fund {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_ExpenseExampleByYearColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalseOtherus-types:textBlockItemTypestringThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue7575falsefalsefalsetruefalse2truefalsetrue100100falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue233233falsefalsefalsetruefalse2truefalsetrue312312falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue406406falsefalsefalsetruefalse2truefalsetrue542542falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue906906falsefalsefalsetruefalse2truefalsetrue12041204falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Investors Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003880Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Investors Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010855Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Investors FundPutnam VT Investors Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse2truefalsetrue7575falsefalsefalsetruefalse3truefalsetrue233233falsefalsefalsetruefalse4truefalsetrue406406falsefalsefalsetruefalse5truefalsetrue906906falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Investors Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Investors Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003880Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Investors Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010856Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Investors FundPutnam VT Investors Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalse2truefalsetrue100100falsefalsefalsetruefalse3truefalsetrue312312falsefalsefalsetruefalse4truefalsetrue542542falsefalsefalsetruefalse5truefalsetrue12041204falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Investors Fund-Class IB Shares52Expense Example - Putnam VT Investors Fund Putnam VT Investors Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]421false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio turnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]422false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]424false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks (growth or value stocks or both) of large U.S. companies that we believe have favorable investment potential. For example, we may purchase stocks of companies with stock prices that reflect a value lower than that which we place on the company. We may also consider other factors we believe will cause the stock price to rise. We may consider, among other factors, a company&#8217;s valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]425false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]426false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. Growth stocks may be more susceptible to earnings disappointments, and value stocks may fail to rebound.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]427false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]428false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. The performance information does not reflect insurance-related charges or expenses. If it did, performance would be lower. Please remember that past performance is not necessarily an indication of future results.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalsePerformance Narrative [Text Block]429false0rr_BarChartHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual total returns for class IA sharesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart [Heading]430false0rr_BarChartTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTInvestorsFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003880_Member * row dei_LegalEntityAxis compact pvt822671_S000003880_Member * ~&lt;/div&gt; </div>falsefalseBarChart17.jpg<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTInvestorsFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003880_Member * row dei_LegalEntityAxis compact pvt822671_S000003880_Member * ~&lt;/div&gt; </div>falsehttp://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTInvestorsFundfalsefalse0200518 - Schedule - Annual Total Returns (Bar Chart) - Putnam VT Investors Fundtruefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Investors Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003880Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Investors Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010855Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Investors FundPutnam VT Investors Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_AnnualReturn2001rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.2461-0.2461falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2461-0.2461falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.2368-0.2368falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2368-0.2368falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.27390.2739falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.27390.2739falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.12950.1295falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.12950.1295falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.09030.0903falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.09030.0903falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.14240.1424falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.14240.1424falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.0490-0.0490falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.0490-0.0490falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.3944-0.3944falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.3944-0.3944falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.31180.3118falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.31180.3118falsefalsefalsetruefalseOthernanafalsefalse200910falseRowprimaryElement*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.14240.1424falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.14240.1424falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) - Putnam VT Investors Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]431false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>Year-to-date performance through 3/31/11</p><p>6.27%</p><p>Best calendar quarter Q2 09</p><p>18.61%</p><p>Worst calendar quarter Q4 08</p><p>-21.46%</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseBar Chart Closing [Text Block]432false0rr_AverageAnnualReturnCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Average annual total returns (<i>for periods ending 12/31/10</i>)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 5 -Subsection b falsefalseCaption433false0rr_PerformanceTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTInvestorsFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003880_Member * row dei_LegalEntityAxis compact pvt822671_S000003880_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTInvestorsFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003880_Member * row dei_LegalEntityAxis compact pvt822671_S000003880_Member * ~&lt;/div&gt; </div>truehttp://putnam.com/role/AverageAnnualTotalReturnsPutnamVTInvestorsFundfalsefalse0200618 - Schedule - Average Annual Total Returns - Putnam VT Investors Fund {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_AverageAnnualReturnLabelrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruefalse00Class IAfalsefalsefalsetruefalse2falsetruefalse00Class IBfalsefalsefalsetruefalse3falsetruefalse00S&P 500 IndexfalsefalsefalsetruefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalseLabelfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_IndexNoDeductionForFeesExpensesTaxesrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00(no deduction for fees or expenses)falsefalsefalsetruefalseOtherxbrli:stringItemTypestringThe Performance Table includes a parenthetical, indicating that the Index "(reflects no deduction for fees, expenses or taxes)". 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available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue-0.0028-0.0028falsefalsefalsetruefalse2truetruetrue-0.0054-0.0054falsefalsefalsetruefalse3truetruetrue0.02290.0229falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_AverageAnnualReturnYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue-0.0116-0.0116falsefalsefalsetruefalse2truetruetrue-0.0140-0.0140falsefalsefalsetruefalse3truetruetrue0.01410.0141falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Investors Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003880Memberdei_DocumentInformationDocumentAxisexplicitMembertruefalsePerformance Measurerr_PerformanceMeasureAxisrr_PerformanceMeasureDomainrr_PerformanceMeasureAxisexplicitMemberfalsefalsePutnam VT Investors Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010855Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Investors FundPerformance MeasurePutnam VT Investors Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Class IAClass 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authoritative reference available.falsefalsePerformance [Table]434false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://putnam.com/role/riskreturnsummary1falsefalsefalse00Putnam VT Money Market FundPutnam VT Money Market Fundfalsefalsefalsefalsefalse19falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Putnam VT Money Market Fund 5/1/2010 - 4/30/2011 TwelveMonthsEnded_30Apr2011_S000003882_Memberhttp://www.sec.gov/CIK0000822671duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsepvt822671_S000003882Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003882Memberdei_DocumentInformationDocumentAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0OthernaNo definition available.No authoritative reference available.falsefalsePutnam VT Money Market Fund436false0rr_RiskReturnHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PUTNAM VT MONEY MARKET FUNDfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 falsefalseRisk/Return [Heading]437false0rr_ObjectiveHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00GoalfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]438false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT Money Market Fund seeks as high a rate of current income as we believe is consistent with preservation of capital and maintenance of liquidity.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]439false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and expensesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]440false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. The fees and expenses information does not reflect insurance-related charges or expenses borne by contract holders indirectly investing in the fund. If it did, expenses would be higher.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]441false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualFundOperatingExpensesPutnamVTMoneyMarketFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003882_Member * row dei_LegalEntityAxis compact pvt822671_S000003882_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ 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Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003882Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Money Market Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010860Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Money Market FundPutnam VT Money Market Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_OperatingExpensesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)falsefalsefalsetruefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]0rr_OperatingExpensesCaptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)Annual fund operating expenses (expenses you pay each year as a percentage of the value of your investment)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOthernanafalsefalseOperating Expenses Caption [Text]2falseRowprimaryElement*5false0rr_OperatingExpensesColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherus-types:textBlockItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseShare class0rr_OperatingExpensesColumnNametruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse3falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalseOthernanafalsefalseShare class3falseRowprimaryElement*6false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00290.0029falsefalsefalsetruefalse2truetruetrue0.00290.0029falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement fees0rr_ManagementFeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00290.0029falsefalsefalsetruefalse3truetruetrue0.00290.0029falsefalsefalsetruefalseOthernanafalsefalseManagement fees4falseRowprimaryElement*7false0rr_DistributionAndService12b1FeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruetrue00&nbsp;falsefalsefalsetruefalse2truetruetrue0.00250.0025falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureDistribution [and/or Service] (12b-1) Fees" include all distribution or other expenses incurred during the most recent fiscal year under a plan adopted pursuant to rule 12b-1 [17 CFR 270.12b-1]. Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00160.0016falsefalsefalsetruefalse2truetruetrue0.00160.0016falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00160.0016falsefalsefalsetruefalse3truetruetrue0.00160.0016falsefalsefalsetruefalseOthernanafalsefalseOther expenses6falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00450.0045falsefalsefalsetruefalse2truetruetrue0.00700.0070falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal annual fund operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00450.0045falsefalsefalsetruefalse3truetruetrue0.00700.0070falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses36Annual Fund Operating Expenses - Putnam VT Money Market Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]442false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]443false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. Your actual costs may be higher or lower.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThe Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 1 -Subsection example falsefalseExpense Example Narrative [Text Block]444false0rr_ExpenseExampleWithRedemptionTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/ExpenseExamplePutnamVTMoneyMarketFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003882_Member * row dei_LegalEntityAxis compact pvt822671_S000003882_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/ExpenseExamplePutnamVTMoneyMarketFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003882_Member * row dei_LegalEntityAxis compact pvt822671_S000003882_Member * ~&lt;/div&gt; </div>truehttp://putnam.com/role/ExpenseExamplePutnamVTMoneyMarketFundfalsefalse0200319 - Schedule - Expense Example - Putnam VT Money Market Fund {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_ExpenseExampleByYearColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalseOtherus-types:textBlockItemTypestringThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue4646falsefalsefalsetruefalse2truefalsetrue7272falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue144144falsefalsefalsetruefalse2truefalsetrue224224falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue252252falsefalsefalsetruefalse2truefalsetrue390390falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue567567falsefalsefalsetruefalse2truefalsetrue872872falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Money Market Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003882Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Money Market Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010859Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Money Market FundPutnam VT Money Market Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse2truefalsetrue4646falsefalsefalsetruefalse3truefalsetrue144144falsefalsefalsetruefalse4truefalsetrue252252falsefalsefalsetruefalse5truefalsetrue567567falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Money Market Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Money Market Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003882Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Money Market Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010860Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Money Market FundPutnam VT Money Market Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalse2truefalsetrue7272falsefalsefalsetruefalse3truefalsetrue224224falsefalsefalsetruefalse4truefalsetrue390390falsefalsefalsetruefalse5truefalsetrue872872falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Money Market Fund-Class IB Shares52Expense Example - Putnam VT Money Market Fund Putnam VT Money Market Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]445false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00InvestmentsfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]446false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in money market instruments that are high quality and have short-term maturities. We invest significantly in certificates of deposit, commercial paper (including asset-backed commercial paper), U.S. government debt and repurchase agreements, corporate obligations and bankers acceptances. We may consider, among other factors, credit, interest rate, and prepayment risks, as well as general market conditions, when deciding whether to buy or sell investments.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]447false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]448false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>The effects of inflation may erode the value of your investment over time. Although the fund seeks to preserve the value of your investment at $1.00 per share, deterioration in the credit quality of issuers whose securities the fund holds or an increase in interest rates may impair the value of your investment, and it is possible to lose money by investing in the fund. The values of money market investments usually rise and fall in response to changes in interest rates. Interest rate risk is generally lowest for investments with short maturities (a significant part of the fund&#8217;s investments). Although the fund only buys high quality investments, investments backed by a letter of credit have the risk that the provider of the letter of credit will not be able to fulfill its obligations to the issuer.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]449false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]450false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. The performance information does not reflect insurance-related charges or expenses. If it did, performance would be lower. Please remember that past performance is not necessarily an indication of future results.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalsePerformance Narrative [Text Block]451false0rr_BarChartHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual total returns for class IA sharesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart [Heading]452false0rr_BarChartTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTMoneyMarketFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003882_Member * row dei_LegalEntityAxis compact pvt822671_S000003882_Member * ~&lt;/div&gt; </div>falsefalseBarChart18.jpg<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTMoneyMarketFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003882_Member * row dei_LegalEntityAxis compact pvt822671_S000003882_Member * ~&lt;/div&gt; </div>falsehttp://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTMoneyMarketFundfalsefalse0200519 - Schedule - Annual Total Returns (Bar Chart) - Putnam VT Money Market Fundtruefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Money Market Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003882Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Money Market Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010859Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Money Market FundPutnam VT Money Market Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_AnnualReturn2001rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.03990.0399falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.03990.0399falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.01460.0146falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.01460.0146falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.00760.0076falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.00760.0076falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.00910.0091falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.00910.0091falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.02790.0279falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.02790.0279falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.04660.0466falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.04660.0466falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.05050.0505falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.05050.0505falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.02830.0283falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.02830.0283falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.00350.0035falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.00350.0035falsefalsefalsetruefalseOthernanafalsefalse200910falseRowprimaryElement*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.00030.0003falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.00030.0003falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) - Putnam VT Money Market Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]453false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>Year-to-date performance through 3/31/11</p><p>0.00%</p><p>Best calendar quarter Q1 01</p><p>1.37%</p><p>Worst calendar quarter Q4 10</p><p>0.00</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseBar Chart Closing [Text Block]454false0rr_AverageAnnualReturnCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Average annual total returns (<i>for periods ending 12/31/10</i>)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 5 -Subsection b falsefalseCaption455false0rr_PerformanceTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTMoneyMarketFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003882_Member * row dei_LegalEntityAxis compact pvt822671_S000003882_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTMoneyMarketFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003882_Member * row dei_LegalEntityAxis compact pvt822671_S000003882_Member * ~&lt;/div&gt; </div>truehttp://putnam.com/role/AverageAnnualTotalReturnsPutnamVTMoneyMarketFundfalsefalse0200619 - Schedule - Average Annual Total Returns - Putnam VT Money Market Fund {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_AverageAnnualReturnLabelrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruefalse00Lipper VP (Underlying Funds) Money Market Funds Category Averagefalsefalsefalsetruefalse2falsetruefalse00Class IAfalsefalsefalsetruefalse3falsetruefalse00Class IBfalsefalsefalsetruefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalseLabelfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_AverageAnnualReturnYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00010.0001falsefalsefalsetruefalse2truetruetrue0.00030.0003falsefalsefalsetruefalse3truetruetrue0.00030.0003falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_AverageAnnualReturnYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.02340.0234falsefalsefalsetruefalse2truetruetrue0.02560.0256falsefalsefalsetruefalse3truetruetrue0.02380.0238falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse5 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_AverageAnnualReturnYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.02110.0211falsefalsefalsetruefalse2truetruetrue0.02270.0227falsefalsefalsetruefalse3truetruetrue0.02050.0205falsefalsefalsetruefalseOtherxbrli:pureItemTypepureReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Money Market Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003882Memberdei_DocumentInformationDocumentAxisexplicitMembertruefalsePerformance Measurerr_PerformanceMeasureAxisrr_PerformanceMeasureDomainrr_PerformanceMeasureAxisexplicitMemberfalsefalsePutnam VT Money Market Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010859Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Money Market FundPerformance MeasurePutnam VT Money Market Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Class 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SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Class IBClass IBfalsefalsefalsetruefalse2truetruetrue0.00030.0003falsefalsefalsetruefalse3truetruetrue0.02380.0238falsefalsefalsetruefalse4truetruetrue0.02050.0205falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Money Market Fund-Class IB Shares3falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Money Market Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003882Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseLipper VP (Underlying Funds) Money Market Funds Category Averagerr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_LipperVPUnderlyingFundsMoneyMarketFundsCategoryAverageMemberrr_PerformanceMeasureAxisexplicitMembertruefalseShare Classesrr_ProspectusShareClassAxisrr_ShareClassDomainrr_ProspectusShareClassAxisexplicitMemberPutnam VT Money Market FundLipper VP (Underlying Funds) Money Market Funds Category AverageShare ClassesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Lipper VP (Underlying Funds) Money Market Funds Category AverageLipper VP (Underlying Funds) Money Market Funds Category Averagefalsefalsefalsetruefalse2truetruetrue0.00010.0001falsefalsefalsetruefalse3truetruetrue0.02340.0234falsefalsefalsetruefalse4truetruetrue0.02110.0211falsefalsefalsetruefalseOthernanafalsefalseLipper VP (Underlying Funds) Money Market Funds Category Average43Average Annual Total Returns - Putnam VT Money Market Fund Putnam VT Money Market FundUnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to PerformanceTableData.No authoritative reference available.falsefalsePerformance [Table]456false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://putnam.com/role/riskreturnsummary1falsefalsefalse00Putnam VT Multi-Cap Growth FundPutnam VT Multi-Cap Growth Fundfalsefalsefalsefalsefalse20falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Putnam VT Multi-Cap Growth Fund 5/1/2010 - 4/30/2011 TwelveMonthsEnded_30Apr2011_S000003884_Memberhttp://www.sec.gov/CIK0000822671duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsepvt822671_S000003884Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003884Memberdei_DocumentInformationDocumentAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0OthernaNo definition available.No authoritative reference available.falsefalsePutnam VT Multi-Cap Growth Fund458false0rr_RiskReturnHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PUTNAM VT MULTI-CAP GROWTH FUNDfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 falsefalseRisk/Return [Heading]459false0rr_ObjectiveHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00GoalfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]460false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT Multi-Cap Growth Fund seeks long-term capital appreciation.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]461false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and expensesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]462false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. The fees and expenses information does not reflect insurance-related charges or expenses borne by contract holders indirectly investing in the fund. If it did, expenses would be higher.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]463false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualFundOperatingExpensesPutnamVTMultiCapGrowthFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003884_Member * row dei_LegalEntityAxis compact pvt822671_S000003884_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ 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Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003884Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Multi-Cap Growth Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010864Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Multi-Cap Growth FundPutnam VT Multi-Cap Growth Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_OperatingExpensesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)falsefalsefalsetruefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]0rr_OperatingExpensesCaptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual fund operating expenses (<i>expenses you pay each year as a percentage of the value of your investment</i>)Annual fund operating expenses (expenses you pay each year as a percentage of the value of your investment)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOthernanafalsefalseOperating Expenses Caption [Text]2falseRowprimaryElement*5false0rr_OperatingExpensesColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class IBfalsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherus-types:textBlockItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseShare class0rr_OperatingExpensesColumnNametruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse3falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalseOthernanafalsefalseShare class3falseRowprimaryElement*6false0rr_ManagementFeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00560.0056falsefalsefalsetruefalse2truetruetrue0.00560.0056falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureManagement Fees include investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement fees0rr_ManagementFeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00560.0056falsefalsefalsetruefalse3truetruetrue0.00560.0056falsefalsefalsetruefalseOthernanafalsefalseManagement fees4falseRowprimaryElement*7false0rr_DistributionAndService12b1FeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruetrue00&nbsp;falsefalsefalsetruefalse2truetruetrue0.00250.0025falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureDistribution [and/or Service] (12b-1) Fees" include all distribution or other expenses incurred during the most recent fiscal year under a plan adopted pursuant to rule 12b-1 [17 CFR 270.12b-1]. Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00190.0019falsefalsefalsetruefalse2truetruetrue0.00190.0019falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00190.0019falsefalsefalsetruefalse3truetruetrue0.00190.0019falsefalsefalsetruefalseOthernanafalsefalseOther expenses6falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00750.0075falsefalsefalsetruefalse2truetruetrue0.01000.0100falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal annual fund operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00750.0075falsefalsefalsetruefalse3truetruetrue0.01000.0100falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses36Annual Fund Operating Expenses - Putnam VT Multi Cap Growth Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]464false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]465false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue7777falsefalsefalsetruefalse2truefalsetrue102102falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue240240falsefalsefalsetruefalse2truefalsetrue318318falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue417417falsefalsefalsetruefalse2truefalsetrue552552falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue930930falsefalsefalsetruefalse2truefalsetrue12271227falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Multi-Cap Growth Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003884Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Multi-Cap Growth Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010863Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Multi-Cap Growth FundPutnam VT Multi-Cap Growth Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse2truefalsetrue7777falsefalsefalsetruefalse3truefalsetrue240240falsefalsefalsetruefalse4truefalsetrue417417falsefalsefalsetruefalse5truefalsetrue930930falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Multi-Cap Growth Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Multi-Cap Growth Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003884Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Multi-Cap Growth Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010864Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Multi-Cap Growth FundPutnam VT Multi-Cap Growth Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalse2truefalsetrue102102falsefalsefalsetruefalse3truefalsetrue318318falsefalsefalsetruefalse4truefalsetrue552552falsefalsefalsetruefalse5truefalsetrue12271227falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Multi-Cap Growth Fund-Class IB Shares52Expense Example - Putnam VT Multi Cap Growth Fund Putnam VT Multi-Cap Growth Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]467false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio turnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]468false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund&#8217;s turnover rate in the most recent fiscal year was 86%.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]469false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00InvestmentsfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]470false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks of U.S. companies of any size, with a focus on growth stocks. Growth stocks are issued by companies whose earnings are expected to grow faster than those of similar firms, and whose business growth and other characteristics may lead to an increase in stock price. We may consider, among other factors, a company&#8217;s valuation, financial strength, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]471false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]472false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. These risks are generally greater for small and midsize companies. Growth stocks may be more susceptible to earnings disappointments, and the market may not favor growth-style investing.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]473false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]474false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. The performance information does not reflect insurance-related charges or expenses. If it did, performance would be lower. Please remember that past performance is not necessarily an indication of future results.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalsePerformance Narrative [Text Block]475false0rr_BarChartHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual total returns for class IA sharesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart [Heading]476false0rr_BarChartTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTMultiCapGrowthFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003884_Member * row dei_LegalEntityAxis compact pvt822671_S000003884_Member * ~&lt;/div&gt; </div>falsefalseBarChart19.jpg<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTMultiCapGrowthFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003884_Member * row dei_LegalEntityAxis compact pvt822671_S000003884_Member * ~&lt;/div&gt; </div>falsehttp://putnam.com/role/AnnualTotalReturnsBarChartPutnamVTMultiCapGrowthFundfalsefalse0200520 - Schedule - Annual Total Returns (Bar Chart) - Putnam VT Multi Cap Growth Fundtruefalsefalse1falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Multi-Cap Growth Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003884Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Multi-Cap Growth Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010863Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Multi-Cap Growth FundPutnam VT Multi-Cap Growth Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_AnnualReturn2001rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.2999-0.2999falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2999-0.2999falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.3029-0.3029falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.3029-0.3029falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.32790.3279falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.32790.3279falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.10500.1050falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.10500.1050falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.10320.1032falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.10320.1032falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.08820.0882falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.08820.0882falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.06020.0602falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.06020.0602falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.3862-0.3862falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.3862-0.3862falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.32480.3248falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20090rr_AnnualReturn2009truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.32480.3248falsefalsefalsetruefalseOthernanafalsefalse200910falseRowprimaryElement*13false0rr_AnnualReturn2010rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.19870.1987falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.19870.1987falsefalsefalsetruefalseOthernanafalsefalse2010110Annual Total Returns (Bar Chart) - Putnam VT Multi Cap Growth Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]477false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>Year-to-date performance through 3/31/11</p><p>6.10%</p><p>Best calendar quarter Q4 01</p><p>21.15%</p><p>Worst calendar quarter Q3 01</p><p>-29.40%</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalseBar Chart Closing [Text Block]478false0rr_AverageAnnualReturnCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Average annual total returns (<i>for periods ending 12/31/10</i>)falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 5 -Subsection b falsefalseCaption479false0rr_PerformanceTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTMultiCapGrowthFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003884_Member * row dei_LegalEntityAxis compact pvt822671_S000003884_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTMultiCapGrowthFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003884_Member * row dei_LegalEntityAxis compact pvt822671_S000003884_Member * ~&lt;/div&gt; </div>truehttp://putnam.com/role/AverageAnnualTotalReturnsPutnamVTMultiCapGrowthFundfalsefalse0200620 - Schedule - Average Annual Total Returns - Putnam VT Multi Cap Growth Fund {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_AverageAnnualReturnLabelrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruefalse00Russell 3000 Growth Indexfalsefalsefalsetruefalse2falsetruefalse00Class IAfalsefalsefalsetruefalse3falsetruefalse00Class IBfalsefalsefalsetruefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalseLabelfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_IndexNoDeductionForFeesExpensesTaxesrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00(no deduction for fees or expenses)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherxbrli:stringItemTypestringThe Performance Table includes a parenthetical, indicating that the Index "(reflects no deduction for fees, expenses or taxes)". 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Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]487false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. The fees and expenses information does not reflect insurance-related charges or expenses borne by contract holders indirectly investing in the fund. If it did, expenses would be higher.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. 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Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00280.0028falsefalsefalsetruefalse2truetruetrue0.00280.0028falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). 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If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. 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The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue8686falsefalsefalsetruefalse2truefalsetrue111111falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue268268falsefalsefalsetruefalse2truefalsetrue347347falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue466466falsefalsefalsetruefalse2truefalsetrue601601falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue10371037falsefalsefalsetruefalse2truefalsetrue13321332falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]495false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks of U.S. companies of any size, with a focus on value stocks. Value stocks are issued by companies that we believe are currently undervalued by the market. If we are correct and other investors recognize the value of the company, the price of its stock may rise. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]496false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]497false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20100rr_AnnualReturn2010truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.24320.2432falsefalsefalsetruefalseOthernanafalsefalse201017Annual Total Returns (Bar Chart) - Putnam VT Multi Cap Value Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to BarChartData.No authoritative reference available.falsefalseBar Chart [Table]502false0rr_BarChartClosingTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>Year-to-date performance through 3/31/11</p><p>5.48%</p><p>Best calendar quarter Q2 09</p><p>24.85%</p><p>Worst calendar quarter Q4 08</p><p>-26.41%</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. 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If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 5 -Subsection b falsefalseCaption504false0rr_PerformanceTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTMultiCapValueFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003881_Member * row dei_LegalEntityAxis compact pvt822671_S000003881_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AverageAnnualTotalReturnsPutnamVTMultiCapValueFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003881_Member * row dei_LegalEntityAxis compact pvt822671_S000003881_Member * ~&lt;/div&gt; </div>truehttp://putnam.com/role/AverageAnnualTotalReturnsPutnamVTMultiCapValueFundfalsefalse0200621 - Schedule - Average Annual Total Returns - Putnam VT Multi Cap Value Fund {Transposed}truefalsefalse1falseColumnprimaryElement*4false0rr_AverageAnnualReturnLabelrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruefalse00Russell 3000 Value Indexfalsefalsefalsetruefalse2falsetruefalse00Class IAfalsefalsefalsetruefalse3falsetruefalse00Class IBfalsefalsefalsetruefalseOtherxbrli:stringItemTypestringThis item represents Average Anuual Total Returns. If a Multiple Class Fund offers a Class in the prospectus that converts into another Class after a stated period, compute average annual total returns in the table by using the returns of the other Class for the period after conversion.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iii -Clause 1 -Exhibit 2 -Subsection b falsefalseLabelfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_IndexNoDeductionForFeesExpensesTaxesrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00(no deduction for fees or expenses)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalseOtherxbrli:stringItemTypestringThe Performance Table includes a parenthetical, indicating that the Index "(reflects no deduction for fees, expenses or taxes)". 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inceptionfalseUSDfalsefalse$6falseColumnprimaryElement*9false0rr_AverageAnnualReturnInceptionDaterrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse002003-05-01falsefalsetruetruefalse2falsetruefalse002003-05-01falsefalsetruetruefalse3falsetruefalse002003-05-01falsefalsetruetruefalseOtherxbrli:dateItemTypedateReturn Before Taxes.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 4 -Subsection b falsefalseInception DatefalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Multi-Cap Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003881Memberdei_DocumentInformationDocumentAxisexplicitMembertruefalsePerformance Measurerr_PerformanceMeasureAxisrr_PerformanceMeasureDomainrr_PerformanceMeasureAxisexplicitMemberfalsefalsePutnam VT Multi-Cap Value Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010857Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Multi-Cap Value FundPerformance MeasurePutnam VT Multi-Cap Value Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Class IAClass IAfalsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3truetruetrue0.24320.2432falsefalsefalsetruefalse4truetruetrue0.03150.0315falsefalsefalsetruefalse5truetruetrue0.09210.0921falsefalsefalsetruefalse6falsetruefalse002003-05-012003-05-01falsefalsetruetruefalseOthernanafalsefalsePutnam VT Multi-Cap Value Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Multi-Cap Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003881Memberdei_DocumentInformationDocumentAxisexplicitMembertruefalsePerformance Measurerr_PerformanceMeasureAxisrr_PerformanceMeasureDomainrr_PerformanceMeasureAxisexplicitMemberfalsefalsePutnam VT Multi-Cap Value Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010858Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Multi-Cap Value FundPerformance MeasurePutnam VT Multi-Cap Value Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Class IBClass IBfalsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3truetruetrue0.24060.2406falsefalsefalsetruefalse4truetruetrue0.02900.0290falsefalsefalsetruefalse5truetruetrue0.08950.0895falsefalsefalsetruefalse6falsetruefalse002003-05-012003-05-01falsefalsetruetruefalseOthernanafalsefalsePutnam VT Multi-Cap Value Fund-Class IB Shares3falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Multi-Cap Value Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003881Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseRussell 3000 Value Indexrr_PerformanceMeasureAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_RussellThreeThousandValueIndexMemberrr_PerformanceMeasureAxisexplicitMembertruefalseShare Classesrr_ProspectusShareClassAxisrr_ShareClassDomainrr_ProspectusShareClassAxisexplicitMemberPutnam VT Multi-Cap Value FundRussell 3000 Value IndexShare ClassesStandard00truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsetruefalse00Russell 3000 Value IndexRussell 3000 Value Indexfalsefalsefalsetruefalse2falsefalsefalse00(no deduction for fees or expenses)(no deduction for fees or expenses)falsefalsefalsetruefalse3truetruetrue0.16230.1623falsefalsefalsetruefalse4truetruetrue0.01450.0145falsefalsefalsetruefalse5truetruetrue0.07170.0717falsefalsefalsetruefalse6falsetruefalse002003-05-012003-05-01falsefalsetruetruefalseOthernanafalsefalseRussell 3000 Value Index63Average Annual Total Returns - Putnam VT Multi Cap Value Fund Putnam VT Multi-Cap Value FundUnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_PerformanceMeasureAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to PerformanceTableData.No authoritative reference available.falsefalsePerformance [Table]505false0rr_PerformanceTableNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund&#8217;s performance is compared to the Russell 3000 Value Index, an index of those companies in the broad-market Russell 3000 Index chosen for their value orientation. As of September 1, 2010, the Russell 3000 Value Index replaced the Russell Midcap Value Index as the benchmark for this fund because of a change in the fund&#8217;s investment strategy. The one-year, five-year and since-inception returns for the Russell Midcap Value Index for the periods ending December 31, 2010 were 24.75%, 4.08% and 11.32%, respectively.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringIf the Fund has annual returns for at least one calendar year, provide a table showing the Fund's (A) average annual total return; (B) average annual total return (after taxes on distributions); and (C) average annual total return (after taxes on distributions and redemption). A Money Market Fund should show only the returns described in clause (A) of the preceding sentence. All returns should be shown for 1-, 5-, and 10- calendar year periods ending on the date of the most recently completed calendar year (or for the life of the Fund, if shorter), but only for periods subsequent to the effective date of the Fund's registration statement. The table also shouldshow the returns of an appropriate broadbased securities market index as defined in Instruction 5 to Item 22(b)(7) for the same periods. A Fund that has been in existence for more than 10 years also may include returns for the life of the Fund. A Money Market Fund may provide the Fund's 7-day yield ending on the date of the most recent calendar year or disclose a toll-free (or collect) telephone number that investors can use to obtain the Fund's current 7-day yield. For a Fund (other than a Money Market Fund or a Fund described in General Instruction C.3.(d)(iii)), provide the information in the following table with the specified captions AVERAGE ANNUAL TOTAL RETURNS (For the periods ended December 31, _____). For a Fund that provides annual total returns for only one calendar year or for a Fund that does not include the bar chart because it does not have annual returns for a full calendar year, modify, as appropriate, the narrative explanation required by paragraph (c)(2)(i) (e.g., by stating that the information gives some indication of the risks of an investment in the Fund by comparing the Fund's performance with a broad measure of market performance).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph iv -Subsection b falsefalsePerformance Table Narrative506false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://putnam.com/role/riskreturnsummary1falsefalsefalse00Putnam VT Research FundPutnam VT Research Fundfalsefalsefalsefalsefalse22falsefalsetruefalse{dei_DocumentInformationDocumentAxis} : Putnam VT Research Fund 5/1/2010 - 4/30/2011 TwelveMonthsEnded_30Apr2011_S000003887_Memberhttp://www.sec.gov/CIK0000822671duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsepvt822671_S000003887Memberdei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003887Memberdei_DocumentInformationDocumentAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0OthernaNo definition available.No authoritative reference available.falsefalsePutnam VT Research Fund508false0rr_RiskReturnHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PUTNAM VT RESEARCH FUNDfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 falsefalseRisk/Return [Heading]509false0rr_ObjectiveHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00GoalfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective [Heading]510false0rr_ObjectivePrimaryTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Putnam VT Research Fund seeks capital appreciation.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringInvestment Objectives/Goals. Disclose the Fund's investment objectives or goals. A Fund also may identify its type or category (e.g., that it is a Money Market Fund or a balanced fund).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 -Subsection a falsefalseObjective, Primary [Text Block]511false0rr_ExpenseHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Fees and expensesfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Summary Fee Table Includes the following information, in plain English under rule 421(d) under the Securities Act, after Item 2 Fees and expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. The following Instructions apply to New Funds.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph d -Subsection instructions falsefalseExpense [Heading]512false0rr_ExpenseNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following table describes the fees and expenses you may pay if you buy and hold shares of the fund. The fees and expenses information does not reflect insurance-related charges or expenses borne by contract holders indirectly investing in the fund. If it did, expenses would be higher.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringThis table describes the fees and expenses that you may pay if you buy and hold shared 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 $[_____] in [name of fund family] funds. Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. Modify the narrative explanation to state that Fund shares are sold on a national securities exchange at the end of the time periods indicated, and that brokerage commissions for buying and selling Fund shares through a broker are not reflected.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph b -Subsection instructions falsefalseExpense Narrative [Text Block]513false0rr_AnnualFundOperatingExpensesTableTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<div> &lt;div style="display:none;"&gt;~ http://putnam.com/role/AnnualFundOperatingExpensesPutnamVTResearchFund column period compact * column rr_ProspectusShareClassAxis compact * row primary compact * row dei_DocumentInformationDocumentAxis compact pvt822671_S000003887_Member * row dei_LegalEntityAxis compact pvt822671_S000003887_Member * ~&lt;/div&gt; </div>falsefalse<div> &lt;div style="display:none;"&gt;~ 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ClassesStandard0falseUSDfalsefalse$2falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Research Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003887Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Research Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010869Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Research FundPutnam VT Research Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$3falseColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Research Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003887Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Research Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010870Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Research FundPutnam VT Research Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170falseUSDfalsefalse$1falseRowprimaryElement*4false0rr_OperatingExpensesCaptionrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00Annual fund operating expenses (<I>expenses you pay each year as a percentage of the value of your investment</I>)falsefalsefalsetruefalseOtherxbrli:stringItemTypestringAnnual Fund Operating Expenses (ongoing expenses that you pay each year as a percentage of the value of your investment)Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 7 -Subsection table falsefalseOperating Expenses Caption [Text]0rr_OperatingExpensesCaptiontruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Annual fund operating expenses (<I>expenses you pay each year as a percentage of the value of your investment</I>)Annual fund operating expenses (expenses you pay each year as a percentage of the value of your investment)falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalsefalse00falsefalsefalsefalsefalseOthernanafalsefalseOperating Expenses Caption [Text]2falseRowprimaryElement*5false0rr_OperatingExpensesColumnNamerrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00Class IAfalsefalsefalsetruefalse2falsefalsefalse00Class 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investment advisory fees (including any fees based on the Fund's performance), any other management fees payable to the investment adviser or its affiliates, and administrative fees payable to the investment adviser or its affiliates that are not included as "Other Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph a -Subsection instructions falsefalseManagement fees0rr_ManagementFeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00560.0056falsefalsefalsetruefalse3truetruetrue0.00560.0056falsefalsefalsetruefalseOthernanafalsefalseManagement fees4falseRowprimaryElement*7false0rr_DistributionAndService12b1FeesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsetruetrue00&nbsp;falsefalsefalsetruefalse2truetruetrue0.00250.0025falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureDistribution [and/or Service] (12b-1) Fees" include all distribution or other expenses incurred during the most recent fiscal year under a plan adopted pursuant to rule 12b-1 [17 CFR 270.12b-1]. Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00250.0025falsefalsefalsetruefalse2truetruetrue0.00250.0025falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. The amount of expenses deducted from the Fund's assets are the amounts shown as expenses in the Fund's statement of operations (including increases resulting from complying with paragraph 2(g) of rule 6-07 of Regulation S-X [17 CFR 210.6-07]). "Other Expenses" do not include extraordinary expenses as determined under generally accepted accounting principles (see Accounting Principles Board Opinion No. 30). If extraordinary expenses were incurred that materially affected the Fund's "Other Expenses," disclose in a footnote to the table what "Other Expenses" would have been had the extraordinary expenses been included.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph c -Clause i -Subsection instructions falsefalseOther expenses0rr_OtherExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00250.0025falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseOther expenses6falseRowprimaryElement*9false0rr_ExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00810.0081falsefalsefalsetruefalse2truetruetrue0.01060.0106falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4TypepureTotal Annual Fund Operating Expenses. If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. If the Fund has changed its fiscal year and, as a result, the most recent fiscal year is less than three months, use the fiscal year prior to the most recent fiscal year as the basis for determining "Annual Fund Operating Expenses."Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subparagraph d -Subsection instructions falsefalseTotal annual fund operating expenses0rr_ExpensesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2truetruetrue0.00810.0081falsefalsefalsetruefalse3truetruetrue0.01060.0106falsefalsefalsetruefalseOthernanafalsefalseTotal annual fund operating expenses36Annual Fund Operating Expenses - Putnam VT Research Fund UnKnownUnKnownUnKnownUnKnownfalsetrueColumnperiodPeriod*Columndei_DocumentInformationDocumentAxisAxis*Columnrr_ProspectusShareClassAxisAxis*ColumnunitUnit*RowprimaryElement*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to OperatingExpensesData.No authoritative reference available.falsefalseAnnual Fund Operating Expenses [Table]514false0rr_ExpenseExampleHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00ExamplefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringHeading for Expense Example.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalseExpense Example [Heading]515false0rr_ExpenseExampleNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The following hypothetical example is intended to help you compare the cost of investing in the fund with the cost of investing in other funds. The example does not reflect insurance-related charges or expenses. If it did, expenses would be higher. It assumes that you invest $10,000 in the fund for the time periods indicated and then redeem or hold all your shares at the end of those periods. It assumes a 5% return on your investment each year and that the fund&#8217;s operating expenses remain the same. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue8383falsefalsefalsetruefalse2truefalsetrue108108falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue259259falsefalsefalsetruefalse2truefalsetrue337337falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue450450falsefalsefalsetruefalse2truefalsetrue585585falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue10021002falsefalsefalsetruefalse2truefalsetrue12971297falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse10 yearsfalseUSDfalsefalse$1falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Research Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003887Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Research Fund-Class IA Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010869Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Research FundPutnam VT Research Fund-Class IA SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IAClass IAfalsefalsefalsetruefalse2truefalsetrue8383falsefalsefalsetruefalse3truefalsetrue259259falsefalsefalsetruefalse4truefalsetrue450450falsefalsefalsetruefalse5truefalsetrue10021002falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Research Fund-Class IA Shares2falseRowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*duration2010-05-01T00:00:002011-04-30T00:00:00falsefalsePutnam VT Research Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_S000003887Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalsePutnam VT Research Fund-Class IB Sharesrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldipvt822671_C000010870Memberrr_ProspectusShareClassAxisexplicitMemberPutnam VT Research FundPutnam VT Research Fund-Class IB SharesUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso421700truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Class IBClass IBfalsefalsefalsetruefalse2truefalsetrue108108falsefalsefalsetruefalse3truefalsetrue337337falsefalsefalsetruefalse4truefalsetrue585585falsefalsefalsetruefalse5truefalsetrue12971297falsefalsefalsetruefalseOthernanafalsefalsePutnam VT Research Fund-Class IB Shares52Expense Example - Putnam VT Research Fund Putnam VT Research Fund (USD $)UnKnownUnKnownUnKnownUnKnownfalsetrueColumnprimaryElement*RowperiodPeriod*Rowdei_DocumentInformationDocumentAxisAxis*Rowrr_ProspectusShareClassAxisAxis*RowunitUnit*falsefalsefalseOtherus-types:textBlockItemTypestringContains a command for the SEC Viewer for the role corresponding to ExpenseExample.No authoritative reference available.falsefalseExpense Example, With Redemption [Table]517false0rr_PortfolioTurnoverHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00Portfolio turnoverfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]518false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. The fund&#8217;s turnover rate in the most recent fiscal year was 100%.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringDisclose the portfolio turnover rate provided in response to Item 14(a) for the most recent fiscal year (or for such shorter period as the Fund has been in operation). Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 3 -Subsection example falsefalsePortfolio Turnover [Text Block]519false0rr_StrategyHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00InvestmentsfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]520false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks (growth or value stocks or both) of large U.S. companies that we believe have favorable investment potential. For example, we may purchase stocks of companies with stock prices that reflect a value lower than that which we place on the company. We may also consider other factors we believe will cause the stock price to rise. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]521false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]522false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. Growth stocks may be more susceptible to earnings disappointments, and value stocks may fail to rebound.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]523false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]524false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. The performance information does not reflect insurance-related charges or expenses. If it did, performance would be lower. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.1862-0.1862falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.2206-0.2206falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.2206-0.2206falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.25690.2569falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.25690.2569falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.07790.0779falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.07790.0779falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.05260.0526falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20050rr_AnnualReturn2005truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.05260.0526falsefalsefalsetruefalseOthernanafalsefalse20056falseRowprimaryElement*9false0rr_AnnualReturn2006rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.11630.1163falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20060rr_AnnualReturn2006truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.11630.1163falsefalsefalsetruefalseOthernanafalsefalse20067falseRowprimaryElement*10false0rr_AnnualReturn2007rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.00830.0083falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20070rr_AnnualReturn2007truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.00830.0083falsefalsefalsetruefalseOthernanafalsefalse20078falseRowprimaryElement*11false0rr_AnnualReturn2008rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.3842-0.3842falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20080rr_AnnualReturn2008truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.3842-0.3842falsefalsefalsetruefalseOthernanafalsefalse20089falseRowprimaryElement*12false0rr_AnnualReturn2009rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.33540.3354falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. 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Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. 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If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue9393falsefalsefalsetruefalse2truefalsetrue118118falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue290290falsefalsefalsetruefalse2truefalsetrue368368falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue504504falsefalsefalsetruefalse2truefalsetrue638638falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue11201120falsefalsefalsetruefalse2truefalsetrue14131413falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. 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Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]542false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]544false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks of small U.S. companies, with a focus on value stocks. Value stocks are issued by companies that we believe are currently undervalued by the market. If we are correct and other investors recognize the value of the company, the price of its stock may rise. We invest mainly in small companies of a size similar to those in the Russell 2000 Value index. As of March 31, 2011, the index was composed of companies having market capitalizations of between approximately $8 million and $4.94 billion. We may consider, among other factors, a company&#8217;s valuation, financial strength, growth potential, competitive position in its industry, projected future earnings, cash flows and dividends when deciding whether to buy or sell investments.falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringPrincipal investment strategies of the Fund. Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]545false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]546false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. These risks are generally greater for small and midsize companies. Value stocks may fail to rebound, and the market may not favor value-style investing.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. A Fund may, in responding to this Item, describe the types of investors for whom the Fund is intended or the types of investment goals that may be consistent with an investment in the Fund.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subparagraph i -Clause instruction -Subsection b falsefalseRisk Narrative [Text Block]547false0rr_BarChartAndPerformanceTableHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00PerformancefalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subsection b falsefalseBar Chart and Performance Table [Heading]548false0rr_PerformanceNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The performance information below gives some indication of the risks associated with an investment in the fund by showing the fund&#8217;s performance year to year and over time. The performance information does not reflect insurance-related charges or expenses. If it did, performance would be lower. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20010rr_AnnualReturn2001truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.18420.1842falsefalsefalsetruefalseOthernanafalsefalse20012falseRowprimaryElement*5false0rr_AnnualReturn2002rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse-0.1806-0.1806falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph ii -Subsection b falsefalse20020rr_AnnualReturn2002truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse-0.1806-0.1806falsefalsefalsetruefalseOthernanafalsefalse20023falseRowprimaryElement*6false0rr_AnnualReturn2003rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.50060.5006falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. 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The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20030rr_AnnualReturn2003truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.50060.5006falsefalsefalsetruefalseOthernanafalsefalse20034falseRowprimaryElement*7false0rr_AnnualReturn2004rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.26540.2654falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a -Subsection b falsefalse20040rr_AnnualReturn2004truefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1truetruefalse0.26540.2654falsefalsefalsetruefalseOthernanafalsefalse20045falseRowprimaryElement*8false0rr_AnnualReturn2005rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.07300.0730falsefalsefalsetruefalseOtherxbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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Shareholder Fees (fees paid directly from your investment) Example 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 you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be You would pay the following expenses if you did not redeem your shares The Example does not reflect sales charges (loads) on reinvested dividends [and other distributions]. If these sales charges (loads) were included, your costs would be higher. Portfolio Turnover 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. 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 __% of the average value of its whole portfolio. Instructions. A.3.instructions.6 New Funds. For purposes of this Item, a "New Fund" is a Fund that does not include in Form N-1A financial statements reporting operating results or that includes financial statements for the Fund's initial fiscal year reporting operating results for a period of 6 months or less. 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Include the narrative explanations in the order indicated. A Fund may modify the narrative explanations if the explanation contains comparable information to that shown.The narrative explanation regarding sales charge discounts is only required by a Fund that offers such discounts and should specify the minimum level of investment required to qualify for a discount. 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Under an appropriate caption or a subcaption of "Other Expenses," disclose the amount of any distribution or similar expenses deducted from the Fund's assets other than pursuant to a rule 12b-1 plan.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 9 -Subsection table falsefalseDistribution and service (12b-1) fees0rr_DistributionAndService12b1FeesOverAssetstruefalsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsetruetrue00&nbsp;&nbsp;falsefalsefalsetruefalse3truetruetrue0.00250.0025falsefalsefalsetruefalseOthernanafalsefalseDistribution and service (12b-1) fees5falseRowprimaryElement*8false0rr_OtherExpensesOverAssetsrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruetrue0.00160.0016falsefalsefalsetruefalse2truetruetrue0.00160.0016falsefalsefalsetruefalse3falsetruetrue00falsefalsefalsetruefalseOtherrr:NonNegativePure4Typepure"Other Expenses" include all expenses not otherwise disclosed in the table that are deducted from the Fund's assets or charged to all shareholder accounts. 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If the Fund is a Feeder Fund, reflect the aggregate expenses of the Feeder Fund and the Master Fund in a single fee table using the captions provided. In a footnote to the fee table, state that the table and Example reflect the expenses of both the Feeder and Master Funds. If the prospectus offers more than one Class of a Multiple Class Fund or more than one Feeder Fund that invests in the same Master Fund, provide a separate response for each Class or Feeder Fund. Base the percentages of "Annual Fund Operating Expenses" on amounts incurred during the Fund's most recent fiscal year, but include in expenses amounts that would have been incurred absent expense reimbursement or fee waiver arrangements. 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The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalseShare classfalseUSDfalsefalse$2falseColumnprimaryElement*5false0rr_ExpenseExampleYear01rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue7676falsefalsefalsetruefalse2truefalsetrue101101falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 4 -Subsection instructions falsefalse1 yearfalseUSDfalsefalse$3falseColumnprimaryElement*6false0rr_ExpenseExampleYear03rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue237237falsefalsefalsetruefalse2truefalsetrue315315falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse3 yearsfalseUSDfalsefalse$4falseColumnprimaryElement*7false0rr_ExpenseExampleYear05rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue411411falsefalsefalsetruefalse2truefalsetrue547547falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. Although your actual costs may be higher or lower.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 1 -Subparagraph 2 -Subsection example falsefalse5 yearsfalseUSDfalsefalse$5falseColumnprimaryElement*8false0rr_ExpenseExampleYear10rrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsetrue918918falsefalsefalsetruefalse2truefalsetrue12161216falsefalsefalsetruefalseMonetaryrr:NonNegativeMonetaryTypemonetaryThe Example assumes that you invest $10,000 in the Fund for the time periods indicated and then you redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return per year and that the Fund's operating expenses remained the same. 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Disclose the period for which the information is provided if less than a full fiscal year. A Fund that is a Money Market Fund may omit the portfolio turnover information required by this Item.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 3 -Paragraph 5 -Subsection instructions falsefalsePortfolio Turnover [Heading]566false0rr_PortfolioTurnoverTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00The fund pays transaction-related costs when it buys and sells securities (or &#8220;turns over&#8221; its portfolio). A higher turnover rate may indicate higher transaction costs. These costs, which are not reflected in annual fund operating expenses or the above example, affect fund performance. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy [Heading]568false0rr_StrategyNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00We invest mainly in common stocks of midsize and large U.S. companies, with a focus on growth stocks. Growth stocks are issued by companies whose earnings are expected to grow faster than those of similar firms, and whose business growth and other characteristics may lead to an increase in stock price. 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Summarize how the Fund intends to achieve its investment objectives by identifying the Fund's principal investment strategies (including the type or types of securities in which the Fund invests or will invest principally) and any policy to concentrate in securities of issuers in a particular industry or group of industries.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection a falsefalseStrategy Narrative [Text Block]569false0rr_RiskHeadingrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00RisksfalsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNarrative Risk Disclosure.Reference 1: 1 -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Paragraph 1 -Subsection b falsefalseRisk [Heading]570false0rr_RiskNarrativeTextBlockrrfalsenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00<p>It is important to understand that you can lose money by investing in the fund.</p><p>The prices of stocks in the fund&#8217;s portfolio may fall or fail to rise over extended periods of time for a variety of reasons, including both general financial market conditions and factors related to a specific company or industry. These risks are generally greater for midsize companies. Growth stocks may be more susceptible to earnings disappointments, and the market may not favor growth-style investing.</p><p>The fund may not achieve its goal, and it is not intended to be a complete investment program. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.</p>falsefalsefalsefalsefalseOtherus-types:textBlockItemTypestringNarrative Risk Disclosure. 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Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. 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