XML 11 R9.htm IDEA: XBRL DOCUMENT v2.4.0.6
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Document Type dei_DocumentType 485BPOS
Document Period End Date dei_DocumentPeriodEndDate Dec. 14, 2011
Registrant Name dei_EntityRegistrantName JANUS INVESTMENT FUND
Central Index Key dei_EntityCentralIndexKey 0000277751
Amendment Flag dei_AmendmentFlag false
Document Creation Date dei_DocumentCreationDate Dec. 14, 2011
Document Effective Date dei_DocumentEffectiveDate Dec. 15, 2011
Prospectus Date rr_ProspectusDate Dec. 15, 2011
Perkins Select Value Fund | Class A, C, S, I, T Shares
  
Risk/Return: rr_RiskReturnAbstract  
Risk/Return [Heading] rr_RiskReturnHeading FUND SUMMARY Perkins Select Value Fund
Objective [Heading] rr_ObjectiveHeading INVESTMENT OBJECTIVE
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock Perkins Select Value Fund seeks capital appreciation.
FEES AND EXPENSES OF THE FUND jif277751_FundFeesAndExpensesAbstract  
Expense [Heading] rr_ExpenseHeading FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block] rr_ExpenseNarrativeTextBlock This table describes the fees and expenses that you may pay if you buy and hold Shares of the Fund. Each share class has different expenses, but represents an investment in the same Fund.
Expense Breakpoint Discounts jif277751_ExpenseBreakpointDiscountsAbstract  
Expense Breakpoint Discounts [Text] rr_ExpenseBreakpointDiscounts For Class A Shares, you may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $50,000 in the Fund or in other Janus mutual funds. More information about these and other discounts, as well as eligibility requirements for each share class, is available from your financial professional and in the “Purchases” section on page 25 of the Fund’s Prospectus and in the “Purchases” section on page 55 of the Fund’s Statement of Additional Information.
Expense Breakpoint, Minimum Investment Required [Amount] rr_ExpenseBreakpointMinimumInvestmentRequiredAmount 50,000
SHAREHOLDER FEES rr_ShareholderFeesAbstract  
Shareholder Fees Caption [Text] rr_ShareholderFeesCaption SHAREHOLDER FEES (fees paid directly from your investment)
ANNUAL FUND OPERATING EXPENSES rr_OperatingExpensesAbstract  
Operating Expenses Caption [Text] rr_OperatingExpensesCaption ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Other Expenses, New Fund, Based on Estimates [Text] rr_OtherExpensesNewFundBasedOnEstimates Since the Fund is new, Other Expenses are based on the estimated expenses that the Fund expects to incur in its initial fiscal period.
Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination November 1, 2013
EXAMPLE: rr_ExpenseExampleAbstract  
Expense Example [Heading] rr_ExpenseExampleHeading EXAMPLE:
Expense Example Narrative [Text Block] rr_ExpenseExampleNarrativeTextBlock The following Example is based on expenses without waivers. The Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.
Expense Example by Year [Heading] rr_ExpenseExampleByYearHeading The Example assumes that you invest $10,000 in the Fund for the time periods indicated and reinvest all dividends and distributions. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses without waivers remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Expense Example by, Year, Caption [Text] rr_ExpenseExampleByYearCaption If Shares are redeemed:
Expense Example, No Redemption: rr_ExpenseExampleNoRedemptionAbstract  
Expense Example, No Redemption, By Year, Caption [Text] rr_ExpenseExampleNoRedemptionByYearCaption If Shares are not redeemed:
Portfolio Turnover: jif277751_PortfolioTurnoverAltAbstract  
Portfolio Turnover [Heading] rr_PortfolioTurnoverHeading Portfolio Turnover:
Portfolio Turnover [Text Block] rr_PortfolioTurnoverTextBlock The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund’s performance.
Principal Investment Strategies jif277751_PrincipalInvestmentStrategiesAbstract  
Strategy [Heading] rr_StrategyHeading PRINCIPAL INVESTMENT STRATEGIES
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock

The Fund pursues its investment objective by investing primarily in common stocks selected for their capital appreciation potential. The Fund primarily invests in the common stocks of companies of any size whose stock prices the portfolio managers believe to be undervalued. The Fund may also invest in foreign equity and debt securities, which may include investments in emerging markets.

The Fund focuses on companies that have fallen out of favor with the market or that appear to be temporarily misunderstood by the investment community. The Fund’s portfolio managers generally look for companies with:

• strong balance sheets and solid recurring free cash flows

• attractive relative and absolute valuation ratios or that have underperformed recently

• favorable reward to risk characteristics

The Fund may invest its assets in derivatives, which are instruments that have a value derived from or directly linked to an underlying asset, such as equity securities, bonds, commodities, currencies, interest rates, or market indices, as substitutes for securities in which the Fund invests. The Fund may invest in derivative instruments (by taking long and/or short positions) for different purposes, including hedging (to offset risks associated with an investment, currency exposure, or market conditions) and to earn income and enhance returns. For more information on the Fund’s use of derivatives, refer to the Fund’s shareholder reports and Form N-Q reports, which are filed with the Securities and Exchange Commission, when available.
Principal Investment Risks jif277751_PrincipalInvestmentRisksAbstract  
Risk [Heading] rr_RiskHeading PRINCIPAL INVESTMENT RISKS
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock

The biggest risk is that the Fund’s returns will vary, and you could lose money. The Fund is designed for long-term investors seeking an equity portfolio, including common stocks. Common stocks tend to be more volatile than many other investment choices.

Value Investing Risk. Because different types of stocks tend to shift in and out of favor depending on market and economic conditions, “value” stocks may perform differently than other types of stocks and from the market as a whole, and can continue to be undervalued by the market for long periods of time. It is also possible that a value stock will never appreciate to the extent expected.

Market Risk. The value of the Fund’s portfolio may decrease if the value of an individual company or security, or multiple companies or securities, in the portfolio decreases or if the portfolio managers’ belief about a company’s intrinsic worth is incorrect. Further, regardless of how well individual companies or securities perform, the value of the Fund’s portfolio could also decrease if there are deteriorating economic or market conditions. It is important to understand that the value of your investment may fall, sometimes sharply, in response to changes in the market, and you could lose money.

Foreign Exposure Risk. The Fund may have exposure to foreign markets, including emerging markets, which can be more volatile than the U.S. markets. As a result, its returns and net asset value may be affected to a large degree by fluctuations in currency exchange rates or political or economic conditions in a particular country. In some foreign markets, there may not be protection against failure by other parties to complete transactions. It may not be possible for the Fund to repatriate capital, dividends, interest, and other income from a particular country or governmental entity. In addition, a market swing in one or more countries or regions where the Fund has invested a significant amount of its assets may have a greater effect on the Fund’s performance than it would in a more geographically diversified portfolio. The Fund’s investments in emerging market countries may involve risks greater than, or in addition to, the risks of investing in more developed countries.

Derivatives Risk. Derivatives can be highly volatile and involve risks in addition to the risks of the underlying referenced securities. Gains or losses from a derivative can be substantially greater than the derivative’s original cost, and can therefore involve leverage. Derivatives can be less liquid than other types of investments and entail the risk that the counterparty will default on its payment obligations.

An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Risk Lose Money [Text] rr_RiskLoseMoney The biggest risk is that the Fund’s returns will vary, and you could lose money.
Risk Not Insured Depository Institution [Text] rr_RiskNotInsuredDepositoryInstitution An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
PERFORMANCE INFORMATION jif277751_FundPastPerformanceAbstract  
Bar Chart and Performance Table [Heading] rr_BarChartAndPerformanceTableHeading PERFORMANCE INFORMATION
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock The Fund does not have a full calendar year of operations. Performance information for certain periods will be included in the Fund’s first annual and/or semiannual report.
Performance One Year or Less [Text] rr_PerformanceOneYearOrLess The Fund does not have a full calendar year of operations.
Perkins Select Value Fund | Class A, C, S, I, T Shares | Class A
  
SHAREHOLDER FEES rr_ShareholderFeesAbstract  
Shareholder Fees Column [Text] rr_ShareholderFeesColumnName Class A
Maximum Sales Charge (load) Imposed on Purchases (as a percentage of offering price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice 5.75%
Maximum Deferred Sales Charge (load) (as a percentage of the lower of original purchase price or redemption proceeds) rr_MaximumDeferredSalesChargeOverOther none
ANNUAL FUND OPERATING EXPENSES rr_OperatingExpensesAbstract  
Operating Expenses Column [Text] rr_OperatingExpensesColumnName Class A
Management Fees (may adjust up or down) rr_ManagementFeesOverAssets 0.70%
Distribution/Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other Expenses rr_OtherExpensesOverAssets 0.48% [1]
Total Annual Fund Operating Expenses rr_ExpensesOverAssets 1.43% [2]
Fee Waiver rr_FeeWaiverOrReimbursementOverAssets 0.17% [2]
Net Annual Fund Operating Expenses After Fee Waiver rr_NetExpensesOverAssets 1.26% [2]
EXAMPLE: rr_ExpenseExampleAbstract  
Expense Example, By Year, Column [Text] rr_ExpenseExampleByYearColumnName Class A Shares
1 Year rr_ExpenseExampleYear01 712
3 Years rr_ExpenseExampleYear03 1,001
Expense Example, No Redemption: rr_ExpenseExampleNoRedemptionAbstract  
Expense Example, No Redemption, By Year, Column [Text] rr_ExpenseExampleNoRedemptionByYearColumnName Class A Shares
1 Year rr_ExpenseExampleNoRedemptionYear01 712
3 Years rr_ExpenseExampleNoRedemptionYear03 1,001
Perkins Select Value Fund | Class A, C, S, I, T Shares | Class C
  
SHAREHOLDER FEES rr_ShareholderFeesAbstract  
Shareholder Fees Column [Text] rr_ShareholderFeesColumnName Class C
Maximum Sales Charge (load) Imposed on Purchases (as a percentage of offering price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (load) (as a percentage of the lower of original purchase price or redemption proceeds) rr_MaximumDeferredSalesChargeOverOther 1.00%
ANNUAL FUND OPERATING EXPENSES rr_OperatingExpensesAbstract  
Operating Expenses Column [Text] rr_OperatingExpensesColumnName Class C
Management Fees (may adjust up or down) rr_ManagementFeesOverAssets 0.70%
Distribution/Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 1.00%
Other Expenses rr_OtherExpensesOverAssets 0.50% [1]
Total Annual Fund Operating Expenses rr_ExpensesOverAssets 2.20% [2]
Fee Waiver rr_FeeWaiverOrReimbursementOverAssets 0.19% [2]
Net Annual Fund Operating Expenses After Fee Waiver rr_NetExpensesOverAssets 2.01% [2]
EXAMPLE: rr_ExpenseExampleAbstract  
Expense Example, By Year, Column [Text] rr_ExpenseExampleByYearColumnName Class C Shares
1 Year rr_ExpenseExampleYear01 323
3 Years rr_ExpenseExampleYear03 688
Expense Example, No Redemption: rr_ExpenseExampleNoRedemptionAbstract  
Expense Example, No Redemption, By Year, Column [Text] rr_ExpenseExampleNoRedemptionByYearColumnName Class C Shares
1 Year rr_ExpenseExampleNoRedemptionYear01 223
3 Years rr_ExpenseExampleNoRedemptionYear03 688
Perkins Select Value Fund | Class A, C, S, I, T Shares | Class S
  
SHAREHOLDER FEES rr_ShareholderFeesAbstract  
Shareholder Fees Column [Text] rr_ShareholderFeesColumnName Class S
Maximum Sales Charge (load) Imposed on Purchases (as a percentage of offering price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (load) (as a percentage of the lower of original purchase price or redemption proceeds) rr_MaximumDeferredSalesChargeOverOther none
ANNUAL FUND OPERATING EXPENSES rr_OperatingExpensesAbstract  
Operating Expenses Column [Text] rr_OperatingExpensesColumnName Class S
Management Fees (may adjust up or down) rr_ManagementFeesOverAssets 0.70%
Distribution/Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other Expenses rr_OtherExpensesOverAssets 0.63% [1]
Total Annual Fund Operating Expenses rr_ExpensesOverAssets 1.58% [2]
Fee Waiver rr_FeeWaiverOrReimbursementOverAssets 0.07% [2]
Net Annual Fund Operating Expenses After Fee Waiver rr_NetExpensesOverAssets 1.51% [2]
EXAMPLE: rr_ExpenseExampleAbstract  
Expense Example, By Year, Column [Text] rr_ExpenseExampleByYearColumnName Class S Shares
1 Year rr_ExpenseExampleYear01 161
3 Years rr_ExpenseExampleYear03 499
Expense Example, No Redemption: rr_ExpenseExampleNoRedemptionAbstract  
Expense Example, No Redemption, By Year, Column [Text] rr_ExpenseExampleNoRedemptionByYearColumnName Class S Shares
1 Year rr_ExpenseExampleNoRedemptionYear01 161
3 Years rr_ExpenseExampleNoRedemptionYear03 499
Perkins Select Value Fund | Class A, C, S, I, T Shares | Class I
  
SHAREHOLDER FEES rr_ShareholderFeesAbstract  
Shareholder Fees Column [Text] rr_ShareholderFeesColumnName Class I
Maximum Sales Charge (load) Imposed on Purchases (as a percentage of offering price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (load) (as a percentage of the lower of original purchase price or redemption proceeds) rr_MaximumDeferredSalesChargeOverOther none
ANNUAL FUND OPERATING EXPENSES rr_OperatingExpensesAbstract  
Operating Expenses Column [Text] rr_OperatingExpensesColumnName Class I
Management Fees (may adjust up or down) rr_ManagementFeesOverAssets 0.70%
Distribution/Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses rr_OtherExpensesOverAssets 0.45% [1]
Total Annual Fund Operating Expenses rr_ExpensesOverAssets 1.15% [2]
Fee Waiver rr_FeeWaiverOrReimbursementOverAssets 0.14% [2]
Net Annual Fund Operating Expenses After Fee Waiver rr_NetExpensesOverAssets 1.01% [2]
EXAMPLE: rr_ExpenseExampleAbstract  
Expense Example, By Year, Column [Text] rr_ExpenseExampleByYearColumnName Class I Shares
1 Year rr_ExpenseExampleYear01 117
3 Years rr_ExpenseExampleYear03 365
Expense Example, No Redemption: rr_ExpenseExampleNoRedemptionAbstract  
Expense Example, No Redemption, By Year, Column [Text] rr_ExpenseExampleNoRedemptionByYearColumnName Class I Shares
1 Year rr_ExpenseExampleNoRedemptionYear01 117
3 Years rr_ExpenseExampleNoRedemptionYear03 365
Perkins Select Value Fund | Class A, C, S, I, T Shares | Class T
  
SHAREHOLDER FEES rr_ShareholderFeesAbstract  
Shareholder Fees Column [Text] rr_ShareholderFeesColumnName Class T
Maximum Sales Charge (load) Imposed on Purchases (as a percentage of offering price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (load) (as a percentage of the lower of original purchase price or redemption proceeds) rr_MaximumDeferredSalesChargeOverOther none
ANNUAL FUND OPERATING EXPENSES rr_OperatingExpensesAbstract  
Operating Expenses Column [Text] rr_OperatingExpensesColumnName Class T
Management Fees (may adjust up or down) rr_ManagementFeesOverAssets 0.70%
Distribution/Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses rr_OtherExpensesOverAssets 0.63% [1]
Total Annual Fund Operating Expenses rr_ExpensesOverAssets 1.33% [2]
Fee Waiver rr_FeeWaiverOrReimbursementOverAssets 0.07% [2]
Net Annual Fund Operating Expenses After Fee Waiver rr_NetExpensesOverAssets 1.26% [2]
EXAMPLE: rr_ExpenseExampleAbstract  
Expense Example, By Year, Column [Text] rr_ExpenseExampleByYearColumnName Class T Shares
1 Year rr_ExpenseExampleYear01 135
3 Years rr_ExpenseExampleYear03 421
Expense Example, No Redemption: rr_ExpenseExampleNoRedemptionAbstract  
Expense Example, No Redemption, By Year, Column [Text] rr_ExpenseExampleNoRedemptionByYearColumnName Class T Shares
1 Year rr_ExpenseExampleNoRedemptionYear01 135
3 Years rr_ExpenseExampleNoRedemptionYear03 421
Perkins Select Value Fund | Class D Shares
  
Risk/Return: rr_RiskReturnAbstract  
Risk/Return [Heading] rr_RiskReturnHeading FUND SUMMARY Perkins Select Value Fund
Objective [Heading] rr_ObjectiveHeading INVESTMENT OBJECTIVE
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock Perkins Select Value Fund seeks capital appreciation.
FEES AND EXPENSES OF THE FUND jif277751_FundFeesAndExpensesAbstract  
Expense [Heading] rr_ExpenseHeading FEES AND EXPENSES OF THE FUND
Expense Narrative [Text Block] rr_ExpenseNarrativeTextBlock This table describes the fees and expenses that you may pay if you buy and hold Shares of the Fund.
ANNUAL FUND OPERATING EXPENSES rr_OperatingExpensesAbstract  
Operating Expenses Caption [Text] rr_OperatingExpensesCaption ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Other Expenses, New Fund, Based on Estimates [Text] rr_OtherExpensesNewFundBasedOnEstimates Since the Fund is new, Other Expenses are based on the estimated expenses that the Fund expects to incur in its initial fiscal period.
Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination November 1, 2013
EXAMPLE: rr_ExpenseExampleAbstract  
Expense Example [Heading] rr_ExpenseExampleHeading EXAMPLE:
Expense Example Narrative [Text Block] rr_ExpenseExampleNarrativeTextBlock The following Example is based on expenses without waivers. The Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds.
Expense Example by Year [Heading] rr_ExpenseExampleByYearHeading The Example assumes that you invest $10,000 in the Fund for the time periods indicated, reinvest all dividends and distributions, and then redeem all of your Shares at the end of each period. The Example also assumes that your investment has a 5% return each year and that the Fund’s operating expenses without waivers remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Portfolio Turnover: jif277751_PortfolioTurnoverAltAbstract  
Portfolio Turnover [Heading] rr_PortfolioTurnoverHeading Portfolio Turnover:
Portfolio Turnover [Text Block] rr_PortfolioTurnoverTextBlock The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund’s performance.
Principal Investment Strategies jif277751_PrincipalInvestmentStrategiesAbstract  
Strategy [Heading] rr_StrategyHeading PRINCIPAL INVESTMENT STRATEGIES
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock

The Fund pursues its investment objective by investing primarily in common stocks selected for their capital appreciation potential. The Fund primarily invests in the common stocks of companies of any size whose stock prices the portfolio managers believe to be undervalued. The Fund may also invest in foreign equity and debt securities, which may include investments in emerging markets.

The Fund focuses on companies that have fallen out of favor with the market or that appear to be temporarily misunderstood by the investment community. The Fund’s portfolio managers generally look for companies with:

• strong balance sheets and solid recurring free cash flows

• attractive relative and absolute valuation ratios or that have underperformed recently

• favorable reward to risk characteristics

The Fund may invest its assets in derivatives, which are instruments that have a value derived from or directly linked to an underlying asset, such as equity securities, bonds, commodities, currencies, interest rates, or market indices, as substitutes for securities in which the Fund invests. The Fund may invest in derivative instruments (by taking long and/or short positions) for different purposes, including hedging (to offset risks associated with an investment, currency exposure, or market conditions) and to earn income and enhance returns. For more information on the Fund’s use of derivatives, refer to the Fund’s shareholder reports and Form N-Q reports, which are filed with the Securities and Exchange Commission, when available.
Principal Investment Risks jif277751_PrincipalInvestmentRisksAbstract  
Risk [Heading] rr_RiskHeading PRINCIPAL INVESTMENT RISKS
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock

The biggest risk is that the Fund’s returns will vary, and you could lose money. The Fund is designed for long-term investors seeking an equity portfolio, including common stocks. Common stocks tend to be more volatile than many other investment choices.

Value Investing Risk. Because different types of stocks tend to shift in and out of favor depending on market and economic conditions, “value” stocks may perform differently than other types of stocks and from the market as a whole, and can continue to be undervalued by the market for long periods of time. It is also possible that a value stock will never appreciate to the extent expected.

Market Risk. The value of the Fund’s portfolio may decrease if the value of an individual company or security, or multiple companies or securities, in the portfolio decreases or if the portfolio managers’ belief about a company’s intrinsic worth is incorrect. Further, regardless of how well individual companies or securities perform, the value of the Fund’s portfolio could also decrease if there are deteriorating economic or market conditions. It is important to understand that the value of your investment may fall, sometimes sharply, in response to changes in the market, and you could lose money.

Foreign Exposure Risk. The Fund may have exposure to foreign markets, including emerging markets, which can be more volatile than the U.S. markets. As a result, its returns and net asset value may be affected to a large degree by fluctuations in currency exchange rates or political or economic conditions in a particular country. In some foreign markets, there may not be protection against failure by other parties to complete transactions. It may not be possible for the Fund to repatriate capital, dividends, interest, and other income from a particular country or governmental entity. In addition, a market swing in one or more countries or regions where the Fund has invested a significant amount of its assets may have a greater effect on the Fund’s performance than it would in a more geographically diversified portfolio. The Fund’s investments in emerging market countries may involve risks greater than, or in addition to, the risks of investing in more developed countries.

Derivatives Risk. Derivatives can be highly volatile and involve risks in addition to the risks of the underlying referenced securities. Gains or losses from a derivative can be substantially greater than the derivative’s original cost, and can therefore involve leverage. Derivatives can be less liquid than other types of investments and entail the risk that the counterparty will default on its payment obligations.

An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Risk Lose Money [Text] rr_RiskLoseMoney The biggest risk is that the Fund’s returns will vary, and you could lose money.
Risk Not Insured Depository Institution [Text] rr_RiskNotInsuredDepositoryInstitution An investment in the Fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
PERFORMANCE INFORMATION jif277751_FundPastPerformanceAbstract  
Bar Chart and Performance Table [Heading] rr_BarChartAndPerformanceTableHeading PERFORMANCE INFORMATION
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock The Fund does not have a full calendar year of operations. Performance information for certain periods will be included in the Fund’s first annual and/or semiannual report.
Performance One Year or Less [Text] rr_PerformanceOneYearOrLess The Fund does not have a full calendar year of operations.
Perkins Select Value Fund | Class D Shares | Class D
  
ANNUAL FUND OPERATING EXPENSES rr_OperatingExpensesAbstract  
Operating Expenses Column [Text] rr_OperatingExpensesColumnName Class D
Management Fees (may adjust up or down) rr_ManagementFeesOverAssets 0.70%
Other Expenses rr_OtherExpensesOverAssets 0.65% [1]
Total Annual Fund Operating Expenses rr_ExpensesOverAssets 1.35% [3]
Fee Waiver rr_FeeWaiverOrReimbursementOverAssets 0.19% [3]
Net Annual Fund Operating Expenses After Fee Waiver rr_NetExpensesOverAssets 1.16% [3]
EXAMPLE: rr_ExpenseExampleAbstract  
Expense Example, By Year, Column [Text] rr_ExpenseExampleByYearColumnName Class D Shares
1 Year rr_ExpenseExampleYear01 137
3 Years rr_ExpenseExampleYear03 427
[1] Since the Fund is new, Other Expenses are based on the estimated expenses that the Fund expects to incur in its initial fiscal period.
[2] Janus Capital has contractually agreed to waive the Fund's total annual fund operating expenses (excluding any performance adjustments to management fees, the distribution and shareholder servicing fees - applicable to Class A Shares, Class C Shares, and Class S Shares; administrative services fees payable pursuant to the Transfer Agency Agreement (except for networking and omnibus fees); brokerage commissions; interest; dividends; taxes; and extraordinary expenses including, but not limited to, acquired fund fees and expenses) to 1.00% until at least November 1, 2013. The contractual waiver may be terminated or modified prior to this date only at the discretion of the Board of Trustees.
[3] Janus Capital has contractually agreed to waive the Fund's total annual fund operating expenses (excluding any performance adjustments to management fees, administrative services fees payable pursuant to the Transfer Agency Agreement, brokerage commissions, interest, dividends, taxes, and extraordinary expenses including, but not limited to, acquired fund fees and expenses) to 1.00% until at least November 1, 2013. The contractual waiver may be terminated or modified prior to this date only at the discretion of the Board of Trustees.