Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	JANUS INVESTMENT FUND
Prospectus Date	rr_ProspectusDate	Oct. 28, 2013
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	FUND SUMMARY INTECH U.S. Growth Fund
Objective [Heading]	rr_ObjectiveHeading	INVESTMENT OBJECTIVE
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	INTECH U.S. Growth Fund seeks long-term growth of capital.
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.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	SHAREHOLDER FEES (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	ANNUAL FUND OPERATING EXPENSES (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio Turnover:
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 81% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	81.00%
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 51 of the Fund’s Prospectus and in the “Purchases” section on page 70 of the Fund’s Statement of Additional Information.
Expense Breakpoint, Minimum Investment Required [Amount]	rr_ExpenseBreakpointMinimumInvestmentRequiredAmount	$ 50,000
Expense Example [Heading]	rr_ExpenseExampleHeading	EXAMPLE:
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 remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	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, Caption [Text]	rr_ExpenseExampleByYearCaption	If Shares are redeemed:
Expense Example, No Redemption, By Year, Caption [Text]	rr_ExpenseExampleNoRedemptionByYearCaption	If Shares are not redeemed:
Strategy [Heading]	rr_StrategyHeading	PRINCIPAL INVESTMENT STRATEGIES
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Fund invests, under normal circumstances, at least 80% of its net assets in U.S. common stocks from the universe of the Russell 1000® Growth Index, utilizing INTECH’s mathematical investment process. The Russell 1000® Growth Index is an unmanaged index that measures the performance of those Russell 1000 companies with higher price-to-book ratios and higher forecasted growth values. The Fund pursues its investment objective by applying a mathematical investment process to construct an investment portfolio from the universe of common stocks within its named benchmark index. The goal of this process is to build a portfolio of stocks in a more efficient combination than the named benchmark index. The process seeks to capitalize on the natural volatility of the market by searching for stocks within the index that have high relative volatility (providing the potential for excess returns) but that essentially move in opposite directions or have low correlation to each other (providing the potential for lower relative risk). By constructing the portfolio in this manner and periodically rebalancing the portfolio to maintain potentially more efficient weightings, INTECH’s mathematical investment process seeks to create a portfolio that, over time, produces returns in excess of its named benchmark index with risks similar to that of the benchmark index. The rebalancing techniques used by INTECH may result in a higher portfolio turnover compared to a “buy and hold” fund strategy. The Fund may lend portfolio securities on a short-term or long-term basis, in an amount equal to up to 1/3 of its total assets as determined at the time of the loan origination.
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. Growth Securities Risk. Securities of companies perceived to be “growth” companies may be more volatile than other stocks and may involve special risks. If a company’s growth potential is not realized, the securities purchased may not perform as expected, reducing the Fund’s returns. In addition, because different types of stocks tend to shift in and out of favor depending on market and economic conditions, “growth” stocks may perform differently from the market as a whole and other types of securities. 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. 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. Investment Process Risk. The proprietary mathematical investment process used by INTECH may not achieve the desired results. There is a risk that INTECH’s method of identifying stocks with higher volatility than the named benchmark index or its method of identifying stocks that tend to move in the same or opposite direction relative to each other (correlation) will not result in selecting stocks with continuing volatility or the expected correlation. In INTECH’s history, which spans more than 25 years, INTECH’s mathematical investment process has experienced periods of both underperformance and outperformance relative to an identified benchmark. Even when the proprietary mathematical investment process is working appropriately, INTECH expects that there will be periods of underperformance relative to the benchmark. On an occasional basis, INTECH makes changes to its mathematical investment process. These changes may result in changes to the portfolio, might not provide the intended results, and may adversely impact the Fund’s performance. Portfolio Turnover Risk. Increased portfolio turnover may result in higher costs, which may have a negative effect on the Fund’s performance. In addition, higher portfolio turnover may result in the acceleration of capital gains and the recognition of greater levels of short-term capital gains, which are taxed at ordinary federal income tax rates when distributed to shareholders. Securities Lending Risk. The Fund may seek to earn additional income through lending its securities to certain qualified broker-dealers and institutions. There is the risk that when portfolio securities are lent, the securities may not be returned on a timely basis, and the Fund may experience delays and costs in recovering the security or gaining access to the collateral provided to the Fund to collateralize the loan. If the Fund is unable to recover a security on loan, the Fund may use the collateral to purchase replacement securities in the market. There is a risk that the value of the collateral could decrease below the cost of the replacement security by the time the replacement investment is made, resulting in a loss to the Fund. 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.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	PERFORMANCE INFORMATION
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. Class S Shares, Class A Shares, Class C Shares, and Class I Shares of the Fund commenced operations on July 6, 2009, after the reorganization of each corresponding class of shares of Janus Adviser INTECH Risk-Managed Growth Fund (“JAD predecessor fund”) into each respective share class of the Fund. Class T Shares of the Fund commenced operations on July 6, 2009. The performance shown for Class S Shares for periods prior to July 6, 2009, reflects the historical performance of the JAD predecessor fund’s Class S Shares prior to the reorganization, calculated using the fees and expenses of the JAD predecessor fund’s Class S Shares, net of any applicable fee and expense limitations or waivers. The performance shown for Class A Shares reflects the performance of the JAD predecessor fund’s Class A Shares from September 30, 2004 to July 6, 2009 (prior to the reorganization), calculated using the fees and expenses of Class A Shares of the JAD predecessor fund, net of any applicable fee and expense limitations or waivers. Performance shown for certain periods prior to September 30, 2004 reflects the historical performance of the JAD predecessor fund’s Class S Shares (formerly named Class I Shares), calculated using the fees and expenses of Class S Shares of the JAD predecessor fund, net of any applicable fee and expense limitations or waivers. The performance shown for Class C Shares for periods prior to July 6, 2009, reflects the historical performance of the JAD predecessor fund’s Class C Shares prior to the reorganization, calculated using the fees and expenses of the JAD predecessor fund’s Class C Shares, net of any applicable fee and expense limitations or waivers. The performance shown for Class I Shares reflects the performance of the JAD predecessor fund’s Class I Shares from November 28, 2005 to July 6, 2009 (prior to the reorganization), calculated using the fees and expenses of Class I Shares of the JAD predecessor fund, net of any applicable fee and expense limitations or waivers. Performance shown for certain periods prior to November 28, 2005 reflects the historical performance of the JAD predecessor fund’s Class S Shares (formerly named Class I Shares), calculated using the fees and expenses of Class S Shares of the JAD predecessor fund, net of any applicable fee and expense limitations or waivers. The performance shown for Class T Shares for periods prior to July 6, 2009, reflects the historical performance of the JAD predecessor fund’s Class S Shares prior to the reorganization, calculated using the fees and expenses of Class S Shares, net of any applicable fee and expense limitations or waivers. If Class A Shares, Class I Shares, and Class T Shares of the Fund had been available during periods prior to July 6, 2009, the performance shown for each respective share class may have been different. The performance shown for periods following the Fund’s commencement of Class S Shares, Class A Shares, Class C Shares, Class I Shares, and Class T Shares reflects the fees and expenses of each respective share class, net of any applicable fee and expense limitations or waivers. The bar chart depicts the change in performance from year to year during the periods indicated. The bar chart figures do not include any applicable sales charges that an investor may pay when they buy or sell Class A Shares or Class C Shares of the Fund. If sales charges were included, the returns would be lower. The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index. The index is not actively managed and is not available for direct investment. All figures assume reinvestment of dividends and distributions. For certain periods, the Fund’s performance reflects the effect of expense waivers. Without the effect of these expense waivers, the performance shown would have been lower. The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future. Updated performance information is available at janus.com/advisor/mutual-funds or by calling 1-877-335-2687.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The following information provides some indication of the risks of investing in the Fund by showing how the Fund’s performance has varied over time. The bar chart depicts the change in performance from year to year during the periods indicated.
Performance Additional Market Index [Text]	rr_PerformanceAdditionalMarketIndex	The table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index. The index is not actively managed and is not available for direct investment. All figures assume reinvestment of dividends and distributions.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	1-877-335-2687
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	janus.com/advisor/mutual-funds
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund’s past performance (before and after taxes) does not necessarily indicate how it will perform in the future.
Bar Chart [Heading]	rr_BarChartHeading	Annual Total Returns for Class S Shares (calendar year-end)
Bar Chart Does Not Reflect Sales Loads [Text]	rr_BarChartDoesNotReflectSalesLoads	The bar chart figures do not include any applicable sales charges that an investor may pay when they buy or sell Class A Shares or Class C Shares of the Fund. If sales charges were included, the returns would be lower.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter:  Second Quarter 2009  15.04%          Worst Quarter:  Fourth Quarter 2008  −25.11%
Year to Date Return, Label	rr_YearToDateReturnLabel	The Fund’s year-to-date return as of the calendar quarter ended September 30, 2013 was 20.79%.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (periods ended 12/31/12)
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the historically highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-deferred account, such as a 401(k) plan or an IRA.
Performance Table One Class of after Tax Shown [Text]	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are only shown for Class S Shares of the Fund. After-tax returns for the other classes of Shares will vary from those shown for Class S Shares due to varying sales charges (as applicable), fees, and expenses among the classes.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using distributions for the Fund’s Class S Shares for periods following July 6, 2009; and for the JAD predecessor fund’s Class S Shares (formerly named Class I Shares) for periods prior to July 6, 2009. After-tax returns are calculated using the historically highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on your individual tax situation and may differ from those shown in the preceding table. The after-tax return information shown above does not apply to Fund shares held through a tax-deferred account, such as a 401(k) plan or an IRA. After-tax returns are only shown for Class S Shares of the Fund. After-tax returns for the other classes of Shares will vary from those shown for Class S Shares due to varying sales charges (as applicable), fees, and expenses among the classes.
Performance Table Closing [Text Block]	rr_PerformanceTableClosingTextBlock	Updated performance information is available at janus.com/advisor/mutual-funds or by calling 1-877-335-2687.
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares | Class A
Risk/Return:	rr_RiskReturnAbstract
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
Operating Expenses Column [Text]	rr_OperatingExpensesColumnName	Class A
Management Fees	rr_ManagementFeesOverAssets	0.50%
Distribution/Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other Expenses	rr_OtherExpensesOverAssets	0.15%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.90%
Expense Example, By Year, Column [Text]	rr_ExpenseExampleByYearColumnName	Class A Shares
1 Year	rr_ExpenseExampleYear01	662
3 Years	rr_ExpenseExampleYear03	845
5 Years	rr_ExpenseExampleYear05	1,045
10 Years	rr_ExpenseExampleYear10	1,619
Expense Example, No Redemption, By Year, Column [Text]	rr_ExpenseExampleNoRedemptionByYearColumnName	Class A Shares
1 Year	rr_ExpenseExampleNoRedemptionYear01	662
3 Years	rr_ExpenseExampleNoRedemptionYear03	845
5 Years	rr_ExpenseExampleNoRedemptionYear05	1,045
10 Years	rr_ExpenseExampleNoRedemptionYear10	1,619
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares | Class C
Risk/Return:	rr_RiskReturnAbstract
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%
Operating Expenses Column [Text]	rr_OperatingExpensesColumnName	Class C
Management Fees	rr_ManagementFeesOverAssets	0.50%
Distribution/Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other Expenses	rr_OtherExpensesOverAssets	0.10%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.60%
Expense Example, By Year, Column [Text]	rr_ExpenseExampleByYearColumnName	Class C Shares
1 Year	rr_ExpenseExampleYear01	263
3 Years	rr_ExpenseExampleYear03	505
5 Years	rr_ExpenseExampleYear05	871
10 Years	rr_ExpenseExampleYear10	1,900
Expense Example, No Redemption, By Year, Column [Text]	rr_ExpenseExampleNoRedemptionByYearColumnName	Class C Shares
1 Year	rr_ExpenseExampleNoRedemptionYear01	163
3 Years	rr_ExpenseExampleNoRedemptionYear03	505
5 Years	rr_ExpenseExampleNoRedemptionYear05	871
10 Years	rr_ExpenseExampleNoRedemptionYear10	1,900
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares | Class S
Risk/Return:	rr_RiskReturnAbstract
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
Operating Expenses Column [Text]	rr_OperatingExpensesColumnName	Class S
Management Fees	rr_ManagementFeesOverAssets	0.50%
Distribution/Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other Expenses	rr_OtherExpensesOverAssets	0.31%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.06%
Expense Example, By Year, Column [Text]	rr_ExpenseExampleByYearColumnName	Class S Shares
1 Year	rr_ExpenseExampleYear01	108
3 Years	rr_ExpenseExampleYear03	337
5 Years	rr_ExpenseExampleYear05	585
10 Years	rr_ExpenseExampleYear10	1,294
Expense Example, No Redemption, By Year, Column [Text]	rr_ExpenseExampleNoRedemptionByYearColumnName	Class S Shares
1 Year	rr_ExpenseExampleNoRedemptionYear01	108
3 Years	rr_ExpenseExampleNoRedemptionYear03	337
5 Years	rr_ExpenseExampleNoRedemptionYear05	585
10 Years	rr_ExpenseExampleNoRedemptionYear10	1,294
2004	rr_AnnualReturn2004	12.34%
2005	rr_AnnualReturn2005	6.90%
2006	rr_AnnualReturn2006	6.90%
2007	rr_AnnualReturn2007	10.30%
2008	rr_AnnualReturn2008	(42.71%)
2009	rr_AnnualReturn2009	32.84%
2010	rr_AnnualReturn2010	17.50%
2011	rr_AnnualReturn2011	1.73%
2012	rr_AnnualReturn2012	15.24%
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2013
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	20.79%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter:
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Jun. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	15.04%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter:
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2008
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(25.11%)
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares | Class I
Risk/Return:	rr_RiskReturnAbstract
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
Operating Expenses Column [Text]	rr_OperatingExpensesColumnName	Class I
Management Fees	rr_ManagementFeesOverAssets	0.50%
Distribution/Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.08%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.58%
Expense Example, By Year, Column [Text]	rr_ExpenseExampleByYearColumnName	Class I Shares
1 Year	rr_ExpenseExampleYear01	59
3 Years	rr_ExpenseExampleYear03	186
5 Years	rr_ExpenseExampleYear05	324
10 Years	rr_ExpenseExampleYear10	726
Expense Example, No Redemption, By Year, Column [Text]	rr_ExpenseExampleNoRedemptionByYearColumnName	Class I Shares
1 Year	rr_ExpenseExampleNoRedemptionYear01	59
3 Years	rr_ExpenseExampleNoRedemptionYear03	186
5 Years	rr_ExpenseExampleNoRedemptionYear05	324
10 Years	rr_ExpenseExampleNoRedemptionYear10	726
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares | Class T
Risk/Return:	rr_RiskReturnAbstract
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
Operating Expenses Column [Text]	rr_OperatingExpensesColumnName	Class T
Management Fees	rr_ManagementFeesOverAssets	0.50%
Distribution/Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.31%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.81%
Expense Example, By Year, Column [Text]	rr_ExpenseExampleByYearColumnName	Class T Shares
1 Year	rr_ExpenseExampleYear01	83
3 Years	rr_ExpenseExampleYear03	259
5 Years	rr_ExpenseExampleYear05	450
10 Years	rr_ExpenseExampleYear10	1,002
Expense Example, No Redemption, By Year, Column [Text]	rr_ExpenseExampleNoRedemptionByYearColumnName	Class T Shares
1 Year	rr_ExpenseExampleNoRedemptionYear01	83
3 Years	rr_ExpenseExampleNoRedemptionYear03	259
5 Years	rr_ExpenseExampleNoRedemptionYear05	450
10 Years	rr_ExpenseExampleNoRedemptionYear10	$ 1,002
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares | Return Before Taxes | Class A
Risk/Return:	rr_RiskReturnAbstract
Column	rr_AverageAnnualReturnColumnName	Class A Shares
Label	rr_AverageAnnualReturnLabel	Return Before Taxes	[1]
1 Year	rr_AverageAnnualReturnYear01	8.69%
5 Years	rr_AverageAnnualReturnYear05	(0.05%)
Since Inception of Predecessor Fund	rr_AverageAnnualReturnSinceInception	5.95%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 02, 2003
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares | Return Before Taxes | Class C
Risk/Return:	rr_RiskReturnAbstract
Column	rr_AverageAnnualReturnColumnName	Class C Shares
Label	rr_AverageAnnualReturnLabel	Return Before Taxes	[2]
1 Year	rr_AverageAnnualReturnYear01	13.35%
5 Years	rr_AverageAnnualReturnYear05	0.29%
Since Inception of Predecessor Fund	rr_AverageAnnualReturnSinceInception	5.76%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 02, 2003
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares | Return Before Taxes | Class S
Risk/Return:	rr_RiskReturnAbstract
Column	rr_AverageAnnualReturnColumnName	Class S Shares
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	15.24%
5 Years	rr_AverageAnnualReturnYear05	0.95%
Since Inception of Predecessor Fund	rr_AverageAnnualReturnSinceInception	6.38%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 02, 2003
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares | Return Before Taxes | Class I
Risk/Return:	rr_RiskReturnAbstract
Column	rr_AverageAnnualReturnColumnName	Class I Shares
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	15.70%
5 Years	rr_AverageAnnualReturnYear05	1.41%
Since Inception of Predecessor Fund	rr_AverageAnnualReturnSinceInception	6.38%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 02, 2003
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares | Return Before Taxes | Class T
Risk/Return:	rr_RiskReturnAbstract
Column	rr_AverageAnnualReturnColumnName	Class T Shares
Label	rr_AverageAnnualReturnLabel	Return Before Taxes
1 Year	rr_AverageAnnualReturnYear01	15.53%
5 Years	rr_AverageAnnualReturnYear05	0.95%
Since Inception of Predecessor Fund	rr_AverageAnnualReturnSinceInception	6.38%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 02, 2003
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares | Return After Taxes on Distributions | Class S
Risk/Return:	rr_RiskReturnAbstract
Column	rr_AverageAnnualReturnColumnName	Class S Shares
Label	rr_AverageAnnualReturnLabel	Return After Taxes on Distributions
1 Year	rr_AverageAnnualReturnYear01	15.08%
5 Years	rr_AverageAnnualReturnYear05	0.84%
Since Inception of Predecessor Fund	rr_AverageAnnualReturnSinceInception	5.89%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 02, 2003
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares | Return After Taxes on Distributions and Sale of Fund Shares | Class S
Risk/Return:	rr_RiskReturnAbstract
Column	rr_AverageAnnualReturnColumnName	Class S Shares
Label	rr_AverageAnnualReturnLabel	Return After Taxes on Distributions and Sale of Fund Shares
1 Year	rr_AverageAnnualReturnYear01	10.12%
5 Years	rr_AverageAnnualReturnYear05	0.79%
Since Inception of Predecessor Fund	rr_AverageAnnualReturnSinceInception	5.41%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 02, 2003
INTECH U.S. Growth Fund | Class A, C, S, I, T Shares | Russell 1000® Growth Index (reflects no deduction for expenses, fees, or taxes)
Risk/Return:	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Russell 1000® Growth Index
1 Year	rr_AverageAnnualReturnYear01	15.26%
5 Years	rr_AverageAnnualReturnYear05	3.12%
Since Inception of Predecessor Fund	rr_AverageAnnualReturnSinceInception	7.16%
Inception Date	rr_AverageAnnualReturnInceptionDate	Jan. 02, 2003

[1] Calculated assuming maximum permitted sales loads.

[2] The one year return is calculated to include the contingent deferred sales charge.