Label	Element	Value
Risk Return Abstract	rr_RiskReturnAbstract
Prospectus Date	rr_ProspectusDate	Oct. 28, 2021
Class D Shares | Janus Henderson Dividend and Income Builder Fund
Risk Return Abstract	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	<span style="color:#000000;font-family:Times New Roman;font-size:15.20pt;font-weight:bold;margin-left:3pt;">Janus Henderson Dividend & Income Builder Fund</span>
Objective [Heading]	rr_ObjectiveHeading	<span style="color:#FFFFFF;font-family:Times New Roman;font-size:10.45pt;font-weight:bold;padding-left:0.0%;text-transform:uppercase;">Investment Objectives</span>
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	Janus Henderson Dividend & Income Builder Fund seeks to provide current income from a portfolio of securities that exceeds the average yield on global stocks, and aims to provide a growing stream of income per share over time.
Objective, Secondary [Text Block]	rr_ObjectiveSecondaryTextBlock	The Fund’s secondary objective is to seek to provide long-term capital appreciation.
Expense [Heading]	rr_ExpenseHeading	<span style="color:#FFFFFF;font-family:Times New Roman;font-size:10.45pt;font-weight:bold;padding-left:0.0%;text-transform:uppercase;">Fees and Expenses of the Fund</span>
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.
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)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	<span style="color:#000000;font-family:Times New Roman;font-size:7.60pt;">The Adviser has contractually agreed to waive its investment advisory fee and/or reimburse operating expenses to the extent that the Fund’s total annual fund operating expenses (excluding shareholder servicing fees, such as transfer agency fees (including out-of-pocket costs), administrative services fees, brokerage commissions, interest, dividends, taxes, acquired fund fees and expenses, and extraordinary expenses) exceed 0.84% for at least a one-year period commencing on October 28, 2021. The contractual waiver may be terminated or modified prior to this date only at the discretion of the Board of Trustees.</span>
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	<span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;font-weight:bold;">Portfolio Turnover:</span>
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 52% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	52.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	<span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;font-weight:bold;margin-left:3pt;">EXAMPLE:</span>
Expense Example by Year [Heading]	rr_ExpenseExampleByYearHeading	<span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;"> 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:</span>
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.
Strategy [Heading]	rr_StrategyHeading	<span style="color:#FFFFFF;font-family:Times New Roman;font-size:10.45pt;font-weight:bold;padding-left:0.0%;text-transform:uppercase;">Principal investment strategies</span>
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Fund pursues its investment objective by investing, under normal circumstances, at least 80% of its net assets (plus any borrowings for investment purposes) in a portfolio of income-producing securities. The Fund normally invests at least 50% of its assets in equity securities, and up to 30% of its assets in fixed-income securities.The Fund will normally invest its assets primarily in dividend-paying equities as well as a range of fixed-income securities, including high-yield corporate bonds (also known as “junk” bonds), investment grade bonds, sovereign debt from issuers in the United States and around the world, unrated bonds and floating rate securities.In selecting investments, the Fund seeks to invest in securities that the portfolio managers believe offer the potential for growth of income and capital over time. The portfolio managers may shift the Fund’s assets among various types of income-producing securities based on changing market conditions.For the Fund’s investment in equity securities, the portfolio managers primarily seek to invest in common stocks of companies with attractive long-term business prospects that generate profits and produce attractive levels of dividend income, and which are, in the opinion of the portfolio managers, undervalued or inexpensive relative to other comparable investments. The Fund may also invest in preferred stocks, depository receipts, equity real estate investment trusts (“REITs”), and other equity-related securities. The Fund generally measures the average yield on global stocks by reference to the MSCI World Indexsm.The Fund may invest in a variety of fixed-income securities, including bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. companies, governments or other public sector entities. The Fund may invest in fixed-income securities across the maturity range and of any credit quality.The Fund invests in U.S. and non-U.S. issuers and has no specific policy on the number of different countries in which it will invest but intends to invest in at least three different countries. The Fund may invest in companies domiciled in any country that the portfolio managers believe to be appropriate in pursuit of the Fund’s objectives and may invest in securities of companies or issuers based in and/or economically tied to emerging markets. There is no limitation on the market capitalization range of issuers in which the Fund may invest. The Fund’s investment in an issuer may be effected through an initial public offering and/or a private placement.The Fund may also invest a substantial amount of its assets (i.e., more than 25% of its assets) in issuers located in a single country or a limited number of countries.The Fund will generally consider selling a security when, in the portfolio managers’ opinion, there is a risk of significant deterioration in the company’s fundamentals, or there is a change in business strategy or issuer-specific business outlook that affects the original investment case. The Fund will also consider selling a security if, in the portfolio managers’ opinion, a superior investment opportunity arises.Although the Fund does not have a specific policy regarding the growth/value orientation or market capitalization of the companies in which it invests, the portfolio managers believe that focusing on income-producing equity securities will tend to lead to investments in mid-to-large capitalization “value” stocks with a market capitalization greater than $3 billion (stocks of well-established, undervalued companies that the portfolio managers believe offer the potential for income and long-term capital appreciation). The portfolio managers may, however, invest in smaller and less seasoned issuers and in stocks that are considered “growth” stocks.The Fund may lend portfolio securities on a short-term or long-term basis, in an amount equal to up to one-third of its total assets as determined at the time of the loan origination.
Risk [Heading]	rr_RiskHeading	<span style="color:#FFFFFF;font-family:Times New Roman;font-size:10.45pt;font-weight:bold;padding-left:0.0%;text-transform:uppercase;">Principal investment risks</span>
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 income-producing portfolio, including fixed-income securities and dividend-paying equities, such as common stocks. Common stocks tend to be more volatile than many other investment choices. The principal risks associated with investing in the Fund are set forth below.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. Market risk may affect a single issuer, industry, economic sector, or the market as a whole. Market risk may be magnified if certain social, political, economic, and other conditions and events (such as terrorism, conflicts, social unrest, natural disasters, epidemics and pandemics, including COVID-19) adversely interrupt the global economy and financial markets.Allocation Risk. The Fund’s ability to achieve its investment objective depends largely upon the allocation of assets among the equity and fixed-income asset categories. You could lose money on your investment in the Fund as a result of these allocations. Portfolio management may favor an asset category that underperforms relative to other asset categories. For example, the Fund may be overweighted in fixed-income securities when the stock market is rising and the fixed-income market is falling. Additionally, periodic rebalancing of Fund assets among asset categories may result in increased transaction costs, which may have a negative effect on the Fund’s performance.Foreign Exposure Risk. The Fund may have significant exposure to foreign markets as a result of its investments in foreign securities and derivatives that provide exposure to foreign markets, including investments in 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. To the extent the Fund invests in foreign debt securities, such investments are sensitive to changes in interest rates. Additionally, investments in securities of foreign governments involve the risk that a foreign government may not be willing or able to pay interest or repay principal when due. Some of the risks of investing directly in foreign securities may be reduced when the Fund invests indirectly in such securities through various other investment vehicles including derivatives, but such investments also involve other risks. The Fund’s investments in emerging market countries, if any, may involve risks greater than, or in addition to, the risks of investing in more developed countries.Fixed-Income Securities Risk. The Fund invests in a variety of fixed-income securities and derivatives. A fundamental risk of fixed-income securities is interest rate risk, which is the risk that prices of bonds and other fixed-income securities will increase as interest rates fall and decrease as interest rates rise. The Fund may be subject to a greater risk of rising interest rates due to the current period of historically low rates. How specific fixed-income securities may react to changes in interest rates will depend on the specific characteristics of each security. For example, while securities with longer maturities and durations tend to offer higher yields, they also tend to be more sensitive to changes in prevailing interest rates and are therefore more volatile than shorter-term securities and are subject to greater market fluctuations as a result of changes in interest rates. Fixed-income securities are also subject to credit risk, prepayment risk, extension risk, valuation risk, and liquidity risk.•Credit risk is the risk that the credit strength of an issuer of a fixed-income security will weaken and/or that the issuer will be unable to make timely principal and interest payments and that the security may go into default.•Prepayment risk is the risk that, during periods of falling interest rates, certain debt obligations may be paid off quicker than originally anticipated, which may cause the Fund to reinvest its assets in securities with lower yields, resulting in a decline in the Fund’s income or return potential.•Extension risk is the risk that, during periods of rising interest rates, certain debt obligations may be paid off substantially slower than originally anticipated, and the value of those securities may fall, resulting in a decline in the Fund’s income and potentially in the value of the Fund’s investments.•Valuation risk is the risk that one or more of the fixed-income securities in which the Fund invests are priced differently than the value realized upon such security’s sale. In times of market instability, valuation may be more difficult.•Liquidity risk is the risk that fixed-income securities may be difficult or impossible to sell at the time that the portfolio managers would like or at the price the portfolio managers believe the security is currently worth.Value Investing Risk. The Fund may invest in value stocks. 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 by the portfolio managers.Geographic Concentration Risk. To the extent the Fund invests a substantial amount of its assets in issuers located in a single country or region, the economic, political, social, regulatory, or other developments or conditions within such country or region will generally have a greater effect on the Fund than they would on a more geographically diversified fund, which may result in greater losses and volatility. Adverse developments in certain regions could also adversely affect securities of other countries whose economies appear to be unrelated and could have a negative impact on the Fund’s performance.Emerging Markets Risk. The risks of foreign investing are heightened when investing in emerging markets. Emerging market securities involve a number of additional risks, which may result from less government supervision and regulation of business and industry practices (including the potential lack of strict finance and accounting controls and standards), stock exchanges, brokers, and listed companies. Information about emerging market companies, including financial information, may be less available or reliable and the Adviser’s ability to conduct due diligence with respect to such companies may be limited. Accordingly, these investments may be potentially more volatile in price and less liquid than investments in developed securities markets, resulting in greater risk to investors. There is a risk in developing countries that a current or future economic or political crisis could lead to price controls, forced mergers of companies, expropriation or confiscatory taxation, imposition or enforcement of foreign ownership limits, seizure, nationalization, sanctions or imposition of restrictions by various governmental entities on investment and trading, or creation of government monopolies, any of which may have a detrimental effect on the Fund’s investments. In addition, the taxation systems at the federal, regional, and local levels in developing or emerging market countries may be less transparent, inconsistently enforced, and subject to change. Emerging markets may be subject to a higher degree of corruption and fraud than developed markets and financial institutions and transaction counterparties may have less financial sophistication, creditworthiness, and/or resources than participants in developed markets. In addition, the Fund’s investments may be denominated in foreign currencies and therefore, changes in the value of a country’s currency compared to the U.S. dollar may affect the value of the Fund’s investments.High-Yield/High-Risk Bond Risk. High-yield/high-risk bonds are considered speculative and may be more sensitive than other types of bonds to economic changes, political changes, or adverse developments specific to the company that issued the bond, which may adversely affect their value.Sovereign Debt Risk. The Fund may invest, directly or indirectly, in U.S. and non-U.S. government debt securities (“sovereign debt”). Some investments in sovereign debt, such as U.S. sovereign debt, are considered low risk. However, investments in sovereign debt, especially the debt of less developed countries, can involve a high degree of risk, including the risk that the governmental entity that controls the repayment of sovereign debt may not be willing or able to repay the principal and/or to pay the interest on its sovereign debt in a timely manner. A sovereign debtor’s willingness or ability to satisfy its debt obligation may be affected by various factors including, but not limited to, its cash flow situation, the extent of its foreign currency reserves, the availability of foreign exchange when a payment is due, and the relative size of its debt position in relation to its economy as a whole. In the event of default, there may be limited or no legal remedies for collecting sovereign debt and there may be no bankruptcy proceedings through which the Fund may collect all or part of the sovereign debt that a governmental entity has not repaid. In addition, to the extent the Fund invests in non-U.S. sovereign debt, it may be subject to currency risk.Real Estate Securities Risk. The Fund’s performance may be affected by the risks associated with investments in real estate-related companies. The value of real estate-related companies’ securities is sensitive to changes in real estate values and rental income, property taxes, interest rates, tax and regulatory requirements, supply and demand, and the management skill and creditworthiness of the company. Investments in REITs involve the same risks as other real estate investments. In addition, a REIT could fail to qualify for tax-free pass-through of its income under the Internal Revenue Code of 1986, as amended, or fail to maintain its exemption from registration under the Investment Company Act of 1940, as amended, which could produce adverse economic consequences for the REIT and its investors, including the Fund.Small- and Mid-Sized Companies Risk. The Fund’s investments in securities issued by small- and mid-sized companies, which can include smaller, start-up companies offering emerging products or services, may involve greater risks than are customarily associated with larger, more established companies. Securities issued by small- and mid-sized companies tend to be more volatile and somewhat more speculative than securities issued by larger or more established companies and may underperform as compared to the securities of larger or more established companies.Initial Public Offering Risk. The Fund’s purchase of shares issued in an initial public offering (“IPO”) exposes it to the risks associated with companies that have little operating history as public companies, as well as to the risks inherent in those sectors of the market where these new issuers operate. Although IPO investments may have had a positive impact on the Fund’s performance in the past, there can be no assurance that the Fund will identify favorable IPO investment opportunities in the future. In addition, as the Fund increases in size, the impact of IPOs on the Fund’s performance will generally decrease.Restricted Securities Risk. Securities that have limitations on their resale are referred to as “restricted securities.” Investments in restricted securities, including securities issued under Regulation S and Rule 144A, could have the effect of decreasing the Fund’s liquidity profile or preventing the Fund from disposing of them promptly at advantageous prices. Restricted securities may be less liquid than other investments because such securities may not always be readily sold in broad public markets and may have no active trading market. As a result, they may be difficult to value because market quotations may not be readily available.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.Portfolio Management Risk. The Fund is an actively managed investment portfolio and is therefore subject to the risk that the investment strategies employed for the Fund may fail to produce the intended results. The Fund may underperform its benchmark index or other mutual funds with similar investment objectives.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	<span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;">The biggest risk is that the Fund’s returns will vary, and you could lose money.</span>
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	<span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;font-style:italic;">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.</span>
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	<span style="color:#FFFFFF;font-family:Times New Roman;font-size:10.45pt;font-weight:bold;padding-left:0.0%;text-transform:uppercase;">Performance information</span>
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 D Shares of the Fund commenced operations on June 5, 2017. The performance shown for Class D Shares for periods prior to June 5, 2017, reflects the performance of Class I Shares of Henderson Dividend & Income Builder Fund (the “Predecessor Fund”), calculated using the estimated fees and expenses of Class D Shares, net of any applicable fee and expense limitations or waivers. The Predecessor Fund was advised by Henderson Global Investors (North America) Inc. and subadvised by Henderson Investment Management Limited. Class A Shares, Class C Shares, Class I Shares, and Class R6 Shares of the Predecessor Fund were reorganized into Class A Shares, Class C Shares, Class I Shares, and Class N Shares, respectively, of the Fund on June 2, 2017. In connection with this reorganization, certain shareholders of the Predecessor Fund who held shares directly with the Predecessor Fund and not through an intermediary had the Class A Shares, Class C Shares, Class I Shares, and Class N Shares of the Fund received in the merger automatically exchanged for Class D Shares of the Fund following the merger. If Class D Shares of the Fund had been available during periods prior to June 5, 2017, the performance shown may have been different because the Fund and the Predecessor Fund have different expenses. The performance shown for the periods following the Fund’s commencement of Class D Shares reflects the fees and expenses of Class D Shares, 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 table compares the Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more supplemental indices that have investment characteristics similar to those of the Fund. 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 (and the Predecessor Fund’s) past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future. Updated performance information is available at janushenderson.com/allfunds or by calling 1-800-525-3713.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	<span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;">The bar chart depicts the change in performance from year to year during the periods indicated. </span><span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;">The table compares the </span><span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;">Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more supplemental indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions.</span>
Performance Additional Market Index [Text]	rr_PerformanceAdditionalMarketIndex	<span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;">The table compares the </span><span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;">Fund’s average annual returns for the periods indicated to a broad-based securities market index, as well as to one or more supplemental indices that have investment characteristics similar to those of the Fund. All figures assume reinvestment of dividends and distributions.</span>
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	<span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;font-style:italic;">1-800-525-3713</span>
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	<span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;font-style:italic;">janushenderson.com/allfunds</span>
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	<span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;font-style:italic;">The Fund’s (and the Predecessor Fund’s) past performance (before and after taxes) does not necessarily indicate how the Fund will perform in the future.</span>
Bar Chart [Heading]	rr_BarChartHeading	Annual Total Returns for Class D Shares (calendar year-end)
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter:4th Quarter 202011.77%Worst Quarter:1st Quarter 2020– 17.86%
Year to Date Return, Label	rr_YearToDateReturnLabel	<span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;margin-left:3pt;">The Fund’s year-to-date return as of the calendar quarter ended </span><span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;">September 30, 2021 was 5.68%.</span>
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns (periods ended 12/31/20)
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	<span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;"> 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. </span>
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	<span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;">Actual after-tax returns depend on </span><span style="color:#000000;font-family:Times New Roman;font-size:9.50pt;">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-advantaged account, such as a 401(k) plan or an IRA.</span>
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	The Fund’s primary benchmark index is the MSCI World Index. The Fund also compares its performance to the 75% MSCI World / 25% Bloomberg Global Agg Credit (USD Hedged) Index. The indices are described below.•The MSCI World Index is designed to measure the equity market performance of developed market countries in North America, Europe, and the Asia/Pacific Region.•The 75% MSCI World / 25% Bloomberg Global Agg Credit (USD Hedged) Index is an internally-calculated, hypothetical combination of total returns from the MSCI World Index (75%) and the Bloomberg Global Aggregate Credit Index (USD Hedged) (25%).After-tax returns are calculated using distributions for the Predecessor Fund’s Class I Shares for the period prior to June 5, 2017. If Class D Shares of the Fund had been available during periods prior to June 5, 2017, the distributions used to calculate the after-tax returns may have been different. 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-advantaged account, such as a 401(k) plan or an IRA.
Class D Shares | Janus Henderson Dividend and Income Builder Fund | Class D
Risk Return Abstract	rr_RiskReturnAbstract
Management Fees	rr_ManagementFeesOverAssets	0.75%
Other Expenses	rr_OtherExpensesOverAssets	0.37%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.12%
Fee Waiver	rr_FeeWaiverOrReimbursementOverAssets	0.13%	[1]
Total Annual Fund Operating Expenses After Fee Waiver	rr_NetExpensesOverAssets	0.99%	[1]
1 Year	rr_ExpenseExampleYear01	$ 114
3 Years	rr_ExpenseExampleYear03	356
5 Years	rr_ExpenseExampleYear05	617
10 Years	rr_ExpenseExampleYear10	$ 1,363
2013	rr_AnnualReturn2013	20.71%
2014	rr_AnnualReturn2014	1.01%
2015	rr_AnnualReturn2015	1.59%
2016	rr_AnnualReturn2016	4.34%
2017	rr_AnnualReturn2017	17.62%
2018	rr_AnnualReturn2018	(9.13%)
2019	rr_AnnualReturn2019	18.71%
2020	rr_AnnualReturn2020	5.15%
Bar Chart, Year to Date Return, Date	rr_BarChartYearToDateReturnDate	Sep. 30, 2021
Bar Chart, Year to Date Return	rr_BarChartYearToDateReturn	5.68%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Dec. 31, 2020
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	11.77%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Mar. 31, 2020
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(17.86%)
Class D Shares | Janus Henderson Dividend and Income Builder Fund | Return Before Taxes | Class D
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	5.15%
5 Years	rr_AverageAnnualReturnYear05	6.84%
Since Inception	rr_AverageAnnualReturnSinceInception	7.55%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 01, 2012
Class D Shares | Janus Henderson Dividend and Income Builder Fund | Return After Taxes on Distributions | Class D
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	4.48%
5 Years	rr_AverageAnnualReturnYear05	6.15%
Since Inception	rr_AverageAnnualReturnSinceInception	6.76%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 01, 2012
Class D Shares | Janus Henderson Dividend and Income Builder Fund | Return After Taxes on Distributions and Sale of Fund Shares | Class D
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	3.75%
5 Years	rr_AverageAnnualReturnYear05	5.41%
Since Inception	rr_AverageAnnualReturnSinceInception	5.99%
Inception Date	rr_AverageAnnualReturnInceptionDate	Aug. 01, 2012
Class D Shares | Janus Henderson Dividend and Income Builder Fund | MSCI World Index (reflects no deduction for expenses, fees, or taxes, except foreign withholding taxes)
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	15.90%
5 Years	rr_AverageAnnualReturnYear05	12.19%
Since Inception	rr_AverageAnnualReturnSinceInception	11.68%
Class D Shares | Janus Henderson Dividend and Income Builder Fund | 75% MSCI World/25% Bloomberg Global Agg Credit (USD Hedged) Index (reflects no deduction for expenses, fees, or taxes, except foreign withholding taxes)
Risk Return Abstract	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	14.26%
5 Years	rr_AverageAnnualReturnYear05	10.79%
Since Inception	rr_AverageAnnualReturnSinceInception	10.04%

[1] The Adviser has contractually agreed to waive its investment advisory fee and/or reimburse operating expenses to the extent that the Fund’s total annual fund operating expenses (excluding shareholder servicing fees, such as transfer agency fees (including out-of-pocket costs), administrative services fees, brokerage commissions, interest, dividends, taxes, acquired fund fees and expenses, and extraordinary expenses) exceed 0.84% for at least a one-year period commencing on October 28, 2021. The contractual waiver may be terminated or modified prior to this date only at the discretion of the Board of Trustees.