Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	RS INVESTMENT TRUST
Prospectus Date	rr_ProspectusDate	May 01, 2013
Class Y Prospectus | RS Strategic Income Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	RS Strategic Income Fund
Objective [Heading]	rr_ObjectiveHeading	Investment Objectives
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	To seek high current income
Objective, Secondary [Text Block]	rr_ObjectiveSecondaryTextBlock	with a secondary objective of capital appreciation.
Expense [Heading]	rr_ExpenseHeading	Fees and Expenses of the Fund
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	The table below describes the fees and expenses that you may pay if you buy and hold shares of the Fund. No sales loads are imposed on Class Y shares.
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual Fund Operating Expenses (expenses are deducted from Fund assets as a percentage of average daily net assets)
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	April 30, 2014
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio Turnover
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The Fund pays transaction costs 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 for you if your 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 (not annualized) was 157% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	157.00%
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This Example is intended to help you compare the cost of investing in the Fund with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated, whether or not you redeem at the end of such periods. This Example also assumes that your investment earns a 5% return each year and that the Fund’s operating expenses remain the same as shown above. Although your actual costs may be higher or lower, based on these assumptions, your costs would be:
Strategy [Heading]	rr_StrategyHeading	Investments, Risks, and Performance Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Fund may invest in fixed-income obligations of any kind, including, by way of example, U.S. and foreign corporate investment-grade securities; U.S. government securities and securities of foreign governments and supranational entities; U.S. and foreign below investment grade bonds; and cash instruments. The Fund’s investment team allocates the Fund’s investments among these (and other) types of obligations based on its detailed analysis of market, economic, political, and other factors, and of the potential for the various obligations to provide high current income and/or capital appreciation. The Fund’s investment team selects specific investments for the Fund by considering a wide variety of factors, including yield, potential for appreciation in value, the credit quality of the issuer or collateral, maturity, and the degree of risk associated with a specific investment relative to the potential for favorable investment returns and to other investments. The Fund’s investment team may sell investments when it believes that they no longer offer attractive potential future returns compared to other investment opportunities or that they present undesirable risks, or in an attempt to limit losses on investments that may decline or have declined in value. The Fund may invest in investments of any maturity. The Fund may invest in securities of any quality, and may invest without limit in below investment grade securities or unrated securities considered by the Fund’s investment team to be of comparable quality, sometimes referred to as “high yield” or “junk” bonds. An investment will be considered to be below investment grade if it is rated Ba1 by Moody’s Investors Service, Inc. and BB+ by Standard & Poor’s Ratings Group, or lower or, if unrated, is considered by the Fund’s investment team to be of comparable quality. A below investment grade rating reflects a greater possibility that the issuer of an investment may be unable to make timely payments of interest and principal and thus default. If this happens, or is perceived as likely to happen, the value of that investment will usually be more volatile and is likely to fall. A default or expected default would likely also make it difficult for the Fund to sell an investment at a price approximating the value the Fund has previously placed on it. The Fund may invest in emerging markets debt. There is no limit on the amount of the Fund’s assets that may be invested in obligations of issuers in any country or group of countries. The Fund may invest in any type of debt instrument, including, for example, domestic or foreign corporate debt securities, securities issued or guaranteed by sovereign governments, their agencies, or instrumentalities, and mortgage-backed securities. The Fund may invest in “tax credit bonds” (including Build America Bonds, clean renewable energy bonds and qualified tax credit bonds) and tax-exempt bonds. The Fund may invest in convertible securities and warrants. The Fund may invest a substantial portion of its assets in mortgage-backed securities, including collateralized mortgage obligations, and other asset-backed securities. The Fund may invest in loans of any maturity and credit quality. If the Fund invests in loans, the Fund’s investment team may seek to avoid the receipt of material non-public information about the issuers of the loans being considered for purchase by the Fund, which may affect its ability to assess the loans as compared to investors that do receive such information. The Fund may enter into exchange-traded or over-the-counter derivatives transactions of any kind, such as futures contracts, options on futures, and swap contracts, including, for example, interest rate swaps and credit default swaps. The Fund also may enter into exchange-traded or over-the-counter foreign currency exchange transactions, including currency futures, forward, and option transactions. The Fund may enter into any of these transactions for a variety of purposes, including, but not limited to, hedging various risks such as credit risk, interest rate risk, currency risk, and liquidity risk; taking a net long or short position in certain investments or markets; providing liquidity in the Fund; equitizing cash; minimizing transaction costs; generating income; adjusting the Fund’s sensitivity to interest rate risk, currency risk, or other risk; replicating certain direct investments; and asset and sector allocation. In addition, as a substitute for investments directly in debt securities, the Fund may seek exposure to such debt securities through investments in exchange-traded funds.
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	You may lose money by investing in the Fund. The Fund may not achieve its investment objectives. The principal risks of investing in the Fund, which could adversely affect its net asset value and total return, are as follows. Debt Securities Risk The value of a debt security or other income-producing security changes in response to various factors, including, by way of example, market-related factors (such as changes in interest rates or changes in the risk appetite of investors generally) and changes in the actual or perceived ability of the issuer (or of issuers generally) to meet its (or their) obligations. High-yield/Junk Bond Risk Lower-quality debt securities can involve a substantially greater risk of default than higher quality debt securities, and their values can decline significantly over short periods of time. Lower-quality debt securities tend to be more sensitive to adverse news about the issuer, or the market or economy in general. Liquidity Risk Lack of a ready market or restrictions on resale may limit the ability of the Fund to sell a security at an advantageous time or price. In addition, the Fund, by itself or together with other accounts managed by Guardian Investor Services LLC, may hold a position in a security that is large relative to the typical trading volume for that security, which can make it difficult for the Fund to dispose of the position at an advantageous time or price. Derivatives Risk Derivative transactions can create investment leverage and may be highly volatile. It is possible that a derivative transaction will result in a loss greater than the principal amount invested, and the Fund may not be able to close out a derivative transaction at a favorable time or price. The counterparty to a derivatives contract may be unable or unwilling to make timely settlement payments, return the Fund’s margin, or otherwise honor its obligations. Mortgage- and Asset-backed Securities Risk During periods of falling interest rates, mortgage- and asset-backed securities may be called or prepaid, which may result in the Fund having to reinvest proceeds in other investments at a lower interest rate. During periods of rising interest rates, the average life of mortgage- and asset-backed securities may extend, which may lock in a below-market interest rate, increase the security’s duration, and reduce the value of the security. Enforcing rights against the underlying assets or collateral may be difficult, or the underlying assets or collateral may be insufficient if the issuer defaults. Foreign Securities Risk Foreign securities are subject to political, regulatory, and economic risks not present in domestic investments. In addition, when the Fund buys securities denominated in a foreign currency, there are special risks such as changes in currency exchange rates and the risk that a foreign government could regulate foreign exchange transactions. In addition, to the extent that investments are made in a limited number of countries, events in those countries will have a more significant impact on the Fund. Emerging Market Risk Risks of investing in emerging markets include greater political and economic instability, greater volatility in currency exchange rates, less developed securities markets, possible trade barriers, currency transfer restrictions, a more limited number of potential buyers, an emerging market country’s dependence on revenue from particular commodities or international aid, less governmental supervision and regulation, unavailability of currency hedging techniques, differences in auditing and financial reporting standards, and less developed legal systems. Municipal Obligations Risk Issuers, including governmental issuers, may be unable to pay their obligations as they come due. The values of municipal obligations that depend on a specific revenue source to fund their payment obligations may fluctuate as a result of changes in the cash flows generated by the revenue source or changes in the priority of the municipal obligation to receive the cash flows generated by the revenue source. In addition, changes in federal tax laws or the activity of an issuer may adversely affect the tax-exempt status of municipal obligations. Loss of tax-exempt status may cause interest received and distributed to shareholders by the Fund to be taxable and may result in a significant decline in the values of such municipal obligations. Currency Risk Investments in foreign securities are often denominated and traded in foreign currencies. The value of the Fund’s assets may be affected favorably or unfavorably by currency exchange rates, currency exchange control regulations, and restrictions or prohibitions on the repatriation of foreign currencies. To attempt to protect against changes in currency exchange rates, the Fund may, but will not necessarily, engage in forward foreign-currency exchange transactions. The use of foreign exchange transactions to reduce foreign-currency exposure can eliminate some or all of the benefit of an increase in the value of a foreign currency versus the U.S. dollar. Loan Risk Investments in loans are generally subject to the same risks as investments in other types of debt securities, including, in many cases, investments in high-yield/junk bonds. They may be difficult to value and may be illiquid. If the Fund holds a loan through another financial institution, or relies on a financial institution to administer the loan, its receipt of principal and interest on the loan may be subject to the credit risk of that financial institution. It is possible that any collateral securing a loan may be insufficient or unavailable to the Fund, and that the Fund’s rights to collateral may be limited by bankruptcy or insolvency laws. There may be limited public information available regarding the loan. Transactions in loans may settle on a delayed basis, and the Fund may not receive the proceeds from the sale of a loan for a substantial period of time after the sale. Portfolio Turnover Risk Frequent purchases and sales of portfolio securities may result in higher Fund expenses and may result in more significant distributions of short-term capital gains to investors, which are taxed as ordinary income. In recent periods, the Fund has experienced annual portfolio turnover in excess of 100% and may experience high portfolio turnover rates in the future. Credit Derivatives Risk The Fund may enter into credit derivatives, including credit default swaps and credit default index investments. The Fund may use these investments (i) as alternatives to direct long or short investment in a particular security, (ii) to adjust the Fund’s asset allocation or risk exposure, or (iii) for hedging purposes. The use by the Fund of credit default swaps may have the effect of creating a short position in a security. These investments can create investment leverage and may create additional investment risks that may subject the Fund to greater volatility than investments in more traditional securities.
Risk Lose Money [Text]	rr_RiskLoseMoney	You may lose money by investing in the Fund.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Fund Performance
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The bar chart and table provide some indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year to year and by showing how the Fund’s average annual returns for 1 year and since inception compare with those of a broad measure of market performance. The Fund’s past performance (before and after taxes) is not an indication of future performance. Updated performance information for the Fund is available at www.rsinvestments.com or by calling 800-766-3863.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart and table provide some indication of the risks of investing in the Fund by showing changes in the Fund’s performance from year to year and by showing how the Fund’s average annual returns for 1 year and since inception compare with those of a broad measure of market performance.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	800-766-3863
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	www.rsinvestments.com
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund’s past performance (before and after taxes) is not an indication of future performance.
Bar Chart [Heading]	rr_BarChartHeading	Annual Total Return for Class Y Shares (calendar year-end)
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Best Quarter  Third Quarter 2010  4.12% Worst Quarter  Third Quarter 2011  -0.68%
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 historical 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 an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(k) plans or individual retirement accounts.
Class Y Prospectus | RS Strategic Income Fund | Class Y
Risk/Return:	rr_RiskReturnAbstract
Management Fees	rr_ManagementFeesOverAssets	0.60%
Distribution (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets
Other Expenses	rr_OtherExpensesOverAssets	0.30%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.90%	[1]
Fee Waiver/Expense Reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.31%)	[1]
Total Annual Fund Operating Expenses After Fee Waiver/Expense Reimbursement	rr_NetExpensesOverAssets	0.59%	[1]
1 Year	rr_ExpenseExampleYear01	60
3 Years	rr_ExpenseExampleYear03	256
5 Years	rr_ExpenseExampleYear05	468
10 Years	rr_ExpenseExampleYear10	1,079
1 Year	rr_ExpenseExampleNoRedemptionYear01	60
3 Years	rr_ExpenseExampleNoRedemptionYear03	256
5 Years	rr_ExpenseExampleNoRedemptionYear05	468
10 Years	rr_ExpenseExampleNoRedemptionYear10	1,079
2010	rr_AnnualReturn2010	8.95%
2011	rr_AnnualReturn2011	5.82%
2012	rr_AnnualReturn2012	8.93%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Best Quarter
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2010
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	4.12%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Worst Quarter
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Sep. 30, 2011
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(0.68%)
1 Year	rr_AverageAnnualReturnYear01	8.93%
Since Inception	rr_AverageAnnualReturnSinceInception	7.89%
Inception Date	rr_AverageAnnualReturnInceptionDate	Dec. 31, 2009
Class Y Prospectus | RS Strategic Income Fund | Return After Taxes on Distributions | Class Y
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	7.06%
Since Inception	rr_AverageAnnualReturnSinceInception	5.91%
Inception Date	rr_AverageAnnualReturnInceptionDate	Dec. 31, 2009
Class Y Prospectus | RS Strategic Income Fund | Return After Taxes on Distributions and Sale of Fund Shares | Class Y
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	5.86%
Since Inception	rr_AverageAnnualReturnSinceInception	5.60%
Inception Date	rr_AverageAnnualReturnInceptionDate	Dec. 31, 2009
Class Y Prospectus | RS Strategic Income Fund | Barclays U.S. Aggregate Bond Index (reflects no deductions for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	4.21%
Since Inception	rr_AverageAnnualReturnSinceInception	6.19%
Inception Date	rr_AverageAnnualReturnInceptionDate	Dec. 31, 2009

[1] RS Investments has contractually agreed to limit the Total Annual Fund Operating Expenses for Class Y Shares so that Class Y benefits from a level of reimbursement (as expressed in basis points) that is the same as the level of reimbursement for Class A shares during the period. This expense limitation will continue through April 30, 2014 and cannot be terminated by RS Investments prior to that date without the action or consent of the Fund's Board of Trustees.