XML 21 R38.htm IDEA: XBRL DOCUMENT v3.8.0.1
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Registrant Name dei_EntityRegistrantName DEUTSCHE INVESTMENT TRUST
Prospectus Date rr_ProspectusDate Feb. 01, 2018
Deutsche Small Cap Growth Fund  
Risk/Return: rr_RiskReturnAbstract  
Risk/Return [Heading] rr_RiskReturnHeading Deutsche Small Cap Growth Fund
Objective [Heading] rr_ObjectiveHeading

Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock

The fund seeks long-term capital growth.
Expense [Heading] rr_ExpenseHeading

Fees and Expenses of the Fund
Expense Narrative [Text Block] rr_ExpenseNarrativeTextBlock

These are the fees and expenses you may pay when you buy and hold shares. You may qualify for sales charge discounts if you and your immediate family invest, or agree to invest in the future, at least $50,000 in Class A shares in Deutsche funds or if you invest at least $250,000 in Class T shares in the fund. More information about these and other discounts and waivers is available from your financial advisor and in Choosing a Share Class (p. 36), Sales Charge Waivers and Discounts Available Through Intermediaries (Appendix B, p. 95) and Purchase and Redemption of Shares in the fund's Statement of Additional Information (SAI) (p. II-16).
Shareholder Fees Caption [Text] rr_ShareholderFeesCaption SHAREHOLDER FEES (paid directly from your investment)
Operating Expenses Caption [Text] rr_OperatingExpensesCaption ANNUAL FUND OPERATING EXPENSES
(expenses that you pay each year as a % of the value of your investment)
Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination September 30, 2019
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 may indicate higher transaction costs and may mean higher taxes if you are investing in a taxable account. These costs are not reflected in annual fund operating expenses or in the expense example, and can affect the fund's performance.

Portfolio turnover rate for fiscal year 2017: 32%.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 32.00%
Expense Footnotes [Text Block] rr_ExpenseFootnotesTextBlock

The Advisor has contractually agreed through September 30, 2019 to waive its fees and/or reimburse fund expenses to the extent necessary to maintain the fund's total annual operating expenses (excluding certain expenses such as extraordinary expenses, taxes, brokerage and interest expenses) at ratios no higher than 1.21%, 1.21%, 1.96%, 1.46%, 0.95%, 0.95% and 0.95% for Class A, Class T, Class C, Class R, Class R6, Institutional Class and Class S, respectively. The agreement may only be terminated with the consent of the fund's Board.
Expense Breakpoint Discounts [Text] rr_ExpenseBreakpointDiscounts You may qualify for sales charge discounts if you and your immediate family invest, or agree to invest in the future, at least $50,000 in Class A shares in Deutsche funds or if you invest at least $250,000 in Class T shares in the fund.
Expense Breakpoint, Minimum Investment Required [Amount] rr_ExpenseBreakpointMinimumInvestmentRequiredAmount $ 50,000
Other Expenses, New Fund, Based on Estimates [Text] rr_OtherExpensesNewFundBasedOnEstimates

1 "Other expenses" for Class T are based on estimated amounts for the current fiscal year.

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 cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the fund's operating expenses (including one year of capped expenses in each period) remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Expense Example, No Redemption Narrative [Text Block] rr_ExpenseExampleNoRedemptionNarrativeTextBlock You would pay the following expenses if you did not redeem your shares:
Strategy [Heading] rr_StrategyHeading

Principal Investment Strategy
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock

Main investments. Under normal circumstances, the fund invests at least 80% of its assets, determined at the time of purchase, in stocks and other securities with equity characteristics of US smaller capitalization companies. For purposes of this 80% investment limitation, the term assets is defined as net assets, plus the amount of any borrowings for investment purposes, and the small capitalization equity universe is defined as the bottom 20% of the total domestic equity market capitalization (at the time of initial investment), using a minimum market capitalization of $10 million. As of December 31, 2017, companies in which the fund typically invests have a market capitalization range of between $14 million and $12.1 billion. The fund may also invest in other types of equity securities such as preferred stocks or convertible securities. The fund may invest up to 20% of its assets in the stocks of non-US companies, including those in emerging markets, and large capitalization stocks.

Management process. In choosing stocks, portfolio management focuses on individual security selection rather than industry selection. Portfolio management uses an active process that combines financial analysis with company visits to evaluate management and strategies.

Company research is significant to the investment process. Portfolio management uses a "bottom-up" approach to picking securities, focusing on stocks that it believes have superior growth prospects and above average intermediate to long-term performance potential.

Portfolio management emphasizes individual selection of small company stocks across all economic sectors, early in their growth cycles and which portfolio management believes to have the potential to be the blue chips of the future. Portfolio management generally seeks companies it believes have a leading or dominant position in their niche markets, a high rate of return on invested capital and the ability to finance a major part of future growth from internal sources. Portfolio management also looks for estimated above-average growth in revenues and earnings and a balance sheet that portfolio management believes can support this growth potential with sufficient working capital and manageable levels of debt.

Portfolio management follows a disciplined selling process that seeks to lessen risk, and will normally sell a stock when its price reaches portfolio management's expectations, portfolio management believes there is a material change in the company's fundamentals, other investments offer better opportunities or in an effort to readjust the weighted average market capitalization of the fund.

Securities Lending. The fund may lend securities (up to one-third of total assets) to approved institutions.

Risk [Heading] rr_RiskHeading

Main Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock

There are several risk factors that could hurt the fund's performance, cause you to lose money or cause the fund's performance to trail that of other investments. The fund may not achieve its investment objective, and is not intended to be a complete investment program. An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.

Stock market risk. When stock prices fall, you should expect the value of your investment to fall as well. Stock prices can be hurt by poor management on the part of the stock's issuer, shrinking product demand and other business risks. These may affect single companies as well as groups of companies. The market as a whole may not favor the types of investments the fund makes, which could adversely affect a stock's price, regardless of how well the company performs, or the fund's ability to sell a stock at an attractive price. There is a chance that stock prices overall will decline because stock markets tend to move in cycles, with periods of rising and falling prices. Events in the U.S. and global financial markets, including actions taken by the U.S. Federal Reserve or foreign central banks to stimulate or stabilize economic growth, may at times result in unusually high market volatility which could negatively affect performance. To the extent the fund invests in a particular capitalization or sector, the fund's performance may be affected by the general performance of that particular capitalization or sector.

Small company risk. Small company stocks tend to be more volatile than medium-sized or large company stocks. Because stock analysts are less likely to follow small companies, less information about them is available to investors. Industry-wide reversals may have a greater impact on small companies, since they may lack the financial resources of larger companies. Small company stocks are typically less liquid than large company stocks.

Growth investing risk. As a category, growth stocks may underperform value stocks (and the stock market as a whole) over any period of time. Because the prices of growth stocks are based largely on the expectation of future earnings, growth stock prices can decline rapidly and significantly in reaction to negative news about such factors as earnings, the economy, political developments, or other news.

Security selection risk. The securities in the fund's portfolio may decline in value. Portfolio management could be wrong in its analysis of industries, companies, economic trends, the relative attractiveness of different securities or other matters.

Foreign investment risk. The fund faces the risks inherent in foreign investing. Adverse political, economic or social developments could undermine the value of the fund's investments or prevent the fund from realizing the full value of its investments. In June 2016, citizens of the United Kingdom approved a referendum to leave the European Union (EU) and in March 2017, the United Kingdom initiated its withdrawal from the EU, which is expected to take place by March 2019. Significant uncertainty exists regarding the United Kingdom's anticipated withdrawal from the EU and any adverse economic and political effects such withdrawal may have on the United Kingdom, other EU countries and the global economy.

Financial reporting standards for companies based in foreign markets differ from those in the US. Additionally, foreign securities markets generally are smaller and less liquid than US markets. To the extent that the fund invests in non-US dollar denominated foreign securities, changes in currency exchange rates may affect the US dollar value of foreign securities or the income or gain received on these securities.

Emerging markets risk. Foreign investment risks are greater in emerging markets than in developed markets. Investments in emerging markets are often considered speculative.

Focus risk. To the extent that the fund focuses its investments in particular industries, asset classes or sectors of the economy, any market price movements, regulatory or technological changes, or economic conditions affecting companies in those industries, asset classes or sectors may have a significant impact on the fund's performance.

Securities lending risk. Any decline in the value of a portfolio security that occurs while the security is out on loan is borne by the fund and will adversely affect performance. Also, there may be delays in recovery of securities loaned or even a loss of rights in the collateral should the borrower of the securities fail financially while holding the security.

Liquidity risk. In certain situations, it may be difficult or impossible to sell an investment and/or the fund may sell certain investments at a price or time that is not advantageous in order to meet redemption requests or other cash needs. Unusual market conditions, such as an unusually high volume of redemptions or other similar conditions could increase liquidity risk for the fund.

Pricing risk. If market conditions make it difficult to value some investments, the fund may value these investments using more subjective methods, such as fair value pricing. In such cases, the value determined for an investment could be different from the value realized upon such investment's sale. As a result, you could pay more than the market value when buying fund shares or receive less than the market value when selling fund shares.

Operational and technology risk. Cyber-attacks, disruptions, or failures that affect the fund's service providers or counterparties, issuers of securities held by the fund, or other market participants may adversely affect the fund and its shareholders, including by causing losses for the fund or impairing fund operations.
Risk Lose Money [Text] rr_RiskLoseMoney There are several risk factors that could hurt the fund's performance, cause you to lose money or cause the fund's performance to trail that of other investments.
Risk Not Insured Depository Institution [Text] rr_RiskNotInsuredDepositoryInstitution An investment in the fund is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency.
Bar Chart and Performance Table [Heading] rr_BarChartAndPerformanceTableHeading

Past Performance
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock

How a fund's returns vary from year to year can give an idea of its risk; so can comparing fund performance to overall market performance (as measured by an appropriate market index). Past performance may not indicate future results. All performance figures below assume that dividends and distributions were reinvested. For more recent performance figures, go to deutschefunds.com (the Web site does not form a part of this prospectus) or call the phone number included in this prospectus.

Class T is a new class of shares and as of the date of this prospectus had not commenced investment operations. The performance figures for Class T shares are based on the historical performance of the fund's Institutional Class shares adjusted to reflect the higher expenses and applicable sales charges of Class T.

Performance Information Illustrates Variability of Returns [Text] rr_PerformanceInformationIllustratesVariabilityOfReturns How a fund's returns vary from year to year can give an idea of its risk; so can comparing fund performance to overall market performance (as measured by an appropriate market index).
Performance Availability Website Address [Text] rr_PerformanceAvailabilityWebSiteAddress deutschefunds.com
Performance Past Does Not Indicate Future [Text] rr_PerformancePastDoesNotIndicateFuture Past performance may not indicate future results.
Bar Chart [Heading] rr_BarChartHeading CALENDAR YEAR TOTAL RETURNS (%) (Class A)
Bar Chart Narrative [Text Block] rr_BarChartNarrativeTextBlock These year-by-year returns do not include sales charges, if any, and would be lower if they did. Returns for other classes were different and are not shown here.
Bar Chart Does Not Reflect Sales Loads [Text] rr_BarChartDoesNotReflectSalesLoads These year-by-year returns do not include sales charges, if any, and would be lower if they did.
Bar Chart Closing [Text Block] rr_BarChartClosingTextBlock
Returns Period ending
Best Quarter 25.24% June 30, 2009
Worst Quarter -32.52% December 31, 2008

Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns
(For periods ended 12/31/2017 expressed as a %)
Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate After-tax returns (which are shown only for Class A and would be different for other classes) reflect the historical highest individual federal income tax rates, but do not reflect any state or local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred After-tax returns are not relevant to shares held in an IRA, 401(k) or other tax-advantaged investment plan.
Performance Table One Class of after Tax Shown [Text] rr_PerformanceTableOneClassOfAfterTaxShown After-tax returns (which are shown only for Class A and would be different for other classes)
Performance Table Narrative rr_PerformanceTableNarrativeTextBlock After-tax returns (which are shown only for Class A and would be different for other classes) reflect the historical highest individual federal income tax rates, but do not reflect any state or local taxes. Your actual after-tax returns may be different. After-tax returns are not relevant to shares held in an IRA, 401(k) or other tax-advantaged investment plan.
Deutsche Small Cap Growth Fund | Class A  
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases, as % of offering price rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice 5.75%
Maximum deferred sales charge (load), as % of redemption proceeds rr_MaximumDeferredSalesChargeOverOther none
Account Maintenance Fee (annually, for fund account balances below $10,000 and subject to certain exceptions) rr_MaximumAccountFee $ 20
Management fee rr_ManagementFeesOverAssets 0.65%
Distribution/service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets 0.24%
Other expenses rr_OtherExpensesOverAssets 0.52% [1]
Total annual fund operating expenses rr_ExpensesOverAssets 1.41%
Fee waiver/expense reimbursement rr_FeeWaiverOrReimbursementOverAssets 0.20%
Total annual fund operating expenses after fee waiver/expense reimbursement rr_NetExpensesOverAssets 1.21%
1 Year rr_ExpenseExampleYear01 $ 691
3 Years rr_ExpenseExampleYear03 977
5 Years rr_ExpenseExampleYear05 1,284
10 Years rr_ExpenseExampleYear10 2,152
1 Year rr_ExpenseExampleNoRedemptionYear01 691
3 Years rr_ExpenseExampleNoRedemptionYear03 977
5 Years rr_ExpenseExampleNoRedemptionYear05 1,284
10 Years rr_ExpenseExampleNoRedemptionYear10 $ 2,152
2008 rr_AnnualReturn2008 (50.39%)
2009 rr_AnnualReturn2009 39.93%
2010 rr_AnnualReturn2010 29.69%
2011 rr_AnnualReturn2011 2.67%
2012 rr_AnnualReturn2012 11.08%
2013 rr_AnnualReturn2013 44.19%
2014 rr_AnnualReturn2014 2.44%
2015 rr_AnnualReturn2015 (2.51%)
2016 rr_AnnualReturn2016 8.56%
2017 rr_AnnualReturn2017 20.79%
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Best Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Jun. 30, 2009
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 25.24%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Worst Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2008
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (32.52%)
Deutsche Small Cap Growth Fund | Class T  
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases, as % of offering price rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice 2.50%
Maximum deferred sales charge (load), as % of redemption proceeds rr_MaximumDeferredSalesChargeOverOther none
Account Maintenance Fee (annually, for fund account balances below $10,000 and subject to certain exceptions) rr_MaximumAccountFee none
Management fee rr_ManagementFeesOverAssets 0.65%
Distribution/service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other expenses rr_OtherExpensesOverAssets 0.47% [1]
Total annual fund operating expenses rr_ExpensesOverAssets 1.37%
Fee waiver/expense reimbursement rr_FeeWaiverOrReimbursementOverAssets 0.16%
Total annual fund operating expenses after fee waiver/expense reimbursement rr_NetExpensesOverAssets 1.21%
1 Year rr_ExpenseExampleYear01 $ 370
3 Years rr_ExpenseExampleYear03 658
5 Years rr_ExpenseExampleYear05 966
10 Years rr_ExpenseExampleYear10 1,842
1 Year rr_ExpenseExampleNoRedemptionYear01 370
3 Years rr_ExpenseExampleNoRedemptionYear03 658
5 Years rr_ExpenseExampleNoRedemptionYear05 966
10 Years rr_ExpenseExampleNoRedemptionYear10 $ 1,842
Deutsche Small Cap Growth Fund | Class C  
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases, as % of offering price rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum deferred sales charge (load), as % of redemption proceeds rr_MaximumDeferredSalesChargeOverOther 1.00%
Account Maintenance Fee (annually, for fund account balances below $10,000 and subject to certain exceptions) rr_MaximumAccountFee $ 20
Management fee rr_ManagementFeesOverAssets 0.65%
Distribution/service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets 1.00%
Other expenses rr_OtherExpensesOverAssets 0.49% [1]
Total annual fund operating expenses rr_ExpensesOverAssets 2.14%
Fee waiver/expense reimbursement rr_FeeWaiverOrReimbursementOverAssets 0.18%
Total annual fund operating expenses after fee waiver/expense reimbursement rr_NetExpensesOverAssets 1.96%
1 Year rr_ExpenseExampleYear01 $ 299
3 Years rr_ExpenseExampleYear03 653
5 Years rr_ExpenseExampleYear05 1,133
10 Years rr_ExpenseExampleYear10 2,458
1 Year rr_ExpenseExampleNoRedemptionYear01 199
3 Years rr_ExpenseExampleNoRedemptionYear03 653
5 Years rr_ExpenseExampleNoRedemptionYear05 1,133
10 Years rr_ExpenseExampleNoRedemptionYear10 $ 2,458
Deutsche Small Cap Growth Fund | Class R  
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases, as % of offering price rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum deferred sales charge (load), as % of redemption proceeds rr_MaximumDeferredSalesChargeOverOther none
Account Maintenance Fee (annually, for fund account balances below $10,000 and subject to certain exceptions) rr_MaximumAccountFee none
Management fee rr_ManagementFeesOverAssets 0.65%
Distribution/service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets 0.50%
Other expenses rr_OtherExpensesOverAssets 0.58% [1]
Total annual fund operating expenses rr_ExpensesOverAssets 1.73%
Fee waiver/expense reimbursement rr_FeeWaiverOrReimbursementOverAssets 0.27%
Total annual fund operating expenses after fee waiver/expense reimbursement rr_NetExpensesOverAssets 1.46%
1 Year rr_ExpenseExampleYear01 $ 149
3 Years rr_ExpenseExampleYear03 519
5 Years rr_ExpenseExampleYear05 913
10 Years rr_ExpenseExampleYear10 2,019
1 Year rr_ExpenseExampleNoRedemptionYear01 149
3 Years rr_ExpenseExampleNoRedemptionYear03 519
5 Years rr_ExpenseExampleNoRedemptionYear05 913
10 Years rr_ExpenseExampleNoRedemptionYear10 $ 2,019
Deutsche Small Cap Growth Fund | Class R6  
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases, as % of offering price rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum deferred sales charge (load), as % of redemption proceeds rr_MaximumDeferredSalesChargeOverOther none
Account Maintenance Fee (annually, for fund account balances below $10,000 and subject to certain exceptions) rr_MaximumAccountFee none
Management fee rr_ManagementFeesOverAssets 0.65%
Distribution/service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.33% [1]
Total annual fund operating expenses rr_ExpensesOverAssets 0.98%
Fee waiver/expense reimbursement rr_FeeWaiverOrReimbursementOverAssets 0.03%
Total annual fund operating expenses after fee waiver/expense reimbursement rr_NetExpensesOverAssets 0.95%
1 Year rr_ExpenseExampleYear01 $ 97
3 Years rr_ExpenseExampleYear03 309
5 Years rr_ExpenseExampleYear05 539
10 Years rr_ExpenseExampleYear10 1,199
1 Year rr_ExpenseExampleNoRedemptionYear01 97
3 Years rr_ExpenseExampleNoRedemptionYear03 309
5 Years rr_ExpenseExampleNoRedemptionYear05 539
10 Years rr_ExpenseExampleNoRedemptionYear10 $ 1,199
Deutsche Small Cap Growth Fund | INST Class  
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases, as % of offering price rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum deferred sales charge (load), as % of redemption proceeds rr_MaximumDeferredSalesChargeOverOther none
Account Maintenance Fee (annually, for fund account balances below $10,000 and subject to certain exceptions) rr_MaximumAccountFee none
Management fee rr_ManagementFeesOverAssets 0.65%
Distribution/service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.37% [1]
Total annual fund operating expenses rr_ExpensesOverAssets 1.02%
Fee waiver/expense reimbursement rr_FeeWaiverOrReimbursementOverAssets 0.07%
Total annual fund operating expenses after fee waiver/expense reimbursement rr_NetExpensesOverAssets 0.95%
1 Year rr_ExpenseExampleYear01 $ 97
3 Years rr_ExpenseExampleYear03 318
5 Years rr_ExpenseExampleYear05 556
10 Years rr_ExpenseExampleYear10 1,241
1 Year rr_ExpenseExampleNoRedemptionYear01 97
3 Years rr_ExpenseExampleNoRedemptionYear03 318
5 Years rr_ExpenseExampleNoRedemptionYear05 556
10 Years rr_ExpenseExampleNoRedemptionYear10 $ 1,241
Deutsche Small Cap Growth Fund | Class S  
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases, as % of offering price rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum deferred sales charge (load), as % of redemption proceeds rr_MaximumDeferredSalesChargeOverOther none
Account Maintenance Fee (annually, for fund account balances below $10,000 and subject to certain exceptions) rr_MaximumAccountFee $ 20
Management fee rr_ManagementFeesOverAssets 0.65%
Distribution/service (12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.49% [1]
Total annual fund operating expenses rr_ExpensesOverAssets 1.14%
Fee waiver/expense reimbursement rr_FeeWaiverOrReimbursementOverAssets 0.19%
Total annual fund operating expenses after fee waiver/expense reimbursement rr_NetExpensesOverAssets 0.95%
1 Year rr_ExpenseExampleYear01 $ 97
3 Years rr_ExpenseExampleYear03 343
5 Years rr_ExpenseExampleYear05 609
10 Years rr_ExpenseExampleYear10 1,369
1 Year rr_ExpenseExampleNoRedemptionYear01 97
3 Years rr_ExpenseExampleNoRedemptionYear03 343
5 Years rr_ExpenseExampleNoRedemptionYear05 609
10 Years rr_ExpenseExampleNoRedemptionYear10 $ 1,369
Deutsche Small Cap Growth Fund | before tax | Class A  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 13.84%
5 Years rr_AverageAnnualReturnYear05 12.22%
10 Years rr_AverageAnnualReturnYear10 6.22%
Class Inception rr_AverageAnnualReturnInceptionDate Jun. 28, 2002
Deutsche Small Cap Growth Fund | before tax | Class T  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 17.60%
5 Years rr_AverageAnnualReturnYear05 12.92%
10 Years rr_AverageAnnualReturnYear10 6.54%
Class Inception rr_AverageAnnualReturnInceptionDate Feb. 01, 2017
Deutsche Small Cap Growth Fund | before tax | Class C  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 19.86%
5 Years rr_AverageAnnualReturnYear05 12.70%
10 Years rr_AverageAnnualReturnYear10 6.04%
Class Inception rr_AverageAnnualReturnInceptionDate Jun. 28, 2002
Deutsche Small Cap Growth Fund | before tax | Class R  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 20.40%
5 Years rr_AverageAnnualReturnYear05 13.27%
Since Inception rr_AverageAnnualReturnSinceInception 11.56%
Class Inception rr_AverageAnnualReturnInceptionDate May 01, 2012
Deutsche Small Cap Growth Fund | before tax | Class R6  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 21.06%
Since Inception rr_AverageAnnualReturnSinceInception 8.86%
Class Inception rr_AverageAnnualReturnInceptionDate Aug. 25, 2014
Deutsche Small Cap Growth Fund | before tax | INST Class  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 21.05%
5 Years rr_AverageAnnualReturnYear05 13.90%
10 Years rr_AverageAnnualReturnYear10 7.20%
Class Inception rr_AverageAnnualReturnInceptionDate Dec. 20, 2004
Deutsche Small Cap Growth Fund | before tax | Class S  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 21.04%
5 Years rr_AverageAnnualReturnYear05 13.84%
10 Years rr_AverageAnnualReturnYear10 7.11%
Class Inception rr_AverageAnnualReturnInceptionDate Dec. 20, 2004
Deutsche Small Cap Growth Fund | After tax on distributions | Class A  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 12.69%
5 Years rr_AverageAnnualReturnYear05 10.78%
10 Years rr_AverageAnnualReturnYear10 5.48%
Deutsche Small Cap Growth Fund | After tax on distributions and sale of fund shares | Class A  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 8.80%
5 Years rr_AverageAnnualReturnYear05 9.74%
10 Years rr_AverageAnnualReturnYear10 4.97%
Deutsche Small Cap Growth Fund | Russell 2000® Growth Index (reflects no deduction for fees, expenses or taxes) | Class R  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 22.17%
5 Years rr_AverageAnnualReturnYear05 15.21%
Since Inception rr_AverageAnnualReturnSinceInception 13.87%
Deutsche Small Cap Growth Fund | Russell 2000® Growth Index (reflects no deduction for fees, expenses or taxes) | Class R6  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 22.17%
Since Inception rr_AverageAnnualReturnSinceInception 11.04%
Deutsche Small Cap Growth Fund | Russell 2000® Growth Index (reflects no deduction for fees, expenses or taxes) | Class S  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 22.17%
5 Years rr_AverageAnnualReturnYear05 15.21%
10 Years rr_AverageAnnualReturnYear10 9.19%
[1] "Other expenses" for Class T are based on estimated amounts for the current fiscal year.