Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	NUVEEN INVESTMENT FUNDS INC
Prospectus Date	rr_ProspectusDate	Apr. 30, 2013
Nuveen Real Estate Securities Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	Nuveen Real Estate Securities Fund
Objective [Heading]	rr_ObjectiveHeading	Investment Objective
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The investment objective of the Fund is to provide above average current income and long-term capital appreciation.
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. 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 Nuveen Mutual Funds. More information about these and other discounts, as well as eligibility requirements for each share class, is available from your financial advisor and in “What Share Classes We Offer” on page 15 of the Fund’s prospectus, “How to Reduce Your Sales Charge” on page 18 of the prospectus and “Purchase and Redemption of Fund Shares” on page S-57 of the Fund’s statement of additional information.
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 76% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	76.00%
Expenses Deferred Charges [Text Block]	rr_ExpensesDeferredChargesTextBlock	The contingent deferred sales charge (“CDSC”) on Class B shares declines over a six-year period from purchase. The CDSC on Class C shares applies only to redemptions within 12 months of purchase.
Expense Breakpoint Discounts [Text]	rr_ExpenseBreakpointDiscounts	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 Nuveen Mutual Funds.
Expense Breakpoint, Minimum Investment Required [Amount]	rr_ExpenseBreakpointMinimumInvestmentRequiredAmount	50,000
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	The following 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 either redeem or do not redeem your shares at the end of a period. 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 by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Redemption
Expense Example, No Redemption, By Year, Caption [Text]	rr_ExpenseExampleNoRedemptionByYearCaption	No Redemption
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	Under normal market conditions, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in income-producing common stocks of publicly traded companies engaged in the real estate industry. These companies derive at least 50% of their revenues or profits from the ownership, construction, management, financing or sale of real estate, or have at least 50% of the fair market value of their assets invested in real estate. The Fund's sub-adviser will select companies that it believes exhibit strong management teams, a strong competitive position, above average growth in revenues and a sound balance sheet. These companies may be of any market capitalization, including small- and mid-capitalization companies. The sub-adviser will generally sell a stock if the stock hits its price target, the company's fundamentals or competitive position significantly deteriorate, or if a better alternative exists in the marketplace. A majority of the Fund's total assets will be invested in real estate investment trusts ("REITs"). REITs are publicly traded corporations or trusts that invest in residential or commercial real estate. REITs generally can be divided into the following three types: Equity REITs, which invest the majority of their assets directly in real property and derive their income primarily from rents and capital gains or real estate appreciation. Mortgage REITs, which invest the majority of their assets in real estate mortgage loans and derive their income primarily from interest payments. Hybrid REITs, which combine the characteristics of equity REITs and mortgage REITs. The Fund expects to emphasize investments in equity REITs, although it may invest in all three kinds of REITs. The Fund may invest up to 15% of its total assets in non-dollar denominated equity securities of non-U.S. issuers. In addition, the Fund may invest up to 25% of its assets, collectively, in non-dollar denominated equity securities of non-U.S. issuers and in dollar-denominated equity securities of non-U.S. issuers that are either listed on a U.S. stock exchange or represented by depositary receipts that may or may not be sponsored by a domestic bank. Up to 15% of the Fund's total assets may be invested in equity securities of emerging market issuers. A country is considered to be an "emerging market" if it is defined as such by Morgan Stanley Capital International Inc. The Fund may utilize derivatives, including options, futures contracts, options on futures contracts, and forward foreign currency exchange contracts. The Fund may use these derivatives to manage market or business risk, enhance the Fund's return, or hedge against adverse movements in currency exchange rates.
Strategy Portfolio Concentration [Text]	rr_StrategyPortfolioConcentration	Under normal market conditions, the Fund invests at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in income-producing common stocks of publicly traded companies engaged in the real estate industry. These companies derive at least 50% of their revenues or profits from the ownership, construction, management, financing or sale of real estate, or have at least 50% of the fair market value of their assets invested in real estate.
Risk [Heading]	rr_RiskHeading	Principal Risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	The value of your investment in this Fund will change daily, which means you could lose money. 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 government agency. The principal risks of investing in the Fund include: Derivatives Risk—The use of options, futures contracts, options on futures contracts and forward foreign currency exchange contracts involves additional risks, such as liquidity, interest rate, counterparty, market, credit and management risks, and transaction costs which could leave the Fund in a worse position than if it had not used these instruments. Derivatives may entail investment exposures that are greater than their cost would suggest. As a result, a small investment in derivatives could have a large impact on performance. Recent legislation requires the development of a new regulatory framework for the derivatives market. The impact of the new regulations is still unknown, but has the potential to increase the costs of using derivatives, may limit the availability of some forms of derivatives or the Fund's ability to use derivatives, and may adversely affect the performance of some derivative instruments used by the Fund as well as the Fund's ability to pursue its investment objective through the use of such instruments. Equity Security Risk—Equity securities may decline significantly in price over short or extended periods of time, and such declines may occur in the equity market as a whole, or they may occur in only a particular country, company, industry, or sector of the market. Non-U.S./Emerging Markets Risk—Non-U.S. issuers or U.S. issuers with significant non-U.S. operations may be subject to risks in addition to those of issuers located in or that principally operate in the United States as a result of, among other things, political, social and economic developments abroad and different legal, regulatory and tax environments. These additional risks may be heightened for securities of issuers located in, or with significant operations in, emerging market countries. Also, changes in currency exchange rates may affect the Fund's net asset value, the value of dividends and interest earned, and gains and losses realized on the sale of securities. Real Estate Investment Risk—The real estate industry has been subject to substantial fluctuations and declines on a local, regional and national basis in the past and may continue to be in the future. Also, the value of a REIT can be hurt by economic downturns or by changes in real estate values, rents, property taxes, interest rates, tax treatment, regulations, or the legal structure of the REIT. Smaller Company Risk—Small-cap stocks involve substantial risk. Prices of small-cap stocks may be subject to more abrupt or erratic movements, and to wider fluctuations, than stock prices of larger, more established companies or the market averages in general. It may be difficult to sell small-cap stocks at the desired time and price. While mid-cap stocks may be slightly less volatile than small-cap stocks, they still involve similar risks.
Risk Lose Money [Text]	rr_RiskLoseMoney	The value of your investment in this Fund will change daily, which means you could lose money.
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 government agency.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Fund Performance
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The following bar chart and table provide some indication of the potential risks of investing in the Fund. The Fund’s past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future. Updated performance information is available at www.nuveen.com/performance or by calling (800) 257-8787.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The bar chart below shows the variability of the Fund's performance from year to year for Class A shares.
Performance One Year or Less [Text]	rr_PerformanceOneYearOrLess	Performance is not shown for Class R6 shares, which have not been offered for a full calendar year.
Performance Availability Phone [Text]	rr_PerformanceAvailabilityPhone	(800) 257-8787
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	www.nuveen.com/performance
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.
Bar Chart [Heading]	rr_BarChartHeading	Class A Annual Total Return
Bar Chart Narrative [Text Block]	rr_BarChartNarrativeTextBlock	The bar chart below shows the variability of the Fund’s performance from year to year for Class A shares. The performance of the other share classes will differ due to their different expense structures. The bar chart and highest/lowest quarterly returns that follow do not reflect sales charges, and if these charges were reflected, the returns would be less than those shown.
Bar Chart Does Not Reflect Sales Loads [Text]	rr_BarChartDoesNotReflectSalesLoads	The bar chart and highest/lowest quarterly returns that follow do not reflect sales charges, and if these charges were reflected, the returns would be less than those shown.
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	During the ten-year period ended December 31, 2012, the Fund’s highest and lowest quarterly returns were 31.67% and -36.58%, respectively, for the quarters ended September 30, 2009 and December 31, 2008.
Performance Table Heading	rr_PerformanceTableHeading	Average Annual Total Returns for the Periods Ended December 31, 2012
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	All 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	After-tax returns are not relevant to investors who hold Fund shares in tax-deferred accounts such as IRAs or employer-sponsored retirement plans.
Performance Table One Class of after Tax Shown [Text]	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	The table below shows the variability of the Fund’s average annual returns and how they compare over the time periods indicated with those of a broad measure of market performance and an index of funds with similar investment objectives. All 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. After-tax returns are shown for Class A shares only; after-tax returns for other share classes will vary. Your own actual after-tax returns will depend on your specific tax situation and may differ from what is shown here. After-tax returns are not relevant to investors who hold Fund shares in tax-deferred accounts such as IRAs or employer-sponsored retirement plans. Both the bar chart and the table assume that all distributions have been reinvested. Performance reflects fee waivers, if any, in effect during the periods presented. If any such waivers were not in place, returns would be reduced. Prior to July 1, 2004, Class R3 shares were designated Class S shares, which had lower fees and expenses. The performance information in the table prior to July 1, 2004 is based on the performance of the Class S shares. If current fees and expenses had been in effect, performance would have been lower. Performance is not shown for Class R6 shares, which have not been offered for a full calendar year.
Nuveen Real Estate Securities Fund | Class A
Risk/Return:	rr_RiskReturnAbstract
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 lesser of purchase price or redemption proceeds)	rr_MaximumDeferredSalesChargeOverOther	none	[1]
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Exchange Fee	rr_ExchangeFeeOverRedemption	none
Annual Low Balance Account Fee (for accounts under $1,000)	rr_MaximumAccountFee	15	[2]
Management Fees	rr_ManagementFeesOverAssets	0.83%
Distribution and/or Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	0.25%
Other Expenses	rr_OtherExpensesOverAssets	0.20%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.28%
1 Year	rr_ExpenseExampleYear01	698
3 Years	rr_ExpenseExampleYear03	958
5 Years	rr_ExpenseExampleYear05	1,237
10 Years	rr_ExpenseExampleYear10	2,031
1 Year	rr_ExpenseExampleNoRedemptionYear01	698
3 Years	rr_ExpenseExampleNoRedemptionYear03	958
5 Years	rr_ExpenseExampleNoRedemptionYear05	1,237
10 Years	rr_ExpenseExampleNoRedemptionYear10	2,031
2003	rr_AnnualReturn2003	37.23%
2004	rr_AnnualReturn2004	32.06%
2005	rr_AnnualReturn2005	15.03%
2006	rr_AnnualReturn2006	39.13%
2007	rr_AnnualReturn2007	(15.42%)
2008	rr_AnnualReturn2008	(34.96%)
2009	rr_AnnualReturn2009	30.18%
2010	rr_AnnualReturn2010	30.24%
2011	rr_AnnualReturn2011	7.69%
2012	rr_AnnualReturn2012	18.07%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	highest
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2009
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	31.67%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	lowest
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Dec. 31, 2008
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	(36.58%)
1 Year	rr_AverageAnnualReturnYear01	11.31%
5 Years	rr_AverageAnnualReturnYear05	5.74%
10 Years	rr_AverageAnnualReturnYear10	12.48%
Nuveen Real Estate Securities Fund | Class B
Risk/Return:	rr_RiskReturnAbstract
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 lesser of purchase price or redemption proceeds)	rr_MaximumDeferredSalesChargeOverOther	5.00%	[1]
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Exchange Fee	rr_ExchangeFeeOverRedemption	none
Annual Low Balance Account Fee (for accounts under $1,000)	rr_MaximumAccountFee	15	[2]
Management Fees	rr_ManagementFeesOverAssets	0.83%
Distribution and/or Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other Expenses	rr_OtherExpensesOverAssets	0.20%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	2.03%
1 Year	rr_ExpenseExampleYear01	706
3 Years	rr_ExpenseExampleYear03	937
5 Years	rr_ExpenseExampleYear05	1,193
10 Years	rr_ExpenseExampleYear10	2,166
1 Year	rr_ExpenseExampleNoRedemptionYear01	206
3 Years	rr_ExpenseExampleNoRedemptionYear03	637
5 Years	rr_ExpenseExampleNoRedemptionYear05	1,093
10 Years	rr_ExpenseExampleNoRedemptionYear10	2,166
1 Year	rr_AverageAnnualReturnYear01	12.18%
5 Years	rr_AverageAnnualReturnYear05	6.03%
10 Years	rr_AverageAnnualReturnYear10	12.31%
Nuveen Real Estate Securities Fund | Class C
Risk/Return:	rr_RiskReturnAbstract
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 lesser of purchase price or redemption proceeds)	rr_MaximumDeferredSalesChargeOverOther	1.00%	[1]
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Exchange Fee	rr_ExchangeFeeOverRedemption	none
Annual Low Balance Account Fee (for accounts under $1,000)	rr_MaximumAccountFee	15	[2]
Management Fees	rr_ManagementFeesOverAssets	0.83%
Distribution and/or Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other Expenses	rr_OtherExpensesOverAssets	0.20%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	2.03%
1 Year	rr_ExpenseExampleYear01	206
3 Years	rr_ExpenseExampleYear03	637
5 Years	rr_ExpenseExampleYear05	1,093
10 Years	rr_ExpenseExampleYear10	2,358
1 Year	rr_ExpenseExampleNoRedemptionYear01	206
3 Years	rr_ExpenseExampleNoRedemptionYear03	637
5 Years	rr_ExpenseExampleNoRedemptionYear05	1,093
10 Years	rr_ExpenseExampleNoRedemptionYear10	2,358
1 Year	rr_AverageAnnualReturnYear01	17.19%
5 Years	rr_AverageAnnualReturnYear05	6.21%
10 Years	rr_AverageAnnualReturnYear10	12.32%
Nuveen Real Estate Securities Fund | Class R3
Risk/Return:	rr_RiskReturnAbstract
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 lesser of purchase price or redemption proceeds)	rr_MaximumDeferredSalesChargeOverOther	none	[1]
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Exchange Fee	rr_ExchangeFeeOverRedemption	none
Annual Low Balance Account Fee (for accounts under $1,000)	rr_MaximumAccountFee	none	[2]
Management Fees	rr_ManagementFeesOverAssets	0.83%
Distribution and/or Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	0.50%
Other Expenses	rr_OtherExpensesOverAssets	0.20%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.53%
1 Year	rr_ExpenseExampleYear01	156
3 Years	rr_ExpenseExampleYear03	483
5 Years	rr_ExpenseExampleYear05	834
10 Years	rr_ExpenseExampleYear10	1,824
1 Year	rr_ExpenseExampleNoRedemptionYear01	156
3 Years	rr_ExpenseExampleNoRedemptionYear03	483
5 Years	rr_ExpenseExampleNoRedemptionYear05	834
10 Years	rr_ExpenseExampleNoRedemptionYear10	1,824
1 Year	rr_AverageAnnualReturnYear01	17.80%
5 Years	rr_AverageAnnualReturnYear05	6.74%
10 Years	rr_AverageAnnualReturnYear10	12.92%
Nuveen Real Estate Securities Fund | Class R6
Risk/Return:	rr_RiskReturnAbstract
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 lesser of purchase price or redemption proceeds)	rr_MaximumDeferredSalesChargeOverOther	none	[1]
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Exchange Fee	rr_ExchangeFeeOverRedemption	none
Annual Low Balance Account Fee (for accounts under $1,000)	rr_MaximumAccountFee	none	[2]
Management Fees	rr_ManagementFeesOverAssets	0.83%	[3]
Distribution and/or Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none	[3]
Other Expenses	rr_OtherExpensesOverAssets	0.07%	[3]
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	0.90%	[3]
1 Year	rr_ExpenseExampleYear01	92
3 Years	rr_ExpenseExampleYear03	287
5 Years	rr_ExpenseExampleYear05	498
10 Years	rr_ExpenseExampleYear10	1,108
1 Year	rr_ExpenseExampleNoRedemptionYear01	92
3 Years	rr_ExpenseExampleNoRedemptionYear03	287
5 Years	rr_ExpenseExampleNoRedemptionYear05	498
10 Years	rr_ExpenseExampleNoRedemptionYear10	1,108
Nuveen Real Estate Securities Fund | Class I
Risk/Return:	rr_RiskReturnAbstract
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 lesser of purchase price or redemption proceeds)	rr_MaximumDeferredSalesChargeOverOther	none	[1]
Maximum Sales Charge (Load) Imposed on Reinvested Dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Exchange Fee	rr_ExchangeFeeOverRedemption	none
Annual Low Balance Account Fee (for accounts under $1,000)	rr_MaximumAccountFee	15	[2]
Management Fees	rr_ManagementFeesOverAssets	0.83%
Distribution and/or Service (12b-1) Fees	rr_DistributionAndService12b1FeesOverAssets	none
Other Expenses	rr_OtherExpensesOverAssets	0.20%
Total Annual Fund Operating Expenses	rr_ExpensesOverAssets	1.03%
1 Year	rr_ExpenseExampleYear01	105
3 Years	rr_ExpenseExampleYear03	328
5 Years	rr_ExpenseExampleYear05	569
10 Years	rr_ExpenseExampleYear10	1,259
1 Year	rr_ExpenseExampleNoRedemptionYear01	105
3 Years	rr_ExpenseExampleNoRedemptionYear03	328
5 Years	rr_ExpenseExampleNoRedemptionYear05	569
10 Years	rr_ExpenseExampleNoRedemptionYear10	1,259
1 Year	rr_AverageAnnualReturnYear01	18.34%
5 Years	rr_AverageAnnualReturnYear05	7.26%
10 Years	rr_AverageAnnualReturnYear10	13.44%
Nuveen Real Estate Securities Fund | (return after taxes on distributions) | Class A
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	9.57%
5 Years	rr_AverageAnnualReturnYear05	4.72%
10 Years	rr_AverageAnnualReturnYear10	10.31%
Nuveen Real Estate Securities Fund | (return after taxes on distributions and sale of Fund shares) | Class A
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	7.58%
5 Years	rr_AverageAnnualReturnYear05	4.34%
10 Years	rr_AverageAnnualReturnYear10	9.91%
Nuveen Real Estate Securities Fund | Morgan Stanley REIT Index (reflects no deduction for fees, expenses or taxes)
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	17.77%
5 Years	rr_AverageAnnualReturnYear05	5.58%
10 Years	rr_AverageAnnualReturnYear10	11.58%
Nuveen Real Estate Securities Fund | Lipper Real Estate Classification Average (reflects no deduction for taxes or certain expenses)
Risk/Return:	rr_RiskReturnAbstract
1 Year	rr_AverageAnnualReturnYear01	17.73%
5 Years	rr_AverageAnnualReturnYear05	4.95%
10 Years	rr_AverageAnnualReturnYear10	10.78%

[1] The contingent deferred sales charge ("CDSC") on Class B shares declines over a six-year period from purchase. The CDSC on Class C shares applies only to redemptions within 12 months of purchase.

[2] Fee applies to the following types of accounts under $1,000 held directly with the Fund: individual retirement accounts (IRAs), Coverdell Education Savings Accounts and accounts established pursuant to the Uniform Transfers to Minors Act (UTMA) or Uniform Gifts to Minors Act (UGMA).

[3] Class R6 shares were established on April 30, 2013. Accordingly, expenses are based upon the actual expenses incurred by the other share classes; adjusted to reflect anticipated savings resulting from the fact that sub-transfer agent and similar fees are not charged to Class R6 shares.