XML 152 R267.htm IDEA: XBRL DOCUMENT v3.24.1.u1
Label Element Value
Nuveen Short Term Bond Index Fund  
Risk/Return: rr_RiskReturnAbstract  
Risk/Return [Heading] rr_RiskReturnHeading Nuveen Short Term Bond Index Fund
Objective [Heading] rr_ObjectiveHeading Investment objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock

The Fund seeks total return that corresponds with the total return of a short-term U.S. investment-grade bond market index.

Expense [Heading] rr_ExpenseHeading Fees and expenses
Expense Narrative [Text Block] rr_ExpenseNarrativeTextBlock

The following tables describe the fees and expenses that you may pay if you buy, hold and sell 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 “How You Can Buy and Sell Shares” on page 192 of the Fund’s Prospectus and “Purchase and Redemption of Fund Shares” on page 104 of the Fund’s Statement of Additional Information. In addition, more information about sales charge discounts and waivers for purchases of shares through specific financial intermediaries is set forth in the appendix to the Fund’s Prospectus entitled “Variations in Sales Charge Reductions and Waivers Available Through Certain Intermediaries.”

The tables and examples below do not reflect any commissions that shareholders may be required to pay directly to their financial intermediaries when buying or selling Class I shares.
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 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 fiscal year ended March 31, 2023, the Fund’s portfolio turnover rate was 69% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 69.00%
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 shares of 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 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, before fee waivers and/or expense reimbursements, remain the same. The example assumes that the Fund’s fee waiver and/or expense reimbursement arrangements will each remain in place for the durations noted in the table above. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading] rr_StrategyHeading Principal investment strategies
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock

Under normal circumstances, the Fund invests at least 80% of its assets in bonds within its benchmark and portfolio tracking index, the Bloomberg U.S. 1–3 Year Government/Credit Bond Index (the “Index”). The Fund uses a sampling technique to create a portfolio that closely matches the overall investment characteristics of the Index (for example, duration, sector diversification and credit quality) without investing in all of the securities in the Index. At times the Fund may purchase securities not held in the Index, but which Teachers Advisors, LLC (“Advisors”) believes have similar investment characteristics to securities held in its index. Generally, the Fund intends to invest in a wide spectrum of public, investment-grade, taxable debt securities denominated in U.S. dollars including United States treasury debt, government-related debt, and corporate issues. The Fund has a policy of maintaining a dollar weighted average maturity of no more than three years. For purposes of the 80% investment policy, the term “assets” means net assets, plus the amount of any borrowings for investment purposes.

The securities purchased by the Fund will mainly be high-quality instruments rated in the top four credit categories by a nationally recognized statistical rating organization (“NRSRO”) or deemed to be of the same quality by Advisors using its own credit quality analysis. The Fund may continue to hold instruments that were rated as high-quality when purchased, but which subsequently are downgraded to below-investment-grade status or have their ratings withdrawn by one or more rating agencies.

Because the return of the Index is not reduced by investment and other operating expenses, the Fund’s ability to match the Index is negatively affected by the costs of buying and selling securities, as well as other fees and expenses. The use of this index by the Fund is not a fundamental policy of the Fund and may be changed without shareholder approval.

The Fund may also invest in foreign securities, including emerging markets fixed-income securities and non-dollar-denominated instruments. Under most circumstances, the Fund’s investments in fixed-income securities of foreign issuers constitute less than 20% of the Fund’s assets.

The Fund is classified as a diversified investment company, as defined under the Investment Company Act of 1940, as amended (the “1940 Act”). However, the Fund may become non-diversified under the 1940 Act without the approval of Fund shareholders solely as a result of a change in relative market capitalization

or index weighting of one or more constituents of its benchmark index, the Bloomberg U.S. 1–3 Year Government/Credit Bond Index, which the Fund seeks to track.

Risk [Heading] rr_RiskHeading Principal investment risks
Bar Chart and Performance Table [Heading] rr_BarChartAndPerformanceTableHeading Past performance
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock

The following chart and table help illustrate some of the risks of investing in the Fund by showing changes in the Fund’s performance from year to year. The bar chart shows the annual total returns of Class R6 of the Fund, before taxes, in each full calendar year since inception of the Class R6. Because the expenses vary across share classes, the performance of Class R6 may vary from the other share classes. Below the bar chart are the best and worst returns of Class R6 for a calendar quarter during the full calendar-year periods covered by the bar chart. The performance table following the bar chart shows the Fund’s average annual total returns for Class R6, Class I, Premier, Retirement, Class A and Class W classes over the applicable one-year, five-year, ten-year and since-inception periods ended December 31, 2022, and how those returns compare to those of the Fund’s benchmark index. After-tax performance is shown only for Class R6 shares, and after-tax returns for the other classes of shares will vary from the after-tax returns presented for Class R6 shares.

The returns shown below reflect previous agreements by Advisors to waive or reimburse the Fund for certain fees and expenses. Without these waivers and reimbursements, the returns of the Fund would have been lower. Past performance of the Fund (before and after taxes) is not necessarily an indication of how it will perform in the future. The benchmark index listed below is unmanaged, and you cannot invest directly in an index. The returns for the benchmark index reflect no deduction for fees, expenses or taxes.

For current performance information of each share class, including performance to the most recent month-end, please visit www.nuveen.com/performance or by calling 800-257-8787.
Performance Information Illustrates Variability of Returns [Text] rr_PerformanceInformationIllustratesVariabilityOfReturns The following chart and table help illustrate some of the risks of investing in the Fund by showing changes in the Fund’s performance from year to year.
Performance Availability Website Address [Text] rr_PerformanceAvailabilityWebSiteAddress www.nuveen.com/performance
Performance Past Does Not Indicate Future [Text] rr_PerformancePastDoesNotIndicateFuture Past performance of the Fund (before and after taxes) is not necessarily an indication of how it will perform in the future.
Bar Chart [Heading] rr_BarChartHeading ANNUAL TOTAL RETURNS FOR CLASS R6 SHARES (%)† Nuveen Short Term Bond Index Fund
Bar Chart Footnotes [Text Block] rr_BarChartFootnotesTextBlock

† The year-to-date return as of the most recent calendar quarter, which ended on June 30, 2023, was 1.20%.
Bar Chart Closing [Text Block] rr_BarChartClosingTextBlock

Best quarter: 1.71%, for the quarter ended March 31, 2020. Worst quarter: -2.47%, for the quarter ended March 31, 2022.
Performance Table Heading rr_PerformanceTableHeading AVERAGE ANNUAL TOTAL RETURNS For the Periods Ended December 31, 2022
Index No Deduction for Fees, Expenses, Taxes [Text] rr_IndexNoDeductionForFeesExpensesTaxes The returns for the benchmark index reflect no deduction for fees, expenses or taxes.
Performance Table Uses Highest Federal Rate rr_PerformanceTableUsesHighestFederalRate After-tax returns are calculated using the historical highest individual federal marginal income tax rates in effect during the periods shown and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred rr_PerformanceTableNotRelevantToTaxDeferred The after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(a), 401(k) or 403(b) plans or Individual Retirement Accounts (IRAs).
Performance Table One Class of after Tax Shown [Text] rr_PerformanceTableOneClassOfAfterTaxShown After-tax returns are shown for only one class, and after-tax returns for other classes will vary.
Performance Table Closing [Text Block] rr_PerformanceTableClosingTextBlock Current performance of the Fund’s shares may be higher or lower than that shown above.

After-tax returns are calculated using the historical highest individual federal marginal income tax rates in effect during the periods shown and do not reflect the impact of state and local taxes. Actual after-tax returns depend on the investor’s tax situation and may differ from those shown. The after-tax returns shown are not relevant to investors who hold their Fund shares through tax-deferred arrangements such as 401(a), 401(k) or 403(b) plans or Individual Retirement Accounts (IRAs). After-tax returns are shown for only one class, and after-tax returns for other classes will vary.
Thirty Day Yield Phone rr_ThirtyDayYieldPhone 800-257-8787
Nuveen Short Term Bond Index Fund | Risk Lose Money [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock You could lose money over short or long periods by investing in this Fund.
Nuveen Short Term Bond Index Fund | Income Volatility Risk  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock

· Income Volatility Risk—The risk that the level of current income from a portfolio of fixed-income investments may decline in certain interest rate environments.
Nuveen Short Term Bond Index Fund | Credit Risk (a type of Issuer Risk)  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock

· Credit Risk (a type of Issuer Risk)—The risk that the issuer of fixed-income investments may not be able or willing, or may be perceived (whether by market participants, rating agencies, pricing services or otherwise) as not able or willing, to meet interest or principal payments when the payments become due.
Nuveen Short Term Bond Index Fund | Credit Spread Risk  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock

· Credit Spread Risk—The risk that credit spreads (i.e., the difference in yield between securities that is due to differences in each security’s respective credit quality) may increase when market participants believe that bonds generally have a greater risk of default, which could result in a decline in the market values of the Fund’s debt securities.
Nuveen Short Term Bond Index Fund | Call Risk  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock

· Call Risk—The risk that, during periods of falling interest rates, an issuer may call (or repay) a fixed-income security prior to maturity, resulting in a decline in the Fund’s income.

Nuveen Short Term Bond Index Fund | Market Volatility, Liquidity and Valuation Risk (types of Market Risk)  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock

· Market Volatility, Liquidity and Valuation Risk (types of Market Risk)—The risk that volatile or dramatic reductions in trading activity make it difficult for the Fund to properly value its investments and that the Fund may not be able to purchase or sell an investment at an attractive price, if at all.
Nuveen Short Term Bond Index Fund | Interest Rate Risk (a type of Market Risk)  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock

· Interest Rate Risk (a type of Market Risk)—The risk that increases in interest rates can cause the prices of fixed-income investments to decline. This risk is heightened to the extent the Fund invests in longer duration fixed-income investments and during periods when prevailing interest rates are low or negative. Low interest rates may increase the Fund’s exposure to risks associated with rising interest rates, and the Fund may also be subject to heightened levels of interest rate risk due to rising interest rates (including a sharp rise in interest rates). In general, changing interest rates could have unpredictable effects on the markets and may expose fixed-income and related markets to heightened volatility.

Nuveen Short Term Bond Index Fund | Issuer Risk (often called Financial Risk)  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock

· Issuer Risk (often called Financial Risk)—The risk that an issuer’s earnings prospects and overall financial position will deteriorate, causing a decline in the value of the issuer’s financial instruments over short or extended periods of time.

Nuveen Short Term Bond Index Fund | U.S. Government Securities Risk  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock

· U.S. Government Securities Risk—Securities issued by the U.S. Government or one of its agencies or instrumentalities may receive varying levels of support from the U.S. Government, which could affect the Fund’s ability to recover should they default. To the extent the Fund invests significantly in securities issued or guaranteed by the U.S. Government or its agencies or instrumentalities, any market movements, regulatory changes or changes in political or economic conditions that affect the securities of the U.S. Government or its agencies or instrumentalities in which the Fund invests may have a significant impact on the Fund’s performance.
Nuveen Short Term Bond Index Fund | Illiquid Investments Risk  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock

· Illiquid Investments Risk—The risk that illiquid investments may be difficult to sell for the value at which they are carried, if at all, or at any price within the desired time frame.

Nuveen Short Term Bond Index Fund | Downgrade Risk  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock

· Downgrade Risk—The risk that securities are subsequently downgraded should Advisors and/or rating agencies believe the issuer’s business outlook or creditworthiness has deteriorated.
Nuveen Short Term Bond Index Fund | Index Risk  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock

· Index Risk—The risk that the Fund’s performance may not correspond to its benchmark index for any period of time and may underperform such index or the overall financial market. Additionally, to the extent that the Fund’s investments vary from the composition of its benchmark index, the Fund’s performance could potentially vary from the index’s performance to a greater extent than if the Fund merely attempted to replicate the index.
Nuveen Short Term Bond Index Fund | Fixed-Income Foreign Investment Risk  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock

· Fixed-Income Foreign Investment Risk—Investment in fixed-income securities or financial instruments of foreign issuers involves increased risks due to adverse issuer, political, regulatory, currency, market or economic developments as well as armed conflicts. These developments may impact the ability of a foreign debt issuer to make timely and ultimate payments on its debt obligations to the Fund or impair the Fund’s ability to enforce its rights against the foreign debt issuer. These risks are heightened in emerging or developing markets. Foreign investments may also have lower overall liquidity and be more difficult to value than investments in U.S. issuers. Foreign investments may also be subject to risk of loss because of more or less foreign government regulation, less public information, less stringent investor protections, and less stringent accounting, corporate governance, financial reporting and disclosure standards. The imposition of sanctions, exchange controls (including repatriation restrictions), confiscations, trade restrictions (including tariffs) and other restrictions by the United States or other governments may also negatively impact the Fund’s investments. Economic sanctions and other similar governmental actions or developments could, among other things, effectively restrict or eliminate the Fund’s ability to purchase or sell certain foreign securities or groups of foreign securities, and/or thus may make the Fund’s investments in such securities less liquid (or illiquid) or more difficult to value. The type and severity of sanctions and other measures that may be imposed could vary broadly in scope, and their impact is impossible to predict.
Nuveen Short Term Bond Index Fund | Risk Nondiversified Status [Member]  
Risk/Return: rr_RiskReturnAbstract  
Risk [Text Block] rr_RiskTextBlock

· Non-Diversification Risk—While the Fund is considered to be a diversified investment company under the 1940 Act, the Fund may become non-diversified under the 1940 Act without Fund shareholder approval when necessary to continue to track its benchmark index. Non-diversified status means that the Fund can invest a greater percentage of its assets in the securities of a single issuer than a diversified fund. Investing in a non-diversified fund involves greater risk than investing in a diversified fund because a loss in value of a particular investment may have a greater effect on the fund’s return since that investment may represent a larger portion of the fund’s total portfolio assets.

Nuveen Short Term Bond Index Fund | Bloomberg U.S. 1-3 Year Government/Credit Bond Index  
Risk/Return: rr_RiskReturnAbstract  
Index No Deduction for Fees, Expenses, Taxes [Text] rr_IndexNoDeductionForFeesExpensesTaxes (reflects no deductions for fees, expenses or taxes)
Label rr_AverageAnnualReturnLabel Bloomberg U.S. 1-3 Year Government/Credit Bond Index
1 Year rr_AverageAnnualReturnYear01 (3.69%)
5 Years rr_AverageAnnualReturnYear05 0.92%
Since Inception rr_AverageAnnualReturnSinceInception 0.91% [1]
Nuveen Short Term Bond Index 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) rr_MaximumDeferredSalesChargeOverOfferingPrice none
Maximum sales charge (load) imposed on reinvested dividends and other distributions rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther none
Redemption or exchange fee rr_RedemptionFeeOverRedemption none
Annual low balance account fee (for accounts under $1,000) rr_ShareholderFeeOther none
Management fees rr_ManagementFeesOverAssets 0.05%
Distribution (Rule 12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.03%
Total annual Fund operating expenses rr_ExpensesOverAssets 0.08%
Waivers and expense reimbursements rr_FeeWaiverOrReimbursementOverAssets none [2]
Total annual Fund operating expenses after fee waiver and/or expense reimbursement rr_NetExpensesOverAssets 0.08%
Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination July 31, 2024
1 Year rr_ExpenseExampleYear01 $ 8
3 Years rr_ExpenseExampleYear03 26
5 Years rr_ExpenseExampleYear05 45
10 Years rr_ExpenseExampleYear10 $ 103
Annual Return 2016 rr_AnnualReturn2016 0.98%
Annual Return 2017 rr_AnnualReturn2017 0.69%
Annual Return 2018 rr_AnnualReturn2018 1.49%
Annual Return 2019 rr_AnnualReturn2019 3.89%
Annual Return 2020 rr_AnnualReturn2020 3.28%
Annual Return 2021 rr_AnnualReturn2021 (0.57%)
Annual Return 2022 rr_AnnualReturn2022 (3.78%)
Year to Date Return, Label rr_YearToDateReturnLabel The year-to-date return as of the most recent calendar quarter, which ended on June 30, 2023, was
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2023
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn 1.20%
Label rr_HighestQuarterlyReturnLabel Best quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Mar. 31, 2020
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 1.71%
Label rr_LowestQuarterlyReturnLabel Worst quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Mar. 31, 2022
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (2.47%)
1 Year rr_AverageAnnualReturnYear01 (3.78%)
5 Years rr_AverageAnnualReturnYear05 0.82%
Since Inception rr_AverageAnnualReturnSinceInception 0.77%
Inception Date rr_AverageAnnualReturnInceptionDate Aug. 07, 2015
Nuveen Short Term Bond Index Fund | Class R6 | After Taxes on Distributions  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 (4.24%)
5 Years rr_AverageAnnualReturnYear05 0.16%
Since Inception rr_AverageAnnualReturnSinceInception 0.17%
Nuveen Short Term Bond Index Fund | Class R6 | After Taxes on Distributions and Sales  
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 (2.24%)
5 Years rr_AverageAnnualReturnYear05 0.37%
Since Inception rr_AverageAnnualReturnSinceInception 0.34%
Nuveen Short Term Bond Index 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) rr_MaximumDeferredSalesChargeOverOfferingPrice none
Maximum sales charge (load) imposed on reinvested dividends and other distributions rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther none
Redemption or exchange fee rr_RedemptionFeeOverRedemption none
Annual low balance account fee (for accounts under $1,000) rr_ShareholderFeeOther none
Management fees rr_ManagementFeesOverAssets 0.05%
Distribution (Rule 12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.15%
Total annual Fund operating expenses rr_ExpensesOverAssets 0.20%
Waivers and expense reimbursements rr_FeeWaiverOrReimbursementOverAssets none [2]
Total annual Fund operating expenses after fee waiver and/or expense reimbursement rr_NetExpensesOverAssets 0.20%
Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination July 31, 2024
1 Year rr_ExpenseExampleYear01 $ 20
3 Years rr_ExpenseExampleYear03 64
5 Years rr_ExpenseExampleYear05 113
10 Years rr_ExpenseExampleYear10 $ 255
1 Year rr_AverageAnnualReturnYear01 (3.90%)
5 Years rr_AverageAnnualReturnYear05 0.67%
Since Inception rr_AverageAnnualReturnSinceInception 0.65% [3]
Inception Date rr_AverageAnnualReturnInceptionDate Dec. 04, 2015
Nuveen Short Term Bond Index Fund | Premier Class  
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) rr_MaximumDeferredSalesChargeOverOfferingPrice none
Maximum sales charge (load) imposed on reinvested dividends and other distributions rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther none
Redemption or exchange fee rr_RedemptionFeeOverRedemption none
Annual low balance account fee (for accounts under $1,000) rr_ShareholderFeeOther none
Management fees rr_ManagementFeesOverAssets 0.05%
Distribution (Rule 12b-1) fees rr_DistributionAndService12b1FeesOverAssets 0.15%
Other expenses rr_OtherExpensesOverAssets 0.04%
Total annual Fund operating expenses rr_ExpensesOverAssets 0.24%
Waivers and expense reimbursements rr_FeeWaiverOrReimbursementOverAssets none [2]
Total annual Fund operating expenses after fee waiver and/or expense reimbursement rr_NetExpensesOverAssets 0.24%
Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination July 31, 2024
1 Year rr_ExpenseExampleYear01 $ 25
3 Years rr_ExpenseExampleYear03 77
5 Years rr_ExpenseExampleYear05 135
10 Years rr_ExpenseExampleYear10 $ 306
1 Year rr_AverageAnnualReturnYear01 (3.94%)
5 Years rr_AverageAnnualReturnYear05 0.65%
Since Inception rr_AverageAnnualReturnSinceInception 0.60%
Inception Date rr_AverageAnnualReturnInceptionDate Aug. 07, 2015
Nuveen Short Term Bond Index Fund | Retirement Class  
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) rr_MaximumDeferredSalesChargeOverOfferingPrice none
Maximum sales charge (load) imposed on reinvested dividends and other distributions rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther none
Redemption or exchange fee rr_RedemptionFeeOverRedemption none
Annual low balance account fee (for accounts under $1,000) rr_ShareholderFeeOther none
Management fees rr_ManagementFeesOverAssets 0.05%
Distribution (Rule 12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.28%
Total annual Fund operating expenses rr_ExpensesOverAssets 0.33%
Waivers and expense reimbursements rr_FeeWaiverOrReimbursementOverAssets none [2]
Total annual Fund operating expenses after fee waiver and/or expense reimbursement rr_NetExpensesOverAssets 0.33%
Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination July 31, 2024
1 Year rr_ExpenseExampleYear01 $ 34
3 Years rr_ExpenseExampleYear03 106
5 Years rr_ExpenseExampleYear05 185
10 Years rr_ExpenseExampleYear10 $ 418
1 Year rr_AverageAnnualReturnYear01 (4.02%)
5 Years rr_AverageAnnualReturnYear05 0.57%
Since Inception rr_AverageAnnualReturnSinceInception 0.52%
Inception Date rr_AverageAnnualReturnInceptionDate Aug. 07, 2015
Nuveen Short Term Bond Index Fund | Class A  
Risk/Return: rr_RiskReturnAbstract  
Maximum sales charge (load) imposed on purchases (as a percentage of offering price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice 2.50%
Maximum deferred sales charge (load) rr_MaximumDeferredSalesChargeOverOfferingPrice none
Maximum sales charge (load) imposed on reinvested dividends and other distributions rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther none
Redemption or exchange fee rr_RedemptionFeeOverRedemption none
Annual low balance account fee (for accounts under $1,000) rr_ShareholderFeeOther $ 15.00
Management fees rr_ManagementFeesOverAssets 0.05%
Distribution (Rule 12b-1) fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other expenses rr_OtherExpensesOverAssets 0.07%
Total annual Fund operating expenses rr_ExpensesOverAssets 0.37%
Waivers and expense reimbursements rr_FeeWaiverOrReimbursementOverAssets none [2]
Total annual Fund operating expenses after fee waiver and/or expense reimbursement rr_NetExpensesOverAssets 0.37%
Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination July 31, 2024
1 Year rr_ExpenseExampleYear01 $ 287
3 Years rr_ExpenseExampleYear03 366
5 Years rr_ExpenseExampleYear05 452
10 Years rr_ExpenseExampleYear10 $ 706
1 Year rr_AverageAnnualReturnYear01 (6.57%)
5 Years rr_AverageAnnualReturnYear05 (0.03%)
Since Inception rr_AverageAnnualReturnSinceInception 0.08%
Inception Date rr_AverageAnnualReturnInceptionDate Aug. 07, 2015 [4]
Nuveen Short Term Bond Index Fund | Class W  
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) rr_MaximumDeferredSalesChargeOverOfferingPrice none
Maximum sales charge (load) imposed on reinvested dividends and other distributions rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther none
Redemption or exchange fee rr_RedemptionFeeOverRedemption none
Annual low balance account fee (for accounts under $1,000) rr_ShareholderFeeOther none
Management fees rr_ManagementFeesOverAssets 0.05%
Distribution (Rule 12b-1) fees rr_DistributionAndService12b1FeesOverAssets none
Other expenses rr_OtherExpensesOverAssets 0.03%
Total annual Fund operating expenses rr_ExpensesOverAssets 0.08%
Waivers and expense reimbursements rr_FeeWaiverOrReimbursementOverAssets (0.08%) [2],[5]
Total annual Fund operating expenses after fee waiver and/or expense reimbursement rr_NetExpensesOverAssets none
Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination July 31, 2024
1 Year rr_ExpenseExampleYear01 none
3 Years rr_ExpenseExampleYear03 none
5 Years rr_ExpenseExampleYear05 none
10 Years rr_ExpenseExampleYear10 none
1 Year rr_AverageAnnualReturnYear01 (3.70%)
5 Years rr_AverageAnnualReturnYear05 0.91% [3]
Since Inception rr_AverageAnnualReturnSinceInception 0.83% [3]
Inception Date rr_AverageAnnualReturnInceptionDate Sep. 28, 2018
[1]

Performance is calculated from the inception date of the Class R6.
[2]

Under the Fund’s expense reimbursement arrangements, the Fund’s investment adviser, Teachers Advisors, LLC, has contractually agreed to reimburse the Fund for any Total annual Fund operating expenses (excluding interest, taxes, brokerage commissions or other transactional expenses, Acquired fund fees and expenses and extraordinary expenses) that exceed: (i) 0.10% of average daily net assets for Class R6 shares; (ii) 0.25% of average daily net assets for Class I shares; (iii) 0.25% of average daily net assets for Premier Class shares; (iv) 0.35% of average daily net assets for Retirement Class shares; (v) 0.45% of average daily net assets for Class A shares; and (vi) 0.10% of average daily net assets for Class W shares of the Fund. These expense reimbursement arrangements will continue through at least July 31, 2024, unless changed with approval of the Board of Trustees.
[3]

The performance shown for the Class I and Class W that is prior to their respective inception dates is based on performance of the Class R6. The performance for these periods has not been restated to reflect the actual expenses of the Class I and Class W. If these actual expenses had been reflected, the performance of these two classes shown for these periods would have been different because the Class I and Class W have different expenses than the Class R6.
[4]

The Class A average annual total returns have been restated to reflect a maximum up-front sales charge of 2.50% applicable to the purchase of Class A shares, which was effective as of May 6, 2024.
[5]

Teachers Advisors, LLC has contractually agreed to waive and/or reimburse Class W’s Management fees and Other expenses (excluding interest, taxes, brokerage commissions or other transactional expenses, Acquired fund fees and expenses, Trustee expenses and extraordinary expenses) in their entirety. Teachers Advisors, LLC expects these waiver and/or reimbursement arrangements to remain in effect indefinitely, unless changed or terminated with approval of the Board of Trustees.