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Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Risk/Return [Heading] rr_RiskReturnHeading TIAA-CREF Large-Cap Growth Index Fund
Objective [Heading] rr_ObjectiveHeading Investment objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock

The Fund seeks a favorable long-term total return, mainly through capital appreciation, by investing primarily in a portfolio of equity securities of large domestic growth companies based on a market index.

Expense [Heading] rr_ExpenseHeading Fees and expenses
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:

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)
Fee Waiver or Reimbursement over Assets, Date of Termination rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination 2016-02-29
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 fiscal year ended October 31, 2014, the Fund’s portfolio turnover rate was 21% of the average value of its portfolio.

Portfolio Turnover, Rate rr_PortfolioTurnoverRate 21.00%rr_PortfolioTurnoverRate
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 expense reimbursements, remain the same. The example assumes that the Fund’s expense reimbursement agreement will remain in place through February 29, 2016, but that there will be no waiver or expense reimbursement agreement in effect thereafter. 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 securities of its benchmark index (the Russell 1000® Growth Index). For purposes of the 80% investment policy, “large-cap” securities are securities of issuers with a capitalization equal to or greater than the top 80% of issuers by capitalization within the Russell 1000® Index at the time of purchase. The Russell 1000®Growth Index is a subset of the Russell 1000® Index, which represents the performance of the large-cap growth segment of the U.S. equity universe. It includes those Russell 1000® Index companies with higher price-to-book ratios and higher forecasted growth values. The Fund buys most, but not necessarily all, of the stocks in its benchmark index, and will attempt to closely match the overall investment characteristics of its benchmark index. For purposes of the 80% investment policy, the term “assets” means net assets, plus the amount of any borrowings for investment purposes.


The Fund is designed to track various U.S. equity markets as a whole or a segment of these markets. The Fund primarily invests its assets in equity securities its investment adviser, Teachers Advisors, Inc. (“Advisors”), has selected to track a designated stock market index. Because the return of an index is not reduced by investment and other operating expenses, the Fund’s ability to match the returns of the Russell 1000® Growth Index is negatively affected by the costs of buying and selling securities as well as the Fund’s fees and other expenses. The use of a particular index by the Fund is not a fundamental policy and may be changed without shareholder approval. The portfolio management team of Advisors will attempt to build a portfolio that generally matches the market weighted investment characteristics of the Fund’s benchmark index.

Risk [Heading] rr_RiskHeading Principal investment risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock

You could lose money over short or long periods by investing in this Fund. An investment in the Fund, due to the nature of the Fund’s portfolio holdings, typically is subject to the following principal investment risks:


· Market Risk—The risk that market prices of portfolio investments held by the Fund may fall rapidly or unpredictably due to a variety of factors, including changing economic, political or market conditions. Market risk may affect a single issuer, industry or sector of the economy, or it may affect the market as a whole.


· Index Risk—The risk that the Fund’s performance will not correspond to its benchmark index for any period of time and may underperform such index or the overall stock 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.


· Issuer Risk (often calledFinancial 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.


· Style Risk—The risk that use of a particular investing style (such as growth or value investing) may fall out of favor in the marketplace for various periods of time and result in underperformance relative to the broader market sector or significant declines in the value of the Fund’s portfolio investments.


· Risks of Growth Investing—Due to their relatively high valuations, growth stocks are typically more volatile than value stocks and may experience a larger decline on a forecast of lower earnings, or a negative event or market development, than would a value stock.


· Large-Cap Risk—The risk that large-capitalization companies are more mature and may grow more slowly than the economy as a whole and tend to go in and out of favor based on market and economic conditions.

Risk Closing [Text Block] rr_RiskClosingTextBlock

Please see the non-summary portion of the Prospectus for more detailed information about the risks described above.

Risk Lose Money [Text] rr_RiskLoseMoney You could lose money over short or long periods by investing in this Fund.
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 the Institutional Class of the Fund, before taxes, in each full calendar year for the last ten years. Because the expenses vary across share classes, the performance of the Institutional Class will vary from the other share classes. Below the bar chart are the best and worst returns of the Institutional Class for a calendar quarter during the period covered by the bar chart. The performance table following the bar chart shows the Fund’s average annual total returns for the Institutional Class and Retirement Class over the one-year, five-year, ten-year and since-inception periods (where applicable) ended December 31, 2014, and how those returns compare to those of the Fund’s benchmark index. After-tax performance is shown only for Institutional Class shares and after-tax returns for the Retirement Class shares will vary from the after-tax returns presented for the Institutional Class 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 the benchmark 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.tiaa-cref.org.

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.tiaa-cref.org
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 THE INSTITUTIONAL CLASS SHARES (%)
Bar Chart Closing [Text Block] rr_BarChartClosingTextBlock

Best quarter: 16.41%, for the quarter ended June 30, 2009. Worst quarter: -22.74%, for the quarter ended December 31, 2008.

Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Best quarter:
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Jun. 30, 2009
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 16.41%rr_BarChartHighestQuarterlyReturn
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Worst quarter:
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2008
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (22.74%)rr_BarChartLowestQuarterlyReturn
Performance Table Heading rr_PerformanceTableHeading AVERAGE ANNUAL TOTAL RETURNS For the Periods Ended December 31, 2014
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 performance is shown only for Institutional Class shares and after-tax returns for the Retirement Class shares will vary from the after-tax returns presented for the Institutional Class shares.
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.

 
Russell 1000® Growth Index (reflects no deductions for fees, expenses or taxes)
 
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 13.05%rr_AverageAnnualReturnYear01
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5 Years rr_AverageAnnualReturnYear05 15.81%rr_AverageAnnualReturnYear05
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10 Years rr_AverageAnnualReturnYear10 8.49%rr_AverageAnnualReturnYear10
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Retirement Class
 
Risk/Return: rr_RiskReturnAbstract  
Maximum Sales Charge Imposed on Purchases (percentage of offering price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge rr_MaximumDeferredSalesChargeOverOfferingPrice none
Maximum Sales Charge Imposed on Reinvested Dividends and Other Distributions rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther none
Redemption or Exchange Fee rr_RedemptionFeeOverRedemption none
Maximum Account Fee rr_MaximumAccountFeeOverAssets none
Management Fees rr_ManagementFeesOverAssets 0.04%rr_ManagementFeesOverAssets
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Other Expenses rr_OtherExpensesOverAssets 0.27%rr_OtherExpensesOverAssets
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Total Annual Fund Operating Expenses rr_ExpensesOverAssets 0.31%rr_ExpensesOverAssets
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Waivers and Expense Reimbursements rr_FeeWaiverOrReimbursementOverAssets    [1]
Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement rr_NetExpensesOverAssets 0.31%rr_NetExpensesOverAssets
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Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 32rr_ExpenseExampleYear01
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Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 100rr_ExpenseExampleYear03
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Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 174rr_ExpenseExampleYear05
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Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 393rr_ExpenseExampleYear10
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1 Year rr_AverageAnnualReturnYear01 12.73%rr_AverageAnnualReturnYear01
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5 Years rr_AverageAnnualReturnYear05 15.44%rr_AverageAnnualReturnYear05
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10 Years rr_AverageAnnualReturnYear10 8.12%rr_AverageAnnualReturnYear10
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Inception Date rr_AverageAnnualReturnInceptionDate Oct. 01, 2002
Institutional Class
 
Risk/Return: rr_RiskReturnAbstract  
Maximum Sales Charge Imposed on Purchases (percentage of offering price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge rr_MaximumDeferredSalesChargeOverOfferingPrice none
Maximum Sales Charge Imposed on Reinvested Dividends and Other Distributions rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther none
Redemption or Exchange Fee rr_RedemptionFeeOverRedemption none
Maximum Account Fee rr_MaximumAccountFeeOverAssets none
Management Fees rr_ManagementFeesOverAssets 0.04%rr_ManagementFeesOverAssets
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Other Expenses rr_OtherExpensesOverAssets 0.02%rr_OtherExpensesOverAssets
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Total Annual Fund Operating Expenses rr_ExpensesOverAssets 0.06%rr_ExpensesOverAssets
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Waivers and Expense Reimbursements rr_FeeWaiverOrReimbursementOverAssets    [1]
Total Annual Fund Operating Expenses After Fee Waiver and/or Expense Reimbursement rr_NetExpensesOverAssets 0.06%rr_NetExpensesOverAssets
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Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 6rr_ExpenseExampleYear01
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Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 19rr_ExpenseExampleYear03
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Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 34rr_ExpenseExampleYear05
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Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 77rr_ExpenseExampleYear10
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Annual Return 2005 rr_AnnualReturn2005 5.03%rr_AnnualReturn2005
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Annual Return 2006 rr_AnnualReturn2006 9.05%rr_AnnualReturn2006
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Annual Return 2007 rr_AnnualReturn2007 11.64%rr_AnnualReturn2007
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Annual Return 2008 rr_AnnualReturn2008 (38.46%)rr_AnnualReturn2008
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Annual Return 2009 rr_AnnualReturn2009 37.18%rr_AnnualReturn2009
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Annual Return 2010 rr_AnnualReturn2010 16.52%rr_AnnualReturn2010
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Annual Return 2011 rr_AnnualReturn2011 2.58%rr_AnnualReturn2011
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Annual Return 2012 rr_AnnualReturn2012 15.22%rr_AnnualReturn2012
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Annual Return 2013 rr_AnnualReturn2013 33.34%rr_AnnualReturn2013
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Annual Return 2014 rr_AnnualReturn2014 12.98%rr_AnnualReturn2014
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1 Year rr_AverageAnnualReturnYear01 12.98%rr_AverageAnnualReturnYear01
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5 Years rr_AverageAnnualReturnYear05 15.72%rr_AverageAnnualReturnYear05
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10 Years rr_AverageAnnualReturnYear10 8.40%rr_AverageAnnualReturnYear10
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Inception Date rr_AverageAnnualReturnInceptionDate Oct. 01, 2002
Institutional Class | After Taxes on Distributions
 
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 12.12%rr_AverageAnnualReturnYear01
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5 Years rr_AverageAnnualReturnYear05 15.29%rr_AverageAnnualReturnYear05
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10 Years rr_AverageAnnualReturnYear10 8.04%rr_AverageAnnualReturnYear10
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Institutional Class | After Taxes on Distributions and Sale of Fund Shares
 
Risk/Return: rr_RiskReturnAbstract  
1 Year rr_AverageAnnualReturnYear01 7.94%rr_AverageAnnualReturnYear01
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5 Years rr_AverageAnnualReturnYear05 12.69%rr_AverageAnnualReturnYear05
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10 Years rr_AverageAnnualReturnYear10 6.83%rr_AverageAnnualReturnYear10
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[1] Under the Fund's expense reimbursement arrangements, the Fund's investment adviser, Teachers Advisors, Inc., 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) 0.34% of average daily net assets for Retirement Class shares; and (ii) 0.09% of average daily net assets for Institutional Class shares of the Fund. These expense reimbursement arrangements will continue through at least February 29, 2016, unless changed with approval of the Board of Trustees.