485BPOS

As Filed with the U.S. Securities and Exchange Commission on November 19, 2013

1933 Act File No. 033-19589

1940 Act File No. 811-05447

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549
__________________
FORM N-1A
__________________
REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933	☒
Pre-Effective Amendment No.	☐
Post-Effective Amendment No. 66	☒
and/or
REGISTRATION STATEMENT UNDER THE INVESTMENT COMPANY ACT OF 1940	☒
Amendment No. 68	☒
(Check appropriate box or boxes.)
__________________
AMERICAN CENTURY QUANTITATIVE EQUITY FUNDS, INC. (Exact Name of Registrant as Specified in Charter)
__________________
4500 MAIN STREET, KANSAS CITY, MISSOURI 64111 (Address of Principal Executive Offices)(Zip Code)
REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: (816) 531-5575
CHARLES A. ETHERINGTON 4500 MAIN STREET, KANSAS CITY, MISSOURI 64111 (Name and Address of Agent for Service)
It is proposed that this filing will become effective (check appropriate box)

☒	immediately upon filing pursuant to paragraph (b)
☐	on (date) pursuant to paragraph (b)
☐	60 days after filing pursuant to paragraph (a)(1)
☐	on (date) pursuant to paragraph (a)(1)
☐	75 days after filing pursuant to paragraph (a)(2)
☐	on (date) pursuant to paragraph (a)(2) of rule 485.
If appropriate, check the following box:
☐	this post-effective amendment designates a new effective date for a previously filed post-effective amendment.

SIGNATURES

Pursuant to the requirements of the Securities Act and the Investment Company Act of 1940, the Registrant certifies that it meets all of the requirements for effectiveness of this Registration Statement amendment pursuant to Rule 485(b) promulgated under the Securities Act of 1933, as amended, and has duly caused this amendment to be signed on its behalf by the undersigned, duly authorized, in the City of Kansas City, State of Missouri on the 19th day of November, 2013.

American Century Quantitative Equity Funds, Inc.

(Registrant)

By:

*                                                                                  

Jonathan S. Thomas

President

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement amendment has been signed by the following persons in the capacities and on the dates indicated.

SIGNATURES	TITLE	DATE
* _________________________________ Jonathan S. Thomas	President and Director	November 19, 2013
* _________________________________ C. Jean Wade	Vice President, Treasurer and Chief Financial Officer	November 19, 2013
* _________________________________ Tanya S. Beder	Director	November 19, 2013
* _________________________________ Jeremy I. Bulow	Director	November 19, 2013
* _________________________________ Ronald J. Gilson	Chairman of the Board and Director	November 19, 2013
* _________________________________ Frederick L.A. Grauer	Director	November 19, 2013
* _________________________________ Peter F. Pervere	Director	November 19, 2013
* _________________________________ Myron S. Scholes	Director	November 19, 2013
* _________________________________ John B. Shoven	Director	November 19, 2013
*By:        /s/ Daniel K. Richardson Daniel K. Richardson Attorney in Fact

Pursuant to Power of Attorney, dated December 18, 2012 (filed electronically as Exhibit q1 to Post-Effective Amendment No. 51 to the Registration Statement of American Century California Tax-Free and Municipal Funds on December 28, 2012, File No. 2-82734, and incorporated herein by reference).

Secretary’s Certificate, dated December 18, 2012 (filed electronically as Exhibit q2 to Post-Effective Amendment No. 51 to the Registration Statement of American Century California Tax-Free and Municipal Funds on December 28, 2012, File No. 2-82734, and incorporated herein by reference).

EXHIBIT INDEX

EXHIBIT NUMBER	DESCRIPTION OF DOCUMENT
Exhibit – 101.INS	XBRL Instance Document
Exhibit – 101.SCH	XBRL Taxonomy Extension Schema Document
Exhibit – 101.DEF	XBRL Taxonomy Extension Definition Linkbase Document
Exhibit – 101.LAB	XBRL Taxonomy Extension Label Linkbase Document
Exhibit – 101.PRE	XBRL Taxonomy Extension Presentation Linkbase Document

XML

Label

Element

Value

Prospectus [Line Items]

rr_ProspectusLineItems

Document Type

dei_DocumentType

485BPOS

Document Period End Date

dei_DocumentPeriodEndDate

Jun. 30, 2013

Registrant Name

dei_EntityRegistrantName

AMERICAN CENTURY QUANTITATIVE EQUITY FUNDS, INC.

Central Index Key

dei_EntityCentralIndexKey

0000827060

Amendment Flag

dei_AmendmentFlag

false

Trading Symbol

dei_TradingSymbol

ACQEF

Document Creation Date

dei_DocumentCreationDate

Oct. 28, 2013

Document Effective Date

dei_DocumentEffectiveDate

Oct. 31, 2013

Prospectus Date

rr_ProspectusDate

Oct. 31, 2013

CORE EQUITY PLUS FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

CORE EQUITY PLUS 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

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 13 of the fund’s prospectus and Sales Charges in Appendix B of the 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 107% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

107.00%

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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 13 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

$ 50,000

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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, that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The managers use quantitative models to construct the portfolio of equity securities for the fund. The fund invests approximately 130% of its assets in long positions, while 30% of its assets are sold short. A long position arises when the fund buys a security outright. A short position arises when the fund sells a security it does not own but has borrowed in anticipation that the market price of the security will decline. If the market price in fact declines, the fund can replace the borrowed security at a lower price and capture the value represented by the difference between the higher sale price and the lower replacement price. The proceeds from the securities sold short are used to purchase an additional 30% of long positions. The net investment exposure for the fund is a 100% long market exposure.

The portfolio managers buy, or take long positions in, equity securities that they have identified as the most attractive and take short positions in equity securities that they have identified as the least attractive using a multi-factor quantitative model in a two-step process. In the first step, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from the most attractive to least attractive based on an objective set of measures, including a stock’s value, quality, growth, and momentum. In the second step, the managers use a quantitative model to build a portfolio that provides the optimal balance between risk and expected return.

The portfolio managers generally sell a stock from the fund's long portfolio when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

The fund’s use of short selling as a primary investment strategy creates leverage in an attempt to increase returns.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Short Sales Risk - If the market price of a security increases after the fund borrows the security, the fund may suffer a loss when it replaces the borrowed security at the higher price. Any loss will be increased by the amount of compensation, interest or dividends, and transaction costs the fund must pay to the lender of the borrowed security.

• Leverage Risk - The fund’s investment strategy utilizes leverage, which can increase market exposure and subject the fund to greater risk and higher volatility.

• Overweighting Risk - If the fund is overweighted in a stock or sector, any negative development related to that stock or sector will have a greater impact on the fund than other funds that are not overweighted in that stock or sector.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the S&P 500^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) 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 risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Performance Quarter (1Q 2012): 13.42%  

Lowest Performance Quarter (2Q 2012): -4.00%

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was 21.70%.

Year to Date Return, Label

rr_YearToDateReturnLabel

Investor Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

21.70%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

13.42%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Jun. 30, 2012

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(4.00%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

CORE EQUITY PLUS FUND | S&P 500® Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

16.00%

Since Inception

rr_AverageAnnualReturnSinceInception

14.35%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

CORE EQUITY PLUS FUND | INVESTOR CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

25

Management Fee

rr_ManagementFeesOverAssets

1.30%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

0.32%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.25%

Other

rr_Component3OtherExpensesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.57%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.87%

1 year

rr_ExpenseExampleYear01

190

3 years

rr_ExpenseExampleYear03

589

5 years

rr_ExpenseExampleYear05

1,012

10 years

rr_ExpenseExampleYear10

2,188

Annual Return 2012

rr_AnnualReturn2012

16.43%

1 year

rr_AverageAnnualReturnYear01

16.43%

Since Inception

rr_AverageAnnualReturnSinceInception

13.05%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

CORE EQUITY PLUS FUND | INVESTOR CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

15.87%

Since Inception

rr_AverageAnnualReturnSinceInception

12.58%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

CORE EQUITY PLUS FUND | INVESTOR CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

11.10%

Since Inception

rr_AverageAnnualReturnSinceInception

10.99%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

CORE EQUITY PLUS FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.10%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

0.32%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.25%

Other

rr_Component3OtherExpensesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.57%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.67%

1 year

rr_ExpenseExampleYear01

170

3 years

rr_ExpenseExampleYear03

527

5 years

rr_ExpenseExampleYear05

908

10 years

rr_ExpenseExampleYear10

1,974

1 year

rr_AverageAnnualReturnYear01

16.66%

Since Inception

rr_AverageAnnualReturnSinceInception

13.28%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

CORE EQUITY PLUS FUND | A CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

^[1]

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.30%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

0.32%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.25%

Other

rr_Component3OtherExpensesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.57%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.12%

1 year

rr_ExpenseExampleYear01

778

3 years

rr_ExpenseExampleYear03

1,202

5 years

rr_ExpenseExampleYear05

1,649

10 years

rr_ExpenseExampleYear10

2,882

1 year

rr_AverageAnnualReturnYear01

9.51%

Since Inception

rr_AverageAnnualReturnSinceInception

7.21%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

CORE EQUITY PLUS FUND | C CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.30%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

0.32%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.25%

Other

rr_Component3OtherExpensesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.57%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.87%

1 year

rr_ExpenseExampleYear01

291

3 years

rr_ExpenseExampleYear03

890

5 years

rr_ExpenseExampleYear05

1,514

10 years

rr_ExpenseExampleYear10

3,188

1 year

rr_AverageAnnualReturnYear01

15.35%

Since Inception

rr_AverageAnnualReturnSinceInception

11.92%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

CORE EQUITY PLUS FUND | R CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.30%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

0.32%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.25%

Other

rr_Component3OtherExpensesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.57%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.37%

1 year

rr_ExpenseExampleYear01

241

3 years

rr_ExpenseExampleYear03

741

5 years

rr_ExpenseExampleYear05

1,266

10 years

rr_ExpenseExampleYear10

2,702

1 year

rr_AverageAnnualReturnYear01

15.88%

Since Inception

rr_AverageAnnualReturnSinceInception

12.45%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

DISCIPLINED GROWTH PLUS FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

DISCIPLINED GROWTH PLUS 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

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 13 of the fund’s prospectus and Sales Charges in Appendix B of the 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 100% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

100.00%

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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 13 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

50,000

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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, that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The managers use quantitative models to construct the portfolio of equity securities for the fund. The fund invests approximately 130% of its assets in long positions, while 30% of its assets are sold short. A long position arises when the fund buys a security outright. A short position arises when the fund sells a security it does not own but has borrowed in anticipation that the market price of the security will decline. If the market price in fact declines, the fund can replace the borrowed security at a lower price and capture the value represented by the difference between the higher sale price and the lower replacement price. The proceeds from the securities sold short are used to fund the purchase of the additional 30% of long positions. The net investment exposure for the fund is a 100% long market exposure.

The portfolio managers initially identify an eligible universe of growth stocks and then buy, or take long positions in, equity securities that they have identified as the most attractive and take short positions in equity securities that they have identified as the least attractive using a multi-factor quantitative model in a two-step process. In the first step, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from most to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. In the second step, the managers use a quantitative model to build a portfolio that provides the optimal balance between risk and expected return.

The portfolio managers generally sell a stock from the fund's long portfolio when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

The fund’s use of short selling as a primary investment strategy creates leverage in an attempt to increase returns.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Short Sales Risk - If the market price of a security increases after the fund borrows the security, the fund may suffer a loss when it replaces the borrowed security at the higher price. Any loss will be increased by the amount of compensation, interest or dividends, and transaction costs the fund must pay to the lender of the borrowed security.

• Leverage Risk - The fund’s investment strategy utilizes leverage, which can increase market exposure and subject the fund to greater risk and higher volatility.

• Overweighting Risk - If the fund is overweighted in a stock or sector, any negative development related to that stock or sector will have a greater impact on the fund than other funds that are not overweighted in that stock or sector.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the Russell 1000^® Growth Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Growth Stocks - Investments in growth stocks may involve special risks and their prices tend to fluctuate more dramatically than the overall stock market.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) 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 risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Performance Quarter (1Q 2012): 17.14%  

Lowest Performance Quarter (2Q 2012): -5.40%

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was 22.09%.

Year to Date Return, Label

rr_YearToDateReturnLabel

Investor Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

22.09%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.14%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Jun. 30, 2012

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(5.40%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

DISCIPLINED GROWTH PLUS FUND | Russell 1000® Growth Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

15.26%

Since Inception

rr_AverageAnnualReturnSinceInception

12.62%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

DISCIPLINED GROWTH PLUS FUND | INVESTOR CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

25

Management Fee

rr_ManagementFeesOverAssets

1.45%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

0.17%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.24%

Other

rr_Component3OtherExpensesOverAssets

0.01%

Other Expenses

rr_OtherExpensesOverAssets

0.42%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.87%

1 year

rr_ExpenseExampleYear01

190

3 years

rr_ExpenseExampleYear03

589

5 years

rr_ExpenseExampleYear05

1,012

10 years

rr_ExpenseExampleYear10

2,188

Annual Return 2012

rr_AnnualReturn2012

15.66%

1 year

rr_AverageAnnualReturnYear01

15.66%

Since Inception

rr_AverageAnnualReturnSinceInception

11.42%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

DISCIPLINED GROWTH PLUS FUND | INVESTOR CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

15.56%

Since Inception

rr_AverageAnnualReturnSinceInception

11.32%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

DISCIPLINED GROWTH PLUS FUND | INVESTOR CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

10.31%

Since Inception

rr_AverageAnnualReturnSinceInception

9.72%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

DISCIPLINED GROWTH PLUS FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.25%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

0.17%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.24%

Other

rr_Component3OtherExpensesOverAssets

0.01%

Other Expenses

rr_OtherExpensesOverAssets

0.42%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.67%

1 year

rr_ExpenseExampleYear01

170

3 years

rr_ExpenseExampleYear03

527

5 years

rr_ExpenseExampleYear05

908

10 years

rr_ExpenseExampleYear10

1,974

1 year

rr_AverageAnnualReturnYear01

15.89%

Since Inception

rr_AverageAnnualReturnSinceInception

11.64%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

DISCIPLINED GROWTH PLUS FUND | A CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

^[1]

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.45%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

0.17%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.24%

Other

rr_Component3OtherExpensesOverAssets

0.01%

Other Expenses

rr_OtherExpensesOverAssets

0.42%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.12%

1 year

rr_ExpenseExampleYear01

778

3 years

rr_ExpenseExampleYear03

1,202

5 years

rr_ExpenseExampleYear05

1,649

10 years

rr_ExpenseExampleYear10

2,882

1 year

rr_AverageAnnualReturnYear01

8.72%

Since Inception

rr_AverageAnnualReturnSinceInception

5.66%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

DISCIPLINED GROWTH PLUS FUND | C CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.45%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

0.17%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.24%

Other

rr_Component3OtherExpensesOverAssets

0.01%

Other Expenses

rr_OtherExpensesOverAssets

0.42%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.87%

1 year

rr_ExpenseExampleYear01

291

3 years

rr_ExpenseExampleYear03

890

5 years

rr_ExpenseExampleYear05

1,514

10 years

rr_ExpenseExampleYear10

3,188

1 year

rr_AverageAnnualReturnYear01

14.50%

Since Inception

rr_AverageAnnualReturnSinceInception

10.26%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

DISCIPLINED GROWTH PLUS FUND | R CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.45%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

0.17%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.24%

Other

rr_Component3OtherExpensesOverAssets

0.01%

Other Expenses

rr_OtherExpensesOverAssets

0.42%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.37%

1 year

rr_ExpenseExampleYear01

241

3 years

rr_ExpenseExampleYear03

741

5 years

rr_ExpenseExampleYear05

1,266

10 years

rr_ExpenseExampleYear10

2,702

1 year

rr_AverageAnnualReturnYear01

15.09%

Since Inception

rr_AverageAnnualReturnSinceInception

10.87%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 31, 2011

DISCIPLINED GROWTH FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

DISCIPLINED 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

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 13 of the fund’s prospectus and Sales Charges in Appendix B of the 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 94% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

94.00%

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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 13 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

50,000

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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, that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

In selecting stocks for the fund, the portfolio managers initially identify an eligible universe of growth stocks then use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk- Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the Russell 1000^® Growth Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Growth Stocks - Investments in growth stocks may involve special risks and their prices tend to fluctuate more dramatically than the overall stock market.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) 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 risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Performance Quarter (1Q 2012): 17.16%  

Lowest Performance Quarter (4Q 2008): -23.62%  

As of September 30, 2013, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 21.84%.

Year to Date Return, Label

rr_YearToDateReturnLabel

Investor Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

21.84%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.16%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(23.62%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

DISCIPLINED GROWTH FUND | Russell 1000® Growth Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

15.26%

5 years

rr_AverageAnnualReturnYear05

3.12%

Since Inception

rr_AverageAnnualReturnSinceInception

5.41%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

DISCIPLINED GROWTH FUND | INVESTOR CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

25

Management Fee

rr_ManagementFeesOverAssets

1.02%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

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

Annual Return 2006

rr_AnnualReturn2006

11.30%

Annual Return 2007

rr_AnnualReturn2007

11.24%

Annual Return 2008

rr_AnnualReturn2008

(41.18%)

Annual Return 2009

rr_AnnualReturn2009

35.02%

Annual Return 2010

rr_AnnualReturn2010

22.17%

Annual Return 2011

rr_AnnualReturn2011

2.49%

Annual Return 2012

rr_AnnualReturn2012

15.72%

1 year

rr_AverageAnnualReturnYear01

15.72%

5 years

rr_AverageAnnualReturnYear05

2.84%

Since Inception

rr_AverageAnnualReturnSinceInception

5.69%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

DISCIPLINED GROWTH FUND | INVESTOR CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

15.56%

5 years

rr_AverageAnnualReturnYear05

2.76%

Since Inception

rr_AverageAnnualReturnSinceInception

5.46%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

DISCIPLINED GROWTH FUND | INVESTOR CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

10.42%

5 years

rr_AverageAnnualReturnYear05

2.42%

Since Inception

rr_AverageAnnualReturnSinceInception

4.86%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

DISCIPLINED GROWTH FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.82%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.83%

1 year

rr_ExpenseExampleYear01

85

3 years

rr_ExpenseExampleYear03

265

5 years

rr_ExpenseExampleYear05

461

10 years

rr_ExpenseExampleYear10

1,026

1 year

rr_AverageAnnualReturnYear01

15.91%

5 years

rr_AverageAnnualReturnYear05

3.06%

Since Inception

rr_AverageAnnualReturnSinceInception

5.90%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

DISCIPLINED GROWTH FUND | A CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

^[1]

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.02%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.28%

1 year

rr_ExpenseExampleYear01

698

3 years

rr_ExpenseExampleYear03

958

5 years

rr_ExpenseExampleYear05

1,238

10 years

rr_ExpenseExampleYear10

2,031

1 year

rr_AverageAnnualReturnYear01

8.86%

^[2]

5 years

rr_AverageAnnualReturnYear05

1.40%

^[2]

Since Inception

rr_AverageAnnualReturnSinceInception

4.58%

^[2]

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

^[2]

DISCIPLINED GROWTH FUND | C CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.02%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.03%

1 year

rr_ExpenseExampleYear01

207

3 years

rr_ExpenseExampleYear03

638

5 years

rr_ExpenseExampleYear05

1,094

10 years

rr_ExpenseExampleYear10

2,355

1 year

rr_AverageAnnualReturnYear01

14.61%

5 years

rr_AverageAnnualReturnYear05

1.83%

Since Inception

rr_AverageAnnualReturnSinceInception

1.56%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 28, 2007

DISCIPLINED GROWTH FUND | R CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.02%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.53%

1 year

rr_ExpenseExampleYear01

156

3 years

rr_ExpenseExampleYear03

484

5 years

rr_ExpenseExampleYear05

835

10 years

rr_ExpenseExampleYear10

1,822

1 year

rr_AverageAnnualReturnYear01

15.12%

5 years

rr_AverageAnnualReturnYear05

2.34%

Since Inception

rr_AverageAnnualReturnSinceInception

5.17%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

EMERGING MARKETS VALUE FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

EMERGING MARKETS VALUE FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital growth.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the 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. Because the fund is new, the fund’s portfolio turnover is not available.

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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

50,000

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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 (unless otherwise indicated), that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

In selecting stocks for the fund, the portfolio managers select primarily from publicly-traded companies of all sizes located in the emerging market countries that comprise the MSCI Emerging Markets Index.

The MSCI Emerging Markets Index is a market capitalization-weighted index that monitors, as of the date of this prospectus, the performance of value stocks in the following emerging markets countries: Brazil, Chile, China, Colombia, Czech Republic, Egypt, Greece, Hungary, India, Indonesia, Korea, Malaysia, Mexico, Peru, Philippines, Poland, Russia, South Africa, Taiwan, Thailand and Turkey.

The managers use quantitative models in a two-step process to construct the portfolio of stocks for the fund. First, the managers rank stocks from most attractive to least attractive based on each stock’s value, momentum, and quality, as well as its growth potential. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Under normal market conditions, at least 80% of the fund's net assets will be invested in emerging market securities.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Foreign Securities Risk - The fund invests primarily in foreign securities, which are generally riskier than U.S. securities. As a result, the fund is subject to foreign risk, meaning that political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), and natural disasters occurring in a country where the fund invests could cause the fund’s investments in that country to experience gains or losses. Because of these risks, and others, securities of foreign issuers may be less liquid, more volatile, and harder to value than U.S. securities.

• Emerging Market Risk - Investing in securities of companies located in emerging market countries generally is also riskier than investing in securities of companies located in foreign developed countries. Emerging market countries may have unstable governments and/or economies that are subject to sudden change. These changes may be magnified by the countries’ emergent financial markets, resulting in significant volatility to investments in these countries. These countries also may lack the legal, business and social framework to support securities markets.

• Currency Risk - Because the fund generally invests in securities denominated in foreign currencies, the fund is subject to currency risk, meaning that the fund could experience gains or losses based solely on changes in the exchange rate between foreign currencies and the U.S. dollar.

• Style Risk - If at any time the market is not favoring the fund’s value or quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Benchmark Correlation - The fund’s performance will likely be similar to the performance of its benchmark, the MSCI Emerging Markets Value Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Quantitative Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers’ judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors’ historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Small and Mid Cap Stocks - The fund may invest in mid-sized and smaller companies, which may be more volatile and subject to greater risk than larger companies. Smaller companies may have limited financial resources, product lines and markets, and their securities may trade less frequently and in more limited volumes than the securities of larger companies, which could lead to higher transaction costs.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

rr_BarChartAndPerformanceTableHeading

Fund Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The fund’s performance history is not available as of the date of this prospectus. When the fund has investment results for a full calendar year, this section will feature charts that show annual total returns, highest and lowest quarterly returns and average annual total returns for the fund. This information indicates the volatility of the fund’s historical returns from year to year.

Performance information is designed to help you see how fund returns can vary. Keep in mind that past performance (before and after taxes) does not predict how the fund will perform in the future.

For current performance information, please visit americancentury.com.

Performance One Year or Less [Text]

rr_PerformanceOneYearOrLess

The fund's performance history is not available as of the date of this prospectus. When the fund has investment results for a full calendar year, this section will feature charts that show annual total returns, highest and lowest quarterly returns and average annual total returns for the fund.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

Performance Past Does Not Indicate Future [Text]

rr_PerformancePastDoesNotIndicateFuture

Keep in mind that past performance (before and after taxes) does not predict how the fund will perform in the future.

EMERGING MARKETS VALUE FUND | INVESTOR CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

25

Management Fee

rr_ManagementFeesOverAssets

1.52%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

^[3]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.53%

Fee Waiver or Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.07%

^[4]

Total Annual Fund Operating Expenses After Waiver

rr_NetExpensesOverAssets

1.46%

Other Expenses, New Fund, Based on Estimates [Text]

rr_OtherExpensesNewFundBasedOnEstimates

Other Expenses are based on estimated amounts for the current fiscal year.

1 year

rr_ExpenseExampleYear01

149

3 years

rr_ExpenseExampleYear03

477

EMERGING MARKETS VALUE FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.32%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

^[3]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.33%

Fee Waiver or Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.07%

^[4]

Total Annual Fund Operating Expenses After Waiver

rr_NetExpensesOverAssets

1.26%

Other Expenses, New Fund, Based on Estimates [Text]

rr_OtherExpensesNewFundBasedOnEstimates

Other Expenses are based on estimated amounts for the current fiscal year.

1 year

rr_ExpenseExampleYear01

129

3 years

rr_ExpenseExampleYear03

415

EMERGING MARKETS VALUE FUND | A CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

^[1]

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.52%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

^[3]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.78%

Fee Waiver or Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.07%

^[4]

Total Annual Fund Operating Expenses After Waiver

rr_NetExpensesOverAssets

1.71%

Other Expenses, New Fund, Based on Estimates [Text]

rr_OtherExpensesNewFundBasedOnEstimates

Other Expenses are based on estimated amounts for the current fiscal year.

1 year

rr_ExpenseExampleYear01

739

3 years

rr_ExpenseExampleYear03

1,097

EMERGING MARKETS VALUE FUND | C CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.52%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

^[3]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.53%

Fee Waiver or Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.07%

^[4]

Total Annual Fund Operating Expenses After Waiver

rr_NetExpensesOverAssets

2.46%

Other Expenses, New Fund, Based on Estimates [Text]

rr_OtherExpensesNewFundBasedOnEstimates

Other Expenses are based on estimated amounts for the current fiscal year.

1 year

rr_ExpenseExampleYear01

250

3 years

rr_ExpenseExampleYear03

782

EMERGING MARKETS VALUE FUND | R CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.52%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

^[3]

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.03%

Fee Waiver or Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.07%

^[4]

Total Annual Fund Operating Expenses After Waiver

rr_NetExpensesOverAssets

1.96%

Other Expenses, New Fund, Based on Estimates [Text]

rr_OtherExpensesNewFundBasedOnEstimates

Other Expenses are based on estimated amounts for the current fiscal year.

1 year

rr_ExpenseExampleYear01

199

3 years

rr_ExpenseExampleYear03

631

EQUITY MARKET NEUTRAL FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

EQUITY MARKET NEUTRAL FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks capital appreciation independent of equity market conditions.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 14 of the fund’s prospectus and Sales Charges in Appendix B of the 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 222% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

222.00%

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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 14 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

50,000

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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, that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The managers use quantitative models to construct the portfolio for the fund. The portfolio managers buy, or take long positions in, equity securities that they have identified as undervalued. They take short positions in equity securities that they have identified as overvalued.  A short position arises when the fund sells a security it does not own but has borrowed in anticipation that the market price of the security will decline. If the market price in fact declines, the fund can replace the borrowed security at a lower price and capture the value represented by the difference between the higher sale price and the lower replacement price. The fund’s investment process is designed to maintain approximately equal dollar amounts invested in long and short positions at all times. By employing this market neutral strategy, the fund seeks to limit market risk (the effects of general market movements on the fund’s performance). A market neutral strategy seeks to limit the fund’s volatility relative to the market. As a result of this strategy, the portfolio’s price movements are not expected to correlate with the market’s price movements.

In selecting stocks for the fund, the portfolio managers use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily publicly traded U.S. companies with a market capitalization greater than $1 billion, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity, or specific events alter its prospects.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Management Risk - Although the fund seeks to have approximately equal dollar amounts invested in long and short positions and a neutral exposure to market movements, there is a risk that the portfolio managers will not be able to construct a portfolio of long and short positions that has limited exposure to general market movements.

• Investment Process Risk- Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Failure to Maintain Market Neutrality - Though the fund seeks to limit risks associated with investing in the general equity market, external conditions may impact the fund’s performance. In addition, although the portfolio managers intend to construct a market neutral portfolio, there is a risk that the portfolio managers will not construct a portfolio that limits exposure to general market movements.

• Style Risk - Because the fund’s portfolio may not always be style-neutral, its performance may be sensitive to the value/growth cycle within the U.S. equity markets. Also, if at any time the market is not favoring the fund’s quantitative style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Short Sales Risk - If the market price of a security increases after the fund borrows the security, the fund may suffer a loss when it replaces the borrowed security at the higher price. Any loss will be increased by the amount of compensation, interest or dividends, and transaction costs the fund must pay to a lender of the security.

• Overweighting Risk - If the fund is overweighted in a stock or sector, any negative development related to that stock or sector will have a greater impact on the fund than other funds that are not overweighted in that stock or sector.

• Small Cap Stocks - Though the fund invests primarily in larger companies, it may also invest in smaller companies. Investments in smaller companies may be more volatile and subject to greater risk than larger companies. Smaller companies may have limited financial resources, product lines and markets, and their securities may trade less frequently and in more limited volumes than the securities of larger companies, which could lead to higher transaction costs.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities the fund owns in its long portfolio or in which the fund has taken a short position.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time, your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) 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 risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Performance Quarter (2Q 2006): 10.73% 

Lowest Performance Quarter (3Q 2008): -6.78%

As of September 30, 2013, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 3.43%.

Year to Date Return, Label

rr_YearToDateReturnLabel

Investor Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

3.43%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2006

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

10.73%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(6.78%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

EQUITY MARKET NEUTRAL FUND | Barclays U.S. 1-3 Month Treasury Bill Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

0.08%

5 years

rr_AverageAnnualReturnYear05

0.44%

Since Inception

rr_AverageAnnualReturnSinceInception

1.73%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

EQUITY MARKET NEUTRAL FUND | INVESTOR CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

25

Management Fee

rr_ManagementFeesOverAssets

1.38%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

1.41%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.27%

Other

rr_Component3OtherExpensesOverAssets

0.01%

Other Expenses

rr_OtherExpensesOverAssets

1.69%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

3.07%

1 year

rr_ExpenseExampleYear01

311

3 years

rr_ExpenseExampleYear03

950

5 years

rr_ExpenseExampleYear05

1,612

10 years

rr_ExpenseExampleYear10

3,376

Annual Return 2006

rr_AnnualReturn2006

5.08%

Annual Return 2007

rr_AnnualReturn2007

7.85%

Annual Return 2008

rr_AnnualReturn2008

(2.55%)

Annual Return 2009

rr_AnnualReturn2009

(7.75%)

Annual Return 2010

rr_AnnualReturn2010

1.72%

Annual Return 2011

rr_AnnualReturn2011

5.87%

Annual Return 2012

rr_AnnualReturn2012

(1.22%)

1 year

rr_AverageAnnualReturnYear01

(1.22%)

5 years

rr_AverageAnnualReturnYear05

(0.89%)

Since Inception

rr_AverageAnnualReturnSinceInception

1.07%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

EQUITY MARKET NEUTRAL FUND | INVESTOR CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

(1.22%)

5 years

rr_AverageAnnualReturnYear05

(0.89%)

Since Inception

rr_AverageAnnualReturnSinceInception

0.97%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

EQUITY MARKET NEUTRAL FUND | INVESTOR CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

(0.79%)

5 years

rr_AverageAnnualReturnYear05

(0.75%)

Since Inception

rr_AverageAnnualReturnSinceInception

0.88%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

EQUITY MARKET NEUTRAL FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.18%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

1.41%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.27%

Other

rr_Component3OtherExpensesOverAssets

0.01%

Other Expenses

rr_OtherExpensesOverAssets

1.69%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.87%

1 year

rr_ExpenseExampleYear01

291

3 years

rr_ExpenseExampleYear03

890

5 years

rr_ExpenseExampleYear05

1,514

10 years

rr_ExpenseExampleYear10

3,188

1 year

rr_AverageAnnualReturnYear01

(1.12%)

5 years

rr_AverageAnnualReturnYear05

(0.70%)

Since Inception

rr_AverageAnnualReturnSinceInception

1.27%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

EQUITY MARKET NEUTRAL FUND | A CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

^[1]

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.38%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

1.41%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.27%

Other

rr_Component3OtherExpensesOverAssets

0.01%

Other Expenses

rr_OtherExpensesOverAssets

1.69%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

3.32%

1 year

rr_ExpenseExampleYear01

891

3 years

rr_ExpenseExampleYear03

1,539

5 years

rr_ExpenseExampleYear05

2,208

10 years

rr_ExpenseExampleYear10

3,972

1 year

rr_AverageAnnualReturnYear01

(7.25%)

5 years

rr_AverageAnnualReturnYear05

(2.33%)

Since Inception

rr_AverageAnnualReturnSinceInception

none

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

EQUITY MARKET NEUTRAL FUND | C CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.38%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

1.41%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.27%

Other

rr_Component3OtherExpensesOverAssets

0.01%

Other Expenses

rr_OtherExpensesOverAssets

1.69%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

4.07%

1 year

rr_ExpenseExampleYear01

410

3 years

rr_ExpenseExampleYear03

1,240

5 years

rr_ExpenseExampleYear05

2,084

10 years

rr_ExpenseExampleYear10

4,254

1 year

rr_AverageAnnualReturnYear01

(2.27%)

5 years

rr_AverageAnnualReturnYear05

(1.89%)

Since Inception

rr_AverageAnnualReturnSinceInception

0.06%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

EQUITY MARKET NEUTRAL FUND | R CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.38%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

1.41%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.27%

Other

rr_Component3OtherExpensesOverAssets

0.01%

Other Expenses

rr_OtherExpensesOverAssets

1.69%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

3.57%

1 year

rr_ExpenseExampleYear01

361

3 years

rr_ExpenseExampleYear03

1,096

5 years

rr_ExpenseExampleYear05

1,851

10 years

rr_ExpenseExampleYear10

3,827

1 year

rr_AverageAnnualReturnYear01

(1.73%)

5 years

rr_AverageAnnualReturnYear05

(1.39%)

Since Inception

rr_AverageAnnualReturnSinceInception

0.57%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 30, 2005

EQUITY GROWTH FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

EQUITY GROWTH FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks long-term capital growth by investing in common stocks.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the 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 94% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

94.00%

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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

50,000

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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, that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

In selecting stocks for the fund, the portfolio managers use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

Under normal market conditions, at least 80% of the fund’s net assets will be invested in equity securities.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk- Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the S&P 500^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) 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 risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Performance Quarter (2Q 2003): 15.14% 

Lowest Performance Quarter (4Q 2008): -21.63%

As of September 30, 2013, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 19.72%.

Year to Date Return, Label

rr_YearToDateReturnLabel

Investor Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

19.72%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2003

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

15.14%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(21.63%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

EQUITY GROWTH FUND | S&P 500® Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

16.00%

5 years

rr_AverageAnnualReturnYear05

1.66%

10 years

rr_AverageAnnualReturnYear10

7.10%

EQUITY GROWTH FUND | INVESTOR CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

25

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.68%

1 year

rr_ExpenseExampleYear01

70

3 years

rr_ExpenseExampleYear03

218

5 years

rr_ExpenseExampleYear05

379

10 years

rr_ExpenseExampleYear10

847

Annual Return 2003

rr_AnnualReturn2003

30.27%

Annual Return 2004

rr_AnnualReturn2004

13.98%

Annual Return 2005

rr_AnnualReturn2005

7.30%

Annual Return 2006

rr_AnnualReturn2006

14.14%

Annual Return 2007

rr_AnnualReturn2007

3.42%

Annual Return 2008

rr_AnnualReturn2008

(34.74%)

Annual Return 2009

rr_AnnualReturn2009

20.04%

Annual Return 2010

rr_AnnualReturn2010

14.90%

Annual Return 2011

rr_AnnualReturn2011

4.06%

Annual Return 2012

rr_AnnualReturn2012

16.32%

1 year

rr_AverageAnnualReturnYear01

16.32%

5 years

rr_AverageAnnualReturnYear05

1.73%

10 years

rr_AverageAnnualReturnYear10

7.43%

Inception Date

rr_AverageAnnualReturnInceptionDate

May 09, 1991

EQUITY GROWTH FUND | INVESTOR CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

16.00%

5 years

rr_AverageAnnualReturnYear05

1.50%

10 years

rr_AverageAnnualReturnYear10

7.02%

Inception Date

rr_AverageAnnualReturnInceptionDate

May 09, 1991

EQUITY GROWTH FUND | INVESTOR CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

11.01%

5 years

rr_AverageAnnualReturnYear05

1.43%

10 years

rr_AverageAnnualReturnYear10

6.49%

Inception Date

rr_AverageAnnualReturnInceptionDate

May 09, 1991

EQUITY GROWTH FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.47%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.48%

1 year

rr_ExpenseExampleYear01

49

3 years

rr_ExpenseExampleYear03

154

5 years

rr_ExpenseExampleYear05

269

10 years

rr_ExpenseExampleYear10

604

1 year

rr_AverageAnnualReturnYear01

16.54%

5 years

rr_AverageAnnualReturnYear05

1.93%

10 years

rr_AverageAnnualReturnYear10

7.64%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jan. 02, 1998

EQUITY GROWTH FUND | A CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

^[1]

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.93%

1 year

rr_ExpenseExampleYear01

665

3 years

rr_ExpenseExampleYear03

855

5 years

rr_ExpenseExampleYear05

1,061

10 years

rr_ExpenseExampleYear10

1,652

1 year

rr_AverageAnnualReturnYear01

9.31%

^[2]

5 years

rr_AverageAnnualReturnYear05

0.28%

^[2]

10 years

rr_AverageAnnualReturnYear10

6.54%

^[2]

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 09, 1997

^[2]

EQUITY GROWTH FUND | C CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.68%

1 year

rr_ExpenseExampleYear01

171

3 years

rr_ExpenseExampleYear03

530

5 years

rr_ExpenseExampleYear05

913

10 years

rr_ExpenseExampleYear10

1,985

1 year

rr_AverageAnnualReturnYear01

15.14%

5 years

rr_AverageAnnualReturnYear05

0.72%

10 years

rr_AverageAnnualReturnYear10

6.39%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 18, 2001

EQUITY GROWTH FUND | R CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.18%

1 year

rr_ExpenseExampleYear01

121

3 years

rr_ExpenseExampleYear03

375

5 years

rr_ExpenseExampleYear05

650

10 years

rr_ExpenseExampleYear10

1,431

1 year

rr_AverageAnnualReturnYear01

15.75%

5 years

rr_AverageAnnualReturnYear05

1.22%

Since Inception

rr_AverageAnnualReturnSinceInception

3.12%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 29, 2005

GLOBAL GOLD FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

GLOBAL GOLD FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks to realize a total return (capital growth and dividends) consistent with investment in securities of companies that are engaged in mining, processing, fabricating or distributing gold or other precious metals throughout the world.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the 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 6% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

6.00%

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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

50,000

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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 (unless otherwise indicated), that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The fund invests at least 80% of its net assets in companies that are engaged in mining, processing, fabricating, distributing, exploring for or otherwise dealing in gold. The portfolio managers use quantitative management techniques and fundamental stock selection in a two-step process to construct the portfolio of stocks for the fund. First, the managers select stocks based on several valuation criteria, without comparing the fund’s holdings to the holdings of an index or benchmark. Second, the managers use a quantitative model to assess the fund’s risk characteristics relative to its benchmark and help the managers build a portfolio of stocks that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

The fund invests at least 80% of its net assets in companies that are engaged in mining, processing, fabricating, distributing, exploring for or otherwise dealing in gold. The fund concentrates its investments in a specific area and therefore may be subject to greater risks and market fluctuations than a portfolio representing a broader range of industries.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Gold Stocks - Gold stocks are generally considered speculative because of high share price volatility. The price of gold will likely impact the value of the companies in which the fund invests. The price of gold will fluctuate, sometimes considerably. Though many investors believe that gold investments hedge against inflation, currency devaluations and stock market declines, there is no guarantee that these historical inverse relationships will continue.

• Nondiversification - The fund is classified as nondiversified. A nondiversified fund may invest a greater percentage of its assets in a smaller number of securities than a diversified fund. This gives the managers the flexibility to hold large positions in a small number of securities. If so, a price change in any one of those securities may have a greater impact on the fund's share price than would be the case in a diversified fund and the fund may be more volatile than if it was diversified.

• Concentration Risk - The fund concentrates its investments in a specific area and therefore may be subject to greater risks and market fluctuations than a portfolio representing a broader range of industries.

• Foreign Securities Risk - The fund invests primarily in foreign securities, which are generally riskier than U.S. stocks. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.

• Emerging Markets Risk -Investing in securities of companies located in emerging market countries generally is riskier than investing in securities of companies located in foreign developed countries.

• Currency Risk - Because the fund invests in securities denominated in foreign currencies, the fund is subject to currency risk, meaning that the fund could experience gains or losses based solely on changes in the exchange rate between foreign currencies and the U.S. dollar.

• Market Risk - The value of the fund's shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund's shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

Nondiversification - The fund is classified as nondiversified. A nondiversified fund may invest a greater percentage of its assets in a smaller number of securities than a diversified fund. This gives the managers the flexibility to hold large positions in a small number of securities. If so, a price change in any one of those securities may have a greater impact on the fund's share price than would be the case in a diversified fund and the fund may be more volatile than if it was diversified.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) 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 risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The table also shows returns for the NYSE Arca Gold Miners Index, which is a modified market capitalization-weighted index comprised of publicly traded companies involved primarily in mining for gold and silver. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Additional Market Index [Text]

rr_PerformanceAdditionalMarketIndex

The table also shows returns for the NYSE Arca Gold Miners Index, which is a modified market capitalization-weighted index comprised of publicly traded companies involved primarily in mining for gold and silver.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Performance Quarter (3Q 2012): 22.78%  

Lowest Performance Quarter (3Q 2008): -29.72%

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was -42.96%.

Year to Date Return, Label

rr_YearToDateReturnLabel

Investor Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(42.96%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

22.78%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(29.72%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

GLOBAL GOLD FUND | MSCI World Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

15.83%

5 years

rr_AverageAnnualReturnYear05

(1.18%)

10 years

rr_AverageAnnualReturnYear10

7.51%

GLOBAL GOLD FUND | NYSE Arca Gold Miners Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

(8.46%)

^[5]

5 years

rr_AverageAnnualReturnYear05

1.16%

^[5]

GLOBAL GOLD FUND | INVESTOR CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Redemption/Exchange Fee (as a percentage of amount redeemed/exchanged for shares held less than 60 days)

rr_RedemptionFeeOverRedemption

(1.00%)

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

25

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.68%

1 year

rr_ExpenseExampleYear01

70

3 years

rr_ExpenseExampleYear03

218

5 years

rr_ExpenseExampleYear05

379

10 years

rr_ExpenseExampleYear10

847

Annual Return 2003

rr_AnnualReturn2003

46.70%

Annual Return 2004

rr_AnnualReturn2004

(8.17%)

Annual Return 2005

rr_AnnualReturn2005

29.17%

Annual Return 2006

rr_AnnualReturn2006

27.03%

Annual Return 2007

rr_AnnualReturn2007

15.12%

Annual Return 2008

rr_AnnualReturn2008

(27.20%)

Annual Return 2009

rr_AnnualReturn2009

43.26%

Annual Return 2010

rr_AnnualReturn2010

44.76%

Annual Return 2011

rr_AnnualReturn2011

(19.29%)

Annual Return 2012

rr_AnnualReturn2012

(7.86%)

1 year

rr_AverageAnnualReturnYear01

(7.86%)

5 years

rr_AverageAnnualReturnYear05

2.34%

10 years

rr_AverageAnnualReturnYear10

11.06%

Inception Date

rr_AverageAnnualReturnInceptionDate

Aug. 17, 1988

GLOBAL GOLD FUND | INVESTOR CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

(8.04%)

5 years

rr_AverageAnnualReturnYear05

1.12%

10 years

rr_AverageAnnualReturnYear10

10.29%

Inception Date

rr_AverageAnnualReturnInceptionDate

Aug. 17, 1988

GLOBAL GOLD FUND | INVESTOR CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

(4.93%)

5 years

rr_AverageAnnualReturnYear05

1.74%

10 years

rr_AverageAnnualReturnYear10

9.71%

Inception Date

rr_AverageAnnualReturnInceptionDate

Aug. 17, 1988

GLOBAL GOLD FUND | A CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

^[1]

Redemption/Exchange Fee (as a percentage of amount redeemed/exchanged for shares held less than 60 days)

rr_RedemptionFeeOverRedemption

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.93%

1 year

rr_ExpenseExampleYear01

665

3 years

rr_ExpenseExampleYear03

855

5 years

rr_ExpenseExampleYear05

1,061

10 years

rr_ExpenseExampleYear10

1,652

1 year

rr_AverageAnnualReturnYear01

(13.34%)

^[2]

5 years

rr_AverageAnnualReturnYear05

0.89%

^[2]

10 years

rr_AverageAnnualReturnYear10

10.13%

^[2]

Inception Date

rr_AverageAnnualReturnInceptionDate

May 06, 1998

^[2]

GLOBAL GOLD FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Redemption/Exchange Fee (as a percentage of amount redeemed/exchanged for shares held less than 60 days)

rr_RedemptionFeeOverRedemption

(1.00%)

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.47%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.48%

1 year

rr_ExpenseExampleYear01

49

3 years

rr_ExpenseExampleYear03

154

5 years

rr_ExpenseExampleYear05

269

10 years

rr_ExpenseExampleYear10

604

1 year

rr_AverageAnnualReturnYear01

(7.66%)

5 years

rr_AverageAnnualReturnYear05

2.56%

Since Inception

rr_AverageAnnualReturnSinceInception

3.12%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 28, 2007

GLOBAL GOLD FUND | C CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

Redemption/Exchange Fee (as a percentage of amount redeemed/exchanged for shares held less than 60 days)

rr_RedemptionFeeOverRedemption

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.68%

1 year

rr_ExpenseExampleYear01

171

3 years

rr_ExpenseExampleYear03

530

5 years

rr_ExpenseExampleYear05

913

10 years

rr_ExpenseExampleYear10

1,985

1 year

rr_AverageAnnualReturnYear01

(8.80%)

5 years

rr_AverageAnnualReturnYear05

1.32%

Since Inception

rr_AverageAnnualReturnSinceInception

1.89%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 28, 2007

GLOBAL GOLD FUND | R CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Redemption/Exchange Fee (as a percentage of amount redeemed/exchanged for shares held less than 60 days)

rr_RedemptionFeeOverRedemption

(1.00%)

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.18%

1 year

rr_ExpenseExampleYear01

121

3 years

rr_ExpenseExampleYear03

375

5 years

rr_ExpenseExampleYear05

650

10 years

rr_ExpenseExampleYear10

1,431

1 year

rr_AverageAnnualReturnYear01

(8.30%)

5 years

rr_AverageAnnualReturnYear05

1.83%

Since Inception

rr_AverageAnnualReturnSinceInception

2.40%

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 28, 2007

INTERNATIONAL CORE EQUITY FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

INTERNATIONAL CORE EQUITY 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

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the 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 101% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

101.00%

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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

50,000

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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 (unless otherwise indicated), that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

In selecting stocks for the fund, the portfolio managers select from publicly traded companies that are primarily located in developed countries, excluding the United States and Canada, that have characteristics similar to those of the companies that comprise the MSCI EAFE^® (Europe, Australasia, Far East) Index. The managers use quantitative models in a two-step process to construct the portfolio of stocks for the fund. First, the portfolio managers rank stocks from most attractive to least attractive by using a quantitative model that combines measures that the portfolio managers believe are predictive of an individual stock performance, such as value, quality and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

The portfolio managers also intend to spread the fund’s holdings across different countries and geographic regions in an effort to manage the risks of an international portfolio. Though the fund invests primarily in securities issued by companies located in developed countries, it may also invest in emerging markets.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Under normal market conditions, at least 80% of the fund's net assets will be invested in equity securities.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Foreign Securities Risk - The fund invests primarily in foreign securities, which are generally riskier than U.S. securities. As a result, the fund is subject to foreign risk, meaning that political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), and natural disasters occurring in a country where the fund invests could cause the fund’s investments in that country to experience gains or losses. Because of these risks, and others, securities of foreign issuers may be less liquid, more volatile, and harder to value than U.S. securities.

• Emerging Markets Risk - Investing in securities of companies located in emerging market countries generally is riskier than investing in securities of companies located in foreign developed countries.

• Currency Risk - Because the fund generally invests in securities denominated in foreign currencies, the fund is subject to currency risk, meaning that the fund could experience gains or losses based solely on changes in the exchange rate between foreign currencies and the U.S. dollar.

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Benchmark Correlation - The fund’s performance will likely be similar to the performance of its benchmark, the MSCI EAFE^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Small and Mid Cap Stocks - The fund may invest in mid-sized and smaller companies, which may be more volatile and subject to greater risk than larger companies. Smaller companies may have limited financial resources, product lines and markets, and their securities may trade less frequently and in more limited volumes than the securities of larger companies, which could lead to higher transaction costs.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Bar Chart and Performance Table [Heading]

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Fund Performance

Performance Narrative [Text Block]

rr_PerformanceNarrativeTextBlock

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Bar Chart Closing [Text Block]

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Highest Performance Quarter (2Q 2009): 21.59%

Lowest Performance Quarter (3Q 2008): -22.12%

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was 18.50%.

Year to Date Return, Label

rr_YearToDateReturnLabel

Investor Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

18.50%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

21.59%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(22.12%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table One Class of after Tax Shown [Text]

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The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary.

Performance Table Closing [Text Block]

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The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

INTERNATIONAL CORE EQUITY FUND | MSCI EAFE® Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

17.32%

5 years

rr_AverageAnnualReturnYear05

(3.69%)

Since Inception

rr_AverageAnnualReturnSinceInception

(0.84%)

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 30, 2006

INTERNATIONAL CORE EQUITY FUND | INVESTOR CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Redemption/Exchange Fee (as a percentage of amount redeemed/exchanged for shares held less than 60 days)

rr_RedemptionFeeOverRedemption

(2.00%)

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

25

Management Fee

rr_ManagementFeesOverAssets

1.15%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.16%

1 year

rr_ExpenseExampleYear01

118

3 years

rr_ExpenseExampleYear03

369

5 years

rr_ExpenseExampleYear05

639

10 years

rr_ExpenseExampleYear10

1,409

Annual Return 2007

rr_AnnualReturn2007

8.41%

Annual Return 2008

rr_AnnualReturn2008

(43.23%)

Annual Return 2009

rr_AnnualReturn2009

21.46%

Annual Return 2010

rr_AnnualReturn2010

10.11%

Annual Return 2011

rr_AnnualReturn2011

(11.57%)

Annual Return 2012

rr_AnnualReturn2012

17.98%

1 year

rr_AverageAnnualReturnYear01

17.98%

5 years

rr_AverageAnnualReturnYear05

(4.55%)

Since Inception

rr_AverageAnnualReturnSinceInception

(1.70%)

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 30, 2006

INTERNATIONAL CORE EQUITY FUND | INVESTOR CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

17.74%

5 years

rr_AverageAnnualReturnYear05

(4.70%)

Since Inception

rr_AverageAnnualReturnSinceInception

(2.16%)

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 30, 2006

INTERNATIONAL CORE EQUITY FUND | INVESTOR CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

12.77%

5 years

rr_AverageAnnualReturnYear05

(3.64%)

Since Inception

rr_AverageAnnualReturnSinceInception

(1.43%)

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 30, 2006

INTERNATIONAL CORE EQUITY FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Redemption/Exchange Fee (as a percentage of amount redeemed/exchanged for shares held less than 60 days)

rr_RedemptionFeeOverRedemption

(2.00%)

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.95%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.96%

1 year

rr_ExpenseExampleYear01

98

3 years

rr_ExpenseExampleYear03

306

5 years

rr_ExpenseExampleYear05

532

10 years

rr_ExpenseExampleYear10

1,178

1 year

rr_AverageAnnualReturnYear01

18.37%

5 years

rr_AverageAnnualReturnYear05

(4.33%)

Since Inception

rr_AverageAnnualReturnSinceInception

(1.49%)

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 30, 2006

INTERNATIONAL CORE EQUITY FUND | A CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

^[1]

Redemption/Exchange Fee (as a percentage of amount redeemed/exchanged for shares held less than 60 days)

rr_RedemptionFeeOverRedemption

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.15%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.41%

1 year

rr_ExpenseExampleYear01

711

3 years

rr_ExpenseExampleYear03

996

5 years

rr_ExpenseExampleYear05

1,302

10 years

rr_ExpenseExampleYear10

2,168

1 year

rr_AverageAnnualReturnYear01

10.98%

5 years

rr_AverageAnnualReturnYear05

(5.91%)

Since Inception

rr_AverageAnnualReturnSinceInception

(2.89%)

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 30, 2006

INTERNATIONAL CORE EQUITY FUND | C CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

Redemption/Exchange Fee (as a percentage of amount redeemed/exchanged for shares held less than 60 days)

rr_RedemptionFeeOverRedemption

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.15%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.16%

1 year

rr_ExpenseExampleYear01

220

3 years

rr_ExpenseExampleYear03

677

5 years

rr_ExpenseExampleYear05

1,160

10 years

rr_ExpenseExampleYear10

2,489

1 year

rr_AverageAnnualReturnYear01

16.88%

5 years

rr_AverageAnnualReturnYear05

(5.49%)

Since Inception

rr_AverageAnnualReturnSinceInception

(2.67%)

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 30, 2006

INTERNATIONAL CORE EQUITY FUND | R CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Redemption/Exchange Fee (as a percentage of amount redeemed/exchanged for shares held less than 60 days)

rr_RedemptionFeeOverRedemption

(2.00%)

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.15%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.66%

1 year

rr_ExpenseExampleYear01

169

3 years

rr_ExpenseExampleYear03

524

5 years

rr_ExpenseExampleYear05

903

10 years

rr_ExpenseExampleYear10

1,964

1 year

rr_AverageAnnualReturnYear01

17.61%

5 years

rr_AverageAnnualReturnYear05

(5.02%)

Since Inception

rr_AverageAnnualReturnSinceInception

(2.17%)

Inception Date

rr_AverageAnnualReturnInceptionDate

Nov. 30, 2006

INCOME & GROWTH FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

INCOME & GROWTH FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

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The fund seeks long-term capital growth by investing in common stocks.

Objective, Secondary [Text Block]

rr_ObjectiveSecondaryTextBlock

Income is a secondary objective.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the 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 74% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

74.00%

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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

50,000

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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, that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

In selecting stocks for the fund, the portfolio managers use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum (with a tilt towards value). Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return. The portfolio managers also attempt to create a dividend yield that will be greater than the S&P 500^® Index.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the S&P 500^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Low Dividend Yield - Although current income is an objective of the fund, if the stocks that make up the S&P 500^® Index do not have a high dividend yield, then the fund’s dividend yield will not be high.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) 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 risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Performance Quarter (2Q 2003): 16.41% 

Lowest Performance Quarter (4Q 2008): -19.93% 

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was 22.04%. 

Year to Date Return, Label

rr_YearToDateReturnLabel

Investor Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

22.04%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2003

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

16.41%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(19.93%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

INCOME & GROWTH FUND | S&P 500® Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

16.00%

5 years

rr_AverageAnnualReturnYear05

1.66%

10 years

rr_AverageAnnualReturnYear10

7.10%

INCOME & GROWTH FUND | INVESTOR CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

25

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.68%

1 year

rr_ExpenseExampleYear01

70

3 years

rr_ExpenseExampleYear03

218

5 years

rr_ExpenseExampleYear05

379

10 years

rr_ExpenseExampleYear10

847

Annual Return 2003

rr_AnnualReturn2003

29.62%

Annual Return 2004

rr_AnnualReturn2004

12.98%

Annual Return 2005

rr_AnnualReturn2005

4.79%

Annual Return 2006

rr_AnnualReturn2006

17.17%

Annual Return 2007

rr_AnnualReturn2007

(0.29%)

Annual Return 2008

rr_AnnualReturn2008

(34.68%)

Annual Return 2009

rr_AnnualReturn2009

17.92%

Annual Return 2010

rr_AnnualReturn2010

14.10%

Annual Return 2011

rr_AnnualReturn2011

3.02%

Annual Return 2012

rr_AnnualReturn2012

14.52%

1 year

rr_AverageAnnualReturnYear01

14.52%

5 years

rr_AverageAnnualReturnYear05

0.73%

10 years

rr_AverageAnnualReturnYear10

6.39%

Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 17, 1990

INCOME & GROWTH FUND | INVESTOR CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

14.16%

5 years

rr_AverageAnnualReturnYear05

0.45%

10 years

rr_AverageAnnualReturnYear10

5.70%

Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 17, 1990

INCOME & GROWTH FUND | INVESTOR CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

9.90%

5 years

rr_AverageAnnualReturnYear05

0.57%

10 years

rr_AverageAnnualReturnYear10

5.48%

Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 17, 1990

INCOME & GROWTH FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.47%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.48%

1 year

rr_ExpenseExampleYear01

49

3 years

rr_ExpenseExampleYear03

154

5 years

rr_ExpenseExampleYear05

269

10 years

rr_ExpenseExampleYear10

604

1 year

rr_AverageAnnualReturnYear01

14.78%

5 years

rr_AverageAnnualReturnYear05

0.93%

10 years

rr_AverageAnnualReturnYear10

6.60%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jan. 28, 1998

INCOME & GROWTH FUND | A CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

^[1]

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.93%

1 year

rr_ExpenseExampleYear01

665

3 years

rr_ExpenseExampleYear03

855

5 years

rr_ExpenseExampleYear05

1,061

10 years

rr_ExpenseExampleYear10

1,652

1 year

rr_AverageAnnualReturnYear01

7.74%

^[2]

5 years

rr_AverageAnnualReturnYear05

(0.70%)

^[2]

10 years

rr_AverageAnnualReturnYear10

5.51%

^[2]

Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 15, 1997

^[2]

INCOME & GROWTH FUND | C CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.68%

1 year

rr_ExpenseExampleYear01

171

3 years

rr_ExpenseExampleYear03

530

5 years

rr_ExpenseExampleYear05

913

10 years

rr_ExpenseExampleYear10

1,985

1 year

rr_AverageAnnualReturnYear01

13.43%

5 years

rr_AverageAnnualReturnYear05

(0.26%)

10 years

rr_AverageAnnualReturnYear10

5.36%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jun. 28, 2001

INCOME & GROWTH FUND | R CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.18%

1 year

rr_ExpenseExampleYear01

121

3 years

rr_ExpenseExampleYear03

375

5 years

rr_ExpenseExampleYear05

650

10 years

rr_ExpenseExampleYear10

1,431

1 year

rr_AverageAnnualReturnYear01

13.96%

5 years

rr_AverageAnnualReturnYear05

0.23%

Since Inception

rr_AverageAnnualReturnSinceInception

4.76%

Inception Date

rr_AverageAnnualReturnInceptionDate

Aug. 29, 2003

NT CORE EQUITY PLUS FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

NT CORE EQUITY PLUS 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

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses you may pay if you buy and hold shares of the fund.

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 111% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

111.00%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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, that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investments Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The managers use quantitative models to construct the portfolio of equity securities for the fund. The fund invests approximately 130% of its assets in long positions, while 30% of its assets are sold short. A long position arises when the fund buys a security outright. A short position arises when the fund sells a security it does not own but has borrowed in anticipation that the market price of the security will decline. If the market price in fact declines, the fund can replace the borrowed security at a lower price and capture the value represented by the difference between the higher sale price and the lower replacement price. The proceeds from the securities sold short are used to purchase an additional 30% of long positions. The net investment exposure for the fund is a 100% long market exposure.

The portfolio managers buy, or take long positions in, equity securities that they have identified as the most attractive and take short positions in equity securities that they have identified as the least attractive using a multi-factor quantitative model in a two-step process. In the first step, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from the most attractive to least attractive based on an objective set of measures, including a stock’s value, quality, growth, and momentum. In the second step, the managers use a quantitative model to build a portfolio that provides the optimal balance between risk and expected return.

The portfolio managers generally sell a stock from the fund's long portfolio when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

The fund’s use of short selling as a primary investment strategy creates leverage in an attempt to increase returns.

The fund is not permitted to invest in securities issued by companies assigned the Global Industry Classification Standard (GICS) for the tobacco industry.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Short Sales Risk - If the market price of a security increases after the fund borrows the security, the fund may suffer a loss when it replaces the borrowed security at the higher price. Any loss will be increased by the amount of compensation, interest or dividends, and transaction costs the fund must pay to the lender of the borrowed security.

• Leverage Risk - The fund’s investment strategy utilizes leverage, which can increase market exposure and subject the fund to greater risk and higher volatility.

• Overweighting Risk - If the fund is overweighted in a stock or sector, any negative development related to that stock or sector will have a greater impact on the fund than other funds that are not overweighted in that stock or sector.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the S&P 500^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Tobacco Exclusion - The fund’s prohibition on tobacco-related investments may cause it to forego profitable investment opportunities.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) 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 risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Performance Quarter (1Q 2012): 13.33%

Lowest Performance Quarter (2Q 2012): -3.86% 

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was 21.98%.

Year to Date Return, Label

rr_YearToDateReturnLabel

Investor Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

21.98%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Mar. 31, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

13.33%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Jun. 30, 2012

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(3.86%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

NT CORE EQUITY PLUS FUND | S&P 500® Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

16.00%

Since Inception

rr_AverageAnnualReturnSinceInception

15.96%

Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 01, 2011

NT CORE EQUITY PLUS FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

Management Fee

rr_ManagementFeesOverAssets

1.10%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Dividends on Short Sales

rr_Component1OtherExpensesOverAssets

0.31%

Broker Fees and Charges on Short Sales

rr_Component2OtherExpensesOverAssets

0.25%

Other

rr_Component3OtherExpensesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.56%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.66%

1 year

rr_ExpenseExampleYear01

169

3 years

rr_ExpenseExampleYear03

524

5 years

rr_ExpenseExampleYear05

903

10 years

rr_ExpenseExampleYear10

1,964

Annual Return 2012

rr_AnnualReturn2012

16.49%

1 year

rr_AverageAnnualReturnYear01

16.49%

Since Inception

rr_AverageAnnualReturnSinceInception

15.68%

Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 01, 2011

NT CORE EQUITY PLUS FUND | INSTITUTIONAL CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

16.05%

Since Inception

rr_AverageAnnualReturnSinceInception

15.27%

Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 01, 2011

NT CORE EQUITY PLUS FUND | INSTITUTIONAL CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

11.18%

Since Inception

rr_AverageAnnualReturnSinceInception

13.29%

Inception Date

rr_AverageAnnualReturnInceptionDate

Dec. 01, 2011

NT EQUITY GROWTH FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

NT EQUITY 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

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses you may pay if you buy and hold shares of the fund.

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 95% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

95.00%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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, that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

In selecting stocks for the fund, the portfolio managers use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

Under normal market conditions, at least 80% of the fund’s net assets will be invested in equity securities.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

The fund is not permitted to invest in securities issued by companies assigned the Global Industry Classification Standard (GICS) for the tobacco industry.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the S&P 500^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Tobacco Exclusion - The fund’s prohibition on tobacco-related investments may cause it to forego profitable investment opportunities.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) 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 risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Institutional Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Institutional Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Performance Quarter (3Q 2009): 14.93%

Lowest Performance Quarter (4Q 2008): -21.29%

As of September 30, 2013, the most recent calendar quarter end, the fund’s Institutional Class year-to-date return was 19.97%.

Year to Date Return, Label

rr_YearToDateReturnLabel

Institutional Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

19.97%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

14.93%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(21.29%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

NT EQUITY GROWTH FUND | S&P 500® Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

16.00%

5 years

rr_AverageAnnualReturnYear05

1.66%

Since Inception

rr_AverageAnnualReturnSinceInception

3.71%

Inception Date

rr_AverageAnnualReturnInceptionDate

May 12, 2006

NT EQUITY GROWTH FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

Management Fee

rr_ManagementFeesOverAssets

0.47%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.48%

1 year

rr_ExpenseExampleYear01

49

3 years

rr_ExpenseExampleYear03

154

5 years

rr_ExpenseExampleYear05

269

10 years

rr_ExpenseExampleYear10

604

Annual Return 2007

rr_AnnualReturn2007

3.57%

Annual Return 2008

rr_AnnualReturn2008

(34.17%)

Annual Return 2009

rr_AnnualReturn2009

20.34%

Annual Return 2010

rr_AnnualReturn2010

14.75%

Annual Return 2011

rr_AnnualReturn2011

4.06%

Annual Return 2012

rr_AnnualReturn2012

16.28%

1 year

rr_AverageAnnualReturnYear01

16.28%

5 years

rr_AverageAnnualReturnYear05

1.92%

Since Inception

rr_AverageAnnualReturnSinceInception

3.38%

Inception Date

rr_AverageAnnualReturnInceptionDate

May 12, 2006

NT EQUITY GROWTH FUND | INSTITUTIONAL CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

15.13%

5 years

rr_AverageAnnualReturnYear05

1.41%

Since Inception

rr_AverageAnnualReturnSinceInception

2.92%

Inception Date

rr_AverageAnnualReturnInceptionDate

May 12, 2006

NT EQUITY GROWTH FUND | INSTITUTIONAL CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

12.10%

5 years

rr_AverageAnnualReturnYear05

1.59%

Since Inception

rr_AverageAnnualReturnSinceInception

2.85%

Inception Date

rr_AverageAnnualReturnInceptionDate

May 12, 2006

NT SMALL COMPANY FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

NT SMALL COMPANY 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

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses you may pay if you buy and hold shares of the fund.

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 106% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

106.00%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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, that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

Under normal market conditions, the fund will invest at least 80% of its net assets in stocks of smaller-capitalization U.S. companies. The managers consider small companies to be those that, at the time of investment, have a market capitalization not greater than that of the largest company in the Russell 2000^® Index. The portfolio managers use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily smaller U.S. companies, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

The fund is not permitted to invest in securities issued by companies assigned the Global Industry Classification Standard (GICS) for the tobacco industry.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Small Cap Stocks - The smaller companies in which the fund invests may be more volatile and subject to greater risk than larger companies. Smaller companies may have limited financial resources, product lines and markets, and their securities may trade less frequently and in more limited volumes than the securities of larger companies, which could lead to higher transaction costs.

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the Russell 2000^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.  

• Tobacco Exclusion - The fund’s prohibition on tobacco-related investments may cause it to forego profitable investment opportunities.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) 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 risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Institutional Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Institutional Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Performance Quarter (3Q 2009): 17.06%

Lowest Performance Quarter (4Q 2008): -26.99% 

As of September 30, 2013, the most recent calendar quarter end, the fund's Institutional Class year-to-date return was 30.11%.

Year to Date Return, Label

rr_YearToDateReturnLabel

Institutional Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

30.11%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2009

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.06%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(26.99%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

NT SMALL COMPANY FUND | Russell 2000® Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

16.35%

5 years

rr_AverageAnnualReturnYear05

3.55%

Since Inception

rr_AverageAnnualReturnSinceInception

3.47%

Inception Date

rr_AverageAnnualReturnInceptionDate

May 12, 2006

NT SMALL COMPANY FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.68%

1 year

rr_ExpenseExampleYear01

70

3 years

rr_ExpenseExampleYear03

218

5 years

rr_ExpenseExampleYear05

379

10 years

rr_ExpenseExampleYear10

847

Annual Return 2007

rr_AnnualReturn2007

(5.83%)

Annual Return 2008

rr_AnnualReturn2008

(38.20%)

Annual Return 2009

rr_AnnualReturn2009

20.18%

Annual Return 2010

rr_AnnualReturn2010

27.50%

Annual Return 2011

rr_AnnualReturn2011

(0.81%)

Annual Return 2012

rr_AnnualReturn2012

13.98%

1 year

rr_AverageAnnualReturnYear01

13.98%

5 years

rr_AverageAnnualReturnYear05

1.37%

Since Inception

rr_AverageAnnualReturnSinceInception

(0.15%)

Inception Date

rr_AverageAnnualReturnInceptionDate

May 12, 2006

NT SMALL COMPANY FUND | INSTITUTIONAL CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

12.97%

5 years

rr_AverageAnnualReturnYear05

0.88%

Since Inception

rr_AverageAnnualReturnSinceInception

(0.53%)

Inception Date

rr_AverageAnnualReturnInceptionDate

May 12, 2006

NT SMALL COMPANY FUND | INSTITUTIONAL CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

10.39%

5 years

rr_AverageAnnualReturnYear05

1.12%

Since Inception

rr_AverageAnnualReturnSinceInception

(0.16%)

Inception Date

rr_AverageAnnualReturnInceptionDate

May 12, 2006

STRATEGIC INFLATION OPPORTUNITIES FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

STRATEGIC INFLATION OPPORTUNITIES FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks total real return.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 17 of the fund’s prospectus and Sales Charges in Appendix B of the 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)

Fee Waiver or Reimbursement over Assets, Date of Termination

rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination

10/31/14

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 85% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

85.00%

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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 17 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

50,000

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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, that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

The fund’s asset allocation strategy seeks to diversify its investments among U.S. Treasury inflation-indexed securities, non-U.S. dollar investments, commodity-related investments, companies engaged in the real estate industry (including securities issued by real estate investment trusts (REITs)), and securities that reflect the price of gold bullion, all in an effort to provide investors total real return. Total real return is total return reduced by the expected impact of inflation. The fund’s investment strategy has been designed in an effort to protect the fund’s investors from the effects of rising U.S. inflation. Generally, the portfolio managers intend to diversify the fund’s investments as indicated in the following table. The table indicates the fund’s neutral mix, that is, how the fund’s investments generally will be allocated among its major asset classes over the long term, and the ranges within which the portfolio managers may make tactical allocations as a result of changing economic conditions or the portfolio managers’ inflation expectations. The portfolio managers will regularly review the fund’s asset mix and adjust the allocation among asset classes as necessary to provide the fund what they believe is the most favorable outlook for achieving the fund’s objective. By adjusting the allocation among asset classes the portfolio managers can moderate risks associated with each asset category.

	U.S. Inflation-Indexed and other U.S. Fixed-Income Securities	Non-U.S. Dollar Investments	Commodity-Related Investments	Real Estate-Related Securities	Gold Securities
Neutral Mix	45%	25%	15%	10%	5%
Operating Ranges	25-65%	15-35%	5-25%	0-20%	0-10%

To help protect against U.S. inflation, the fund will invest a portion of its assets in inflation-indexed debt securities. These securities include inflation-indexed U.S. Treasury securities, inflation-indexed securities issued by U.S. government agencies and instrumentalities other than the U.S. Treasury, and inflation-indexed securities issued by other entities such as corporations. Inflation-indexed securities are designed to protect the future purchasing power of the money invested in them.

The portfolio managers may also purchase U.S. Treasury securities, U.S. Treasury futures, and other U.S. fixed-income securities that are not linked to inflation whether issued by the U.S. government, its agencies or instrumentalities, municipalities, corporations or other non-governmental issuers. A portion of these investments may be in high-yield securities. The fund also may invest in derivative instruments such as options, futures contracts, options on futures contracts, and swap agreements (including, but not limited to, credit default swap agreements), or in mortgage- or asset-backed securities, provided that such instruments are in keeping with the fund’s investment objective.

The fund also will invest a portion of its assets in debt securities of foreign issuers, including issuers located in emerging markets. In managing the fund’s non-U.S. dollar investments, the fund will buy and sell foreign currencies regularly, either in the spot (i.e., cash) market or with foreign currency forward contracts.

Foreign currency forward contracts are agreements to exchange a specific amount of one currency for a specified amount of another at a future date. The date may be any agreed fixed number of days in the future. The amount of currency to be exchanged, the price at which the exchange will take place, and the date of the exchange are negotiated when the fund enters into the contract and are fixed for the term of the contract. Forward contracts are traded in an interbank market conducted directly between currency traders (usually large commercial banks) and their customers. A forward contract generally has no deposit requirement and is consummated without payment of any commission. However, the fund may enter into forward contracts with deposit requirements or commissions.

The fund may also invest in high-quality non-dollar-denominated foreign government and foreign corporate debt securities, as well as inflation-indexed securities issued by foreign governments and corporations. When the managers believe it is prudent, the fund may also invest a portion of the assets from this portion in equity securities of foreign companies, including issuers located in emerging markets. Within this non-U.S. dollar portion, the fund may also invest in short-term securities, including money markets, securities issued or guaranteed by the U.S. government and its agencies and instrumentalities, and commercial paper and other U.S. dollar debt investments.

The fund also will invest a portion of its assets in commodity-related investments. Commodities are assets that have tangible properties, such as oil, metals and agricultural products. Under normal market conditions, the fund’s commodity-related investments will be allocated between equity securities of U.S. and foreign companies engaged in commodity-related businesses and investments that provide investment exposure to underlying investible commodities. Investments in equity securities of foreign companies engaged in commodity-related businesses do not apply to the fund’s neutral mix or operating range for non-U.S. dollar investments. To achieve exposure to underlying commodities, the fund may invest in commodity-linked notes, commodity-related exchange traded notes (ETNs), and exchange traded funds (ETFs) or other pooled investment funds that invest in underlying commodities or that seek to track the performance of a commodity or resource index.

The fund will also invest a portion of its assets in real estate investment trusts (REITs), REIT ETFs and equity securities issued by companies engaged in the real estate industry. A company is considered a real estate company if, in the opinion of the portfolio managers, at least 50% of its revenues or 50% of the market value of its assets at the time the securities are purchased by the fund are attributed to the ownership, construction, management or sale of real estate.

The fund will also invest a portion of its assets in securities that reflect the performance of the price of gold bullion, including through exchange traded funds (ETFs) or other pooled investment funds that invest in underlying gold.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Style Risk - If at any time the market is not favoring the fund’s investment style, which is designed for high and rising inflationary cycles, the fund’s gains may not be as big as, or its losses may be bigger than, those of other funds using different investment styles.

• Nondiversification - The fund is classified as nondiversified. A nondiversified fund may invest a greater percentage of its assets in a smaller number of securities than a diversified fund. This gives the managers the flexibility to hold large positions in a small number of securities. If so, a price change in any one of those securities may have a greater impact on the fund’s share price than would be the case for a diversified fund.

• Real Interest Rate Risk - Inflation-indexed securities trade at prevailing real, or after-inflation, interest rates. Changes in real interest rates affect the value of such securities. Generally, when real interest rates rise, the value of the fund’s fixed-income securities will decline. The opposite is true when real interest rates decline.

• Credit Risk - The value of the fund’s fixed-income securities will be affected adversely by any erosion, or perceived erosion, in the ability of the issuers of these securities to make interest and principal payments as they become due.

• Foreign Securities Risk - The fund invests in foreign securities, which are generally riskier than U.S. securities. As a result, the fund is subject to foreign risk, meaning that political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), and natural disasters occurring in a country where the fund invests could cause the fund’s investments in that country to experience gains or losses. Because of these risks, and others, securities of foreign issuers may be less liquid, more volatile, and harder to value than U.S. securities.

• Currency Risk - The fund is subject to the risk of a decline in the value of a foreign currency versus the U.S. dollar, which reduces the dollar value of securities denominated in that currency. The overall impact on the fund’s holdings may be significant depending on the currencies represented in the portfolio, how each one appreciates or depreciates in relation to the U.S. dollar, and whether currency positions are hedged. Currency trends can be volatile, and to the extent the fund purchases and sells currencies, it will also be subject to the risk that its trading strategies, including efforts at hedging, will not succeed.

• Commodity and Gold Investing Risk - The fund’s commodity- and gold-related investments may be subject to greater volatility than investments in traditional securities. The value of the fund’s commodity- and gold-related investments may be affected by changes in overall market movements, interest rate changes, and volatility in commodity- and gold-related indexes. The value of these investments may also be affected by factors affecting a particular commodity, such as weather, disease, embargoes, tariffs, taxes and economic, political and regulatory developments.

• Real Estate Investing - An investment in the fund may be subject to many of the same risks as a direct investment in real estate. These risks include changes in economic conditions, interest rates, property values, property tax increases, overbuilding and increased competition, environmental contamination, zoning and natural disasters. This is due to the fact that the value of the fund’s investments may be affected by the value of the real estate owned by the companies in which it invests.

• Emerging Market Risk - Investing in securities of companies located in emerging market countries generally is also riskier than investing in securities of companies located in foreign developed countries. Emerging market countries may have unstable governments and/or economies that are subject to sudden change. These changes may be magnified by the countries’ emergent financial markets, resulting in significant volatility to investments in these countries.

• Derivative Risk - The use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional instruments. Derivatives are subject to a number of risks, including liquidity, interest rate, market, credit and correlation risk.

• Liquidity Risk - The fund may also be subject to liquidity risk. During periods of market turbulence or unusually low trading activity, in order to meet redemptions it may be necessary for the fund to sell securities at prices that could have an adverse effect on the fund’s share price.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Nondiversified Status [Text]

rr_RiskNondiversifiedStatus

Nondiversification - The fund is classified as nondiversified. A nondiversified fund may invest a greater percentage of its assets in a smaller number of securities than a diversified fund. This gives the managers the flexibility to hold large positions in a small number of securities. If so, a price change in any one of those securities may have a greater impact on the fund’s share price than would be the case for a diversified fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) 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 risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, including yields, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Performance Quarter (3Q 2012): 4.40%

Lowest Performance Quarter(3Q 2011): -7.83%

As of September 30, 2013, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was -2.67%.

Year to Date Return, Label

rr_YearToDateReturnLabel

Investor Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

(2.67%)

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Sep. 30, 2012

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

4.40%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2011

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(7.83%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

STRATEGIC INFLATION OPPORTUNITIES FUND | Barclays U.S. 1-3 Month Treasury Bill Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

0.08%

Since Inception

rr_AverageAnnualReturnSinceInception

0.09%

Inception Date

rr_AverageAnnualReturnInceptionDate

Apr. 30, 2010

STRATEGIC INFLATION OPPORTUNITIES FUND | INVESTOR CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

25

Management Fee

rr_ManagementFeesOverAssets

1.08%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.11%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.20%

Fee Waiver or Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.20%

^[6]

Total Annual Fund Operating Expenses After Waiver

rr_NetExpensesOverAssets

1.00%

1 year

rr_ExpenseExampleYear01

102

3 years

rr_ExpenseExampleYear03

362

5 years

rr_ExpenseExampleYear05

641

10 years

rr_ExpenseExampleYear10

1,436

Annual Return 2011

rr_AnnualReturn2011

(2.20%)

Annual Return 2012

rr_AnnualReturn2012

3.59%

1 year

rr_AverageAnnualReturnYear01

3.59%

Since Inception

rr_AverageAnnualReturnSinceInception

2.35%

Inception Date

rr_AverageAnnualReturnInceptionDate

Apr. 30, 2010

STRATEGIC INFLATION OPPORTUNITIES FUND | INVESTOR CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

3.59%

Since Inception

rr_AverageAnnualReturnSinceInception

2.04%

Inception Date

rr_AverageAnnualReturnInceptionDate

Apr. 30, 2010

STRATEGIC INFLATION OPPORTUNITIES FUND | INVESTOR CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

2.34%

Since Inception

rr_AverageAnnualReturnSinceInception

1.83%

Inception Date

rr_AverageAnnualReturnInceptionDate

Apr. 30, 2010

STRATEGIC INFLATION OPPORTUNITIES FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.88%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.11%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.00%

Fee Waiver or Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.20%

^[6]

Total Annual Fund Operating Expenses After Waiver

rr_NetExpensesOverAssets

0.80%

1 year

rr_ExpenseExampleYear01

82

3 years

rr_ExpenseExampleYear03

299

5 years

rr_ExpenseExampleYear05

534

10 years

rr_ExpenseExampleYear10

1,207

1 year

rr_AverageAnnualReturnYear01

3.85%

Since Inception

rr_AverageAnnualReturnSinceInception

2.55%

Inception Date

rr_AverageAnnualReturnInceptionDate

Apr. 30, 2010

STRATEGIC INFLATION OPPORTUNITIES FUND | A CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

^[1]

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.08%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.11%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.45%

Fee Waiver or Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.20%

^[6]

Total Annual Fund Operating Expenses After Waiver

rr_NetExpensesOverAssets

1.25%

1 year

rr_ExpenseExampleYear01

695

3 years

rr_ExpenseExampleYear03

989

5 years

rr_ExpenseExampleYear05

1,304

10 years

rr_ExpenseExampleYear10

2,193

1 year

rr_AverageAnnualReturnYear01

(2.54%)

Since Inception

rr_AverageAnnualReturnSinceInception

(0.13%)

Inception Date

rr_AverageAnnualReturnInceptionDate

Apr. 30, 2010

STRATEGIC INFLATION OPPORTUNITIES FUND | C CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.08%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.11%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

2.20%

Fee Waiver or Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.20%

^[6]

Total Annual Fund Operating Expenses After Waiver

rr_NetExpensesOverAssets

2.00%

1 year

rr_ExpenseExampleYear01

203

3 years

rr_ExpenseExampleYear03

670

5 years

rr_ExpenseExampleYear05

1,162

10 years

rr_ExpenseExampleYear10

2,515

1 year

rr_AverageAnnualReturnYear01

2.50%

Since Inception

rr_AverageAnnualReturnSinceInception

1.30%

Inception Date

rr_AverageAnnualReturnInceptionDate

Apr. 30, 2010

STRATEGIC INFLATION OPPORTUNITIES FUND | R CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

1.08%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Acquired Fund Fees and Expenses

rr_AcquiredFundFeesAndExpensesOverAssets

0.11%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.70%

Fee Waiver or Reimbursement

rr_FeeWaiverOrReimbursementOverAssets

0.20%

^[6]

Total Annual Fund Operating Expenses After Waiver

rr_NetExpensesOverAssets

1.50%

1 year

rr_ExpenseExampleYear01

153

3 years

rr_ExpenseExampleYear03

517

5 years

rr_ExpenseExampleYear05

905

10 years

rr_ExpenseExampleYear10

1,990

1 year

rr_AverageAnnualReturnYear01

3.10%

Since Inception

rr_AverageAnnualReturnSinceInception

1.82%

Inception Date

rr_AverageAnnualReturnInceptionDate

Apr. 30, 2010

SMALL COMPANY FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

SMALL COMPANY FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks long-term capital growth by investing primarily in stocks of small companies.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the 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 93% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

93.00%

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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Expense Breakpoint, Minimum Investment Required [Amount]

rr_ExpenseBreakpointMinimumInvestmentRequiredAmount

50,000

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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, that you earn 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:

Strategy [Heading]

rr_StrategyHeading

Principal Investment Strategies

Strategy Narrative [Text Block]

rr_StrategyNarrativeTextBlock

Under normal market conditions, the fund will invest at least 80% of its net assets in stocks of smaller-capitalization U.S. companies. The portfolio managers consider small companies to be those that, at the time of investment, have a market capitalization not greater than that of the largest company in the Russell 2000^® Index. The portfolio managers use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily smaller U.S. companies, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Small Cap Stocks - The smaller companies in which the fund invests may be more volatile and subject to greater risk than larger companies. Smaller companies may have limited financial resources, product lines and markets, and their securities may trade less frequently and in more limited volumes than the securities of larger companies, which could lead to higher transaction costs.

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the Russell 2000^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) 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 risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Performance Quarter (2Q 2003): 22.31%

Lowest Performance Quarter (4Q 2008): -26.86%

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was 29.93%.

Year to Date Return, Label

rr_YearToDateReturnLabel

Investor Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

29.93%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2003

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

22.31%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Dec. 31, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(26.86%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table One Class of after Tax Shown [Text]

rr_PerformanceTableOneClassOfAfterTaxShown

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

SMALL COMPANY FUND | Russell 2000® Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

16.35%

5 years

rr_AverageAnnualReturnYear05

3.56%

10 years

rr_AverageAnnualReturnYear10

9.72%

SMALL COMPANY FUND | INVESTOR CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

25

Management Fee

rr_ManagementFeesOverAssets

0.87%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.88%

1 year

rr_ExpenseExampleYear01

90

3 years

rr_ExpenseExampleYear03

281

5 years

rr_ExpenseExampleYear05

488

10 years

rr_ExpenseExampleYear10

1,085

Annual Return 2003

rr_AnnualReturn2003

53.57%

Annual Return 2004

rr_AnnualReturn2004

28.28%

Annual Return 2005

rr_AnnualReturn2005

7.13%

Annual Return 2006

rr_AnnualReturn2006

6.15%

Annual Return 2007

rr_AnnualReturn2007

(5.72%)

Annual Return 2008

rr_AnnualReturn2008

(38.14%)

Annual Return 2009

rr_AnnualReturn2009

20.46%

Annual Return 2010

rr_AnnualReturn2010

27.07%

Annual Return 2011

rr_AnnualReturn2011

(0.77%)

Annual Return 2012

rr_AnnualReturn2012

13.92%

1 year

rr_AverageAnnualReturnYear01

13.92%

5 years

rr_AverageAnnualReturnYear05

1.37%

10 years

rr_AverageAnnualReturnYear10

8.49%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 31, 1998

SMALL COMPANY FUND | INVESTOR CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

13.73%

5 years

rr_AverageAnnualReturnYear05

1.31%

10 years

rr_AverageAnnualReturnYear10

7.74%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 31, 1998

SMALL COMPANY FUND | INVESTOR CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

9.30%

5 years

rr_AverageAnnualReturnYear05

1.16%

10 years

rr_AverageAnnualReturnYear10

7.30%

Inception Date

rr_AverageAnnualReturnInceptionDate

Jul. 31, 1998

SMALL COMPANY FUND | INSTITUTIONAL CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.68%

1 year

rr_ExpenseExampleYear01

70

3 years

rr_ExpenseExampleYear03

218

5 years

rr_ExpenseExampleYear05

379

10 years

rr_ExpenseExampleYear10

847

1 year

rr_AverageAnnualReturnYear01

14.00%

5 years

rr_AverageAnnualReturnYear05

1.56%

10 years

rr_AverageAnnualReturnYear10

8.69%

Inception Date

rr_AverageAnnualReturnInceptionDate

Oct. 01, 1999

SMALL COMPANY FUND | A CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

^[1]

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.87%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.25%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.13%

1 year

rr_ExpenseExampleYear01

684

3 years

rr_ExpenseExampleYear03

914

5 years

rr_ExpenseExampleYear05

1,162

10 years

rr_ExpenseExampleYear10

1,870

1 year

rr_AverageAnnualReturnYear01

7.07%

^[7]

5 years

rr_AverageAnnualReturnYear05

(0.08%)

^[7]

10 years

rr_AverageAnnualReturnYear10

7.58%

^[7]

Inception Date

rr_AverageAnnualReturnInceptionDate

Sep. 07, 2000

^[7]

SMALL COMPANY FUND | C CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

1.00%

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.87%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

1.00%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.88%

1 year

rr_ExpenseExampleYear01

191

3 years

rr_ExpenseExampleYear03

592

5 years

rr_ExpenseExampleYear05

1,017

10 years

rr_ExpenseExampleYear10

2,198

1 year

rr_AverageAnnualReturnYear01

12.85%

5 years

rr_AverageAnnualReturnYear05

0.36%

^[8]

10 years

rr_AverageAnnualReturnYear10

7.41%

^[8]

Inception Date

rr_AverageAnnualReturnInceptionDate

Mar. 01, 2010

SMALL COMPANY FUND | R CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

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 lower of the original offering price or redemption proceeds when redeemed within one year of purchase)

rr_MaximumDeferredSalesChargeOverOfferingPrice

none

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

none

Management Fee

rr_ManagementFeesOverAssets

0.87%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

0.50%

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

1.38%

1 year

rr_ExpenseExampleYear01

141

3 years

rr_ExpenseExampleYear03

438

5 years

rr_ExpenseExampleYear05

756

10 years

rr_ExpenseExampleYear10

1,656

1 year

rr_AverageAnnualReturnYear01

13.24%

5 years

rr_AverageAnnualReturnYear05

0.86%

Since Inception

rr_AverageAnnualReturnSinceInception

5.64%

Inception Date

rr_AverageAnnualReturnInceptionDate

Aug. 29, 2003

UTILITIES FUND

Prospectus [Line Items]

rr_ProspectusLineItems

Risk/Return [Heading]

rr_RiskReturnHeading

UTILITIES FUND

Objective [Heading]

rr_ObjectiveHeading

Investment Objective

Objective, Primary [Text Block]

rr_ObjectivePrimaryTextBlock

The fund seeks current income and long-term growth of capital and income. The fund invests at least 80% of its assets in equity securities of companies engaged in the utilities industry.

Expense [Heading]

rr_ExpenseHeading

Fees and Expenses

Expense Narrative [Text Block]

rr_ExpenseNarrativeTextBlock

The following table describes the fees and expenses 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)

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 41% of the average value of its portfolio.

Portfolio Turnover, Rate

rr_PortfolioTurnoverRate

41.00%

Expense Example [Heading]

rr_ExpenseExampleHeading

Example

Expense Example Narrative [Text Block]

rr_ExpenseExampleNarrativeTextBlock

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

Expense Example by, Year, Caption [Text]

rr_ExpenseExampleByYearCaption

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, that you earn 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:

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 in equity securities of companies engaged in the utilities industry. The managers consider a company to be engaged in the utilities industry if

• the company’s securities are listed in at least one index that is made up exclusively of companies engaged in one or more of the following industries: electricity, natural gas, telecommunications services, cable television, water or sanitation services; or

• the company derives 50% or more of its revenues or net profits from the ownership or operation of facilities used to provide electricity, natural gas, telecommunications services, cable television, water or sanitation services.

The portfolio managers use quantitative and qualitative management techniques as well as risk controls to construct the fund’s portfolio. The quantitative process involves ranking stocks based on their growth and valuation characteristics. This ranking may be modified by the portfolio managers after they evaluate qualitative factors such as regulatory environment, industry conditions and company specific events. Finally, the managers use a quantitative model to build a portfolio of stocks that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Strategy Portfolio Concentration [Text]

rr_StrategyPortfolioConcentration

Under normal market conditions, the fund invests at least 80% of its net assets in equity securities of companies engaged in the utilities industry. The fund concentrates its investments in the utilities industry, which at times may be limited to a relatively small number of securities. Therefore, the fund may be subject to greater risks and market fluctuations than a portfolio representing a broader range of industries. The performance of the utilities industry will depend in part on investor perception of the sector relative to other sectors. Companies in the utilities industry are subject to various industry-specific risks.

Risk [Heading]

rr_RiskHeading

Principal Risks

Risk Narrative [Text Block]

rr_RiskNarrativeTextBlock

• Concentration Risk - The fund concentrates its investments in the utilities industry, which at times may be limited to a relatively small number of securities. Therefore, the fund may be subject to greater risks and market fluctuations than a portfolio representing a broader range of industries. The performance of the utilities industry will depend in part on investor perception of the sector relative to other sectors. Companies in the utilities industry are subject to various industry-specific risks.

• Foreign Securities Risk - The fund may invest in foreign securities, which may be riskier than investing in U.S. securities. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Risk Lose Money [Text]

rr_RiskLoseMoney

Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

Risk Not Insured Depository Institution [Text]

rr_RiskNotInsuredDepositoryInstitution

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) 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 risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Performance Information Illustrates Variability of Returns [Text]

rr_PerformanceInformationIllustratesVariabilityOfReturns

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance.

Performance Availability Website Address [Text]

rr_PerformanceAvailabilityWebSiteAddress

americancentury.com

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

Calendar Year Total Returns

Bar Chart Does Not Reflect Sales Loads [Text]

rr_BarChartDoesNotReflectSalesLoads

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Bar Chart Closing [Text Block]

rr_BarChartClosingTextBlock

Highest Performance Quarter (2Q 2003): 17.77%

Lowest Performance Quarter (3Q 2008): -17.27%

As of September 30, 2013, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 13.28%.

Year to Date Return, Label

rr_YearToDateReturnLabel

Investor Class year-to-date

Bar Chart, Year to Date Return, Date

rr_BarChartYearToDateReturnDate

Sep. 30, 2013

Bar Chart, Year to Date Return

rr_BarChartYearToDateReturn

13.28%

Highest Quarterly Return, Label

rr_HighestQuarterlyReturnLabel

Highest Performance Quarter

Highest Quarterly Return, Date

rr_BarChartHighestQuarterlyReturnDate

Jun. 30, 2003

Highest Quarterly Return

rr_BarChartHighestQuarterlyReturn

17.77%

Lowest Quarterly Return, Label

rr_LowestQuarterlyReturnLabel

Lowest Performance Quarter

Lowest Quarterly Return, Date

rr_BarChartLowestQuarterlyReturnDate

Sep. 30, 2008

Lowest Quarterly Return

rr_BarChartLowestQuarterlyReturn

(17.27%)

Performance Table Heading

rr_PerformanceTableHeading

Average Annual Total Returns For the calendar year ended December 31, 2012

Performance Table Uses Highest Federal Rate

rr_PerformanceTableUsesHighestFederalRate

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes.

Performance Table Not Relevant to Tax Deferred

rr_PerformanceTableNotRelevantToTaxDeferred

Actual after-tax returns depend on an investor's tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

Performance Table Closing [Text Block]

rr_PerformanceTableClosingTextBlock

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

UTILITIES FUND | S&P 500® Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

16.00%

5 years

rr_AverageAnnualReturnYear05

1.66%

10 years

rr_AverageAnnualReturnYear10

7.10%

UTILITIES FUND | Russell 3000 Utilities Index (reflects no deduction for fees, expenses or taxes)

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

7.67%

5 years

rr_AverageAnnualReturnYear05

1.47%

10 years

rr_AverageAnnualReturnYear10

8.32%

UTILITIES FUND | INVESTOR CLASS

Prospectus [Line Items]

rr_ProspectusLineItems

Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)

rr_MaximumAccountFee

25

Management Fee

rr_ManagementFeesOverAssets

0.67%

Distribution and Service (12b-1) Fees

rr_DistributionAndService12b1FeesOverAssets

none

Other Expenses

rr_OtherExpensesOverAssets

0.01%

Total Annual Fund Operating Expenses

rr_ExpensesOverAssets

0.68%

1 year

rr_ExpenseExampleYear01

70

3 years

rr_ExpenseExampleYear03

218

5 years

rr_ExpenseExampleYear05

379

10 years

rr_ExpenseExampleYear10

$ 847

Annual Return 2003

rr_AnnualReturn2003

23.96%

Annual Return 2004

rr_AnnualReturn2004

23.81%

Annual Return 2005

rr_AnnualReturn2005

14.30%

Annual Return 2006

rr_AnnualReturn2006

24.99%

Annual Return 2007

rr_AnnualReturn2007

17.82%

Annual Return 2008

rr_AnnualReturn2008

(31.12%)

Annual Return 2009

rr_AnnualReturn2009

14.48%

Annual Return 2010

rr_AnnualReturn2010

11.14%

Annual Return 2011

rr_AnnualReturn2011

11.12%

Annual Return 2012

rr_AnnualReturn2012

4.26%

1 year

rr_AverageAnnualReturnYear01

4.26%

5 years

rr_AverageAnnualReturnYear05

0.30%

10 years

rr_AverageAnnualReturnYear10

10.11%

UTILITIES FUND | INVESTOR CLASS | Return After Taxes on Distributions

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

2.82%

5 years

rr_AverageAnnualReturnYear05

(0.41%)

10 years

rr_AverageAnnualReturnYear10

9.50%

UTILITIES FUND | INVESTOR CLASS | Return After Taxes on Distributions and Sale of Fund Shares

Prospectus [Line Items]

rr_ProspectusLineItems

1 year

rr_AverageAnnualReturnYear01

4.71%

5 years

rr_AverageAnnualReturnYear05

0.20%

10 years

rr_AverageAnnualReturnYear10

8.93%

[1] Investments of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of the purchase.

[2] Prior to September 4, 2007, this class was referred to as the Advisor Class and did not have a front-end sales charge. Performance has been restated to reflect this charge.

[3] Other Expenses are based on estimated amounts for the current fiscal year.

[4] The advisor has agreed to waive 0.07 percentage points of the fund's management fee. The advisor expects this waiver to continue for one year from the date of this prospectus, and cannot terminate it prior to such date without the approval of the Board of Directors.

[5] NYSE Arca Gold Miners Index benchmark total return data is first available as of October 1, 2004.

[6] The advisor has agreed to waive 0.20 percentage points of the fund's management fee. The advisor expects this waiver to continue until October 31, 2014, and cannot terminate it prior to such date without the approval of the Board of Directors.

[7] Prior to March 1, 2010, the A Class was referred to as the Advisor Class and did not have a front-end sales charge. Performance prior to that date has been restated to reflect this charge.

[8] Historical performance for C Class prior to its inception is based on the performance of Investor Class shares. C Class performance has been adjusted to reflect differences in sales charges, if applicable, and expenses between classes.

XML

CORE EQUITY PLUS FUND

CORE EQUITY PLUS FUND

Investment Objective

The fund seeks long-term capital growth.

Fees and Expenses

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 13 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees CORE EQUITY PLUS FUND (USD $)	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS		C CLASS	R CLASS
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none	none	5.75%		none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the original offering price or redemption proceeds when redeemed within one year of purchase)	none	none	none	[1]	1.00%	none
Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)	25	none	none		none	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses CORE EQUITY PLUS FUND	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS	C CLASS	R CLASS
Management Fee	1.30%	1.10%	1.30%	1.30%	1.30%
Distribution and Service (12b-1) Fees	none	none	0.25%	1.00%	0.50%
Dividends on Short Sales	0.32%	0.32%	0.32%	0.32%	0.32%
Broker Fees and Charges on Short Sales	0.25%	0.25%	0.25%	0.25%	0.25%
Other	none	none	none	none	none
Other Expenses	0.57%	0.57%	0.57%	0.57%	0.57%
Total Annual Fund Operating Expenses	1.87%	1.67%	2.12%	2.87%	2.37%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn 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 CORE EQUITY PLUS FUND (USD $)	1 year	3 years	5 years	10 years
INVESTOR CLASS	190	589	1,012	2,188
INSTITUTIONAL CLASS	170	527	908	1,974
A CLASS	778	1,202	1,649	2,882
C CLASS	291	890	1,514	3,188
R CLASS	241	741	1,266	2,702

Portfolio Turnover

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 107% of the average value of its portfolio.

Principal Investment Strategies

The managers use quantitative models to construct the portfolio of equity securities for the fund. The fund invests approximately 130% of its assets in long positions, while 30% of its assets are sold short. A long position arises when the fund buys a security outright. A short position arises when the fund sells a security it does not own but has borrowed in anticipation that the market price of the security will decline. If the market price in fact declines, the fund can replace the borrowed security at a lower price and capture the value represented by the difference between the higher sale price and the lower replacement price. The proceeds from the securities sold short are used to purchase an additional 30% of long positions. The net investment exposure for the fund is a 100% long market exposure.

The portfolio managers buy, or take long positions in, equity securities that they have identified as the most attractive and take short positions in equity securities that they have identified as the least attractive using a multi-factor quantitative model in a two-step process. In the first step, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from the most attractive to least attractive based on an objective set of measures, including a stock’s value, quality, growth, and momentum. In the second step, the managers use a quantitative model to build a portfolio that provides the optimal balance between risk and expected return.

The portfolio managers generally sell a stock from the fund's long portfolio when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

The fund’s use of short selling as a primary investment strategy creates leverage in an attempt to increase returns.

Principal Risks

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Short Sales Risk - If the market price of a security increases after the fund borrows the security, the fund may suffer a loss when it replaces the borrowed security at the higher price. Any loss will be increased by the amount of compensation, interest or dividends, and transaction costs the fund must pay to the lender of the borrowed security.

• Leverage Risk - The fund’s investment strategy utilizes leverage, which can increase market exposure and subject the fund to greater risk and higher volatility.

• Overweighting Risk - If the fund is overweighted in a stock or sector, any negative development related to that stock or sector will have a greater impact on the fund than other funds that are not overweighted in that stock or sector.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the S&P 500^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

Highest Performance Quarter (1Q 2012): 13.42%  

Lowest Performance Quarter (2Q 2012): -4.00%

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was 21.70%.

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns CORE EQUITY PLUS FUND	1 year	Since Inception	Inception Date
INVESTOR CLASS	16.43%	13.05%	Oct. 31, 2011
INVESTOR CLASS Return After Taxes on Distributions	15.87%	12.58%	Oct. 31, 2011
INVESTOR CLASS Return After Taxes on Distributions and Sale of Fund Shares	11.10%	10.99%	Oct. 31, 2011
INSTITUTIONAL CLASS	16.66%	13.28%	Oct. 31, 2011
A CLASS	9.51%	7.21%	Oct. 31, 2011
C CLASS	15.35%	11.92%	Oct. 31, 2011
R CLASS	15.88%	12.45%	Oct. 31, 2011
S&P 500® Index (reflects no deduction for fees, expenses or taxes)	16.00%	14.35%	Oct. 31, 2011

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

DISCIPLINED GROWTH PLUS FUND

DISCIPLINED GROWTH PLUS FUND

Investment Objective

The fund seeks long-term capital growth.

Fees and Expenses

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 13 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees DISCIPLINED GROWTH PLUS FUND (USD $)	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS		C CLASS	R CLASS
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none	none	5.75%		none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the original offering price or redemption proceeds when redeemed within one year of purchase)	none	none	none	[1]	1.00%	none
Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)	25	none	none		none	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses DISCIPLINED GROWTH PLUS FUND	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS	C CLASS	R CLASS
Management Fee	1.45%	1.25%	1.45%	1.45%	1.45%
Distribution and Service (12b-1) Fees	none	none	0.25%	1.00%	0.50%
Dividends on Short Sales	0.17%	0.17%	0.17%	0.17%	0.17%
Broker Fees and Charges on Short Sales	0.24%	0.24%	0.24%	0.24%	0.24%
Other	0.01%	0.01%	0.01%	0.01%	0.01%
Other Expenses	0.42%	0.42%	0.42%	0.42%	0.42%
Total Annual Fund Operating Expenses	1.87%	1.67%	2.12%	2.87%	2.37%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn 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 DISCIPLINED GROWTH PLUS FUND (USD $)	1 year	3 years	5 years	10 years
INVESTOR CLASS	190	589	1,012	2,188
INSTITUTIONAL CLASS	170	527	908	1,974
A CLASS	778	1,202	1,649	2,882
C CLASS	291	890	1,514	3,188
R CLASS	241	741	1,266	2,702

Portfolio Turnover

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 100% of the average value of its portfolio.

Principal Investment Strategies

The managers use quantitative models to construct the portfolio of equity securities for the fund. The fund invests approximately 130% of its assets in long positions, while 30% of its assets are sold short. A long position arises when the fund buys a security outright. A short position arises when the fund sells a security it does not own but has borrowed in anticipation that the market price of the security will decline. If the market price in fact declines, the fund can replace the borrowed security at a lower price and capture the value represented by the difference between the higher sale price and the lower replacement price. The proceeds from the securities sold short are used to fund the purchase of the additional 30% of long positions. The net investment exposure for the fund is a 100% long market exposure.

The portfolio managers initially identify an eligible universe of growth stocks and then buy, or take long positions in, equity securities that they have identified as the most attractive and take short positions in equity securities that they have identified as the least attractive using a multi-factor quantitative model in a two-step process. In the first step, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from most to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. In the second step, the managers use a quantitative model to build a portfolio that provides the optimal balance between risk and expected return.

The portfolio managers generally sell a stock from the fund's long portfolio when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

The fund’s use of short selling as a primary investment strategy creates leverage in an attempt to increase returns.

Principal Risks

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Short Sales Risk - If the market price of a security increases after the fund borrows the security, the fund may suffer a loss when it replaces the borrowed security at the higher price. Any loss will be increased by the amount of compensation, interest or dividends, and transaction costs the fund must pay to the lender of the borrowed security.

• Leverage Risk - The fund’s investment strategy utilizes leverage, which can increase market exposure and subject the fund to greater risk and higher volatility.

• Overweighting Risk - If the fund is overweighted in a stock or sector, any negative development related to that stock or sector will have a greater impact on the fund than other funds that are not overweighted in that stock or sector.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the Russell 1000^® Growth Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Growth Stocks - Investments in growth stocks may involve special risks and their prices tend to fluctuate more dramatically than the overall stock market.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

Highest Performance Quarter (1Q 2012): 17.14%  

Lowest Performance Quarter (2Q 2012): -5.40%

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was 22.09%.

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns DISCIPLINED GROWTH PLUS FUND	1 year	Since Inception	Inception Date
INVESTOR CLASS	15.66%	11.42%	Oct. 31, 2011
INVESTOR CLASS Return After Taxes on Distributions	15.56%	11.32%	Oct. 31, 2011
INVESTOR CLASS Return After Taxes on Distributions and Sale of Fund Shares	10.31%	9.72%	Oct. 31, 2011
INSTITUTIONAL CLASS	15.89%	11.64%	Oct. 31, 2011
A CLASS	8.72%	5.66%	Oct. 31, 2011
C CLASS	14.50%	10.26%	Oct. 31, 2011
R CLASS	15.09%	10.87%	Oct. 31, 2011
Russell 1000® Growth Index (reflects no deduction for fees, expenses or taxes)	15.26%	12.62%	Oct. 31, 2011

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

DISCIPLINED GROWTH FUND

DISCIPLINED GROWTH FUND

Investment Objective

The fund seeks long-term capital growth.

Fees and Expenses

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 13 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees DISCIPLINED GROWTH FUND (USD $)	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS		C CLASS	R CLASS
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none	none	5.75%		none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the original offering price or redemption proceeds when redeemed within one year of purchase)	none	none	none	[1]	1.00%	none
Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)	25	none	none		none	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses DISCIPLINED GROWTH FUND	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS	C CLASS	R CLASS
Management Fee	1.02%	0.82%	1.02%	1.02%	1.02%
Distribution and Service (12b-1) Fees	none	none	0.25%	1.00%	0.50%
Other Expenses	0.01%	0.01%	0.01%	0.01%	0.01%
Total Annual Fund Operating Expenses	1.03%	0.83%	1.28%	2.03%	1.53%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn 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 DISCIPLINED GROWTH FUND (USD $)	1 year	3 years	5 years	10 years
INVESTOR CLASS	105	328	569	1,259
INSTITUTIONAL CLASS	85	265	461	1,026
A CLASS	698	958	1,238	2,031
C CLASS	207	638	1,094	2,355
R CLASS	156	484	835	1,822

Portfolio Turnover

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 94% of the average value of its portfolio.

Principal Investment Strategies

In selecting stocks for the fund, the portfolio managers initially identify an eligible universe of growth stocks then use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Principal Risks

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk- Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the Russell 1000^® Growth Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Growth Stocks - Investments in growth stocks may involve special risks and their prices tend to fluctuate more dramatically than the overall stock market.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

Highest Performance Quarter (1Q 2012): 17.16%  

Lowest Performance Quarter (4Q 2008): -23.62%  

As of September 30, 2013, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 21.84%.

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns DISCIPLINED GROWTH FUND		1 year	5 years	Since Inception	Inception Date
INVESTOR CLASS		15.72%	2.84%	5.69%	Sep. 30, 2005
INVESTOR CLASS Return After Taxes on Distributions		15.56%	2.76%	5.46%	Sep. 30, 2005
INVESTOR CLASS Return After Taxes on Distributions and Sale of Fund Shares		10.42%	2.42%	4.86%	Sep. 30, 2005
INSTITUTIONAL CLASS		15.91%	3.06%	5.90%	Sep. 30, 2005
A CLASS	[1]	8.86%	1.40%	4.58%	Sep. 30, 2005
C CLASS		14.61%	1.83%	1.56%	Sep. 28, 2007
R CLASS		15.12%	2.34%	5.17%	Sep. 30, 2005
Russell 1000® Growth Index (reflects no deduction for fees, expenses or taxes)		15.26%	3.12%	5.41%	Sep. 30, 2005

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

EMERGING MARKETS VALUE FUND

EMERGING MARKETS VALUE FUND

Investment Objective

The fund seeks capital growth.

Fees and Expenses

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees EMERGING MARKETS VALUE FUND (USD $)	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS		C CLASS	R CLASS
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none	none	5.75%		none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the original offering price or redemption proceeds when redeemed within one year of purchase)	none	none	none	[1]	1.00%	none
Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)	25	none	none		none	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses EMERGING MARKETS VALUE FUND		INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS	C CLASS	R CLASS
Management Fee		1.52%	1.32%	1.52%	1.52%	1.52%
Distribution and Service (12b-1) Fees		none	none	0.25%	1.00%	0.50%
Other Expenses	[1]	0.01%	0.01%	0.01%	0.01%	0.01%
Total Annual Fund Operating Expenses		1.53%	1.33%	1.78%	2.53%	2.03%
Fee Waiver	[2]	0.07%	0.07%	0.07%	0.07%	0.07%
Total Annual Fund Operating Expenses After Waiver		1.46%	1.26%	1.71%	2.46%	1.96%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods (unless otherwise indicated), that you earn 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 EMERGING MARKETS VALUE FUND (USD $)	1 year	3 years
INVESTOR CLASS	149	477
INSTITUTIONAL CLASS	129	415
A CLASS	739	1,097
C CLASS	250	782
R CLASS	199	631

Portfolio Turnover

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. Because the fund is new, the fund’s portfolio turnover is not available.

Principal Investment Strategies

In selecting stocks for the fund, the portfolio managers select primarily from publicly-traded companies of all sizes located in the emerging market countries that comprise the MSCI Emerging Markets Index.

The MSCI Emerging Markets Index is a market capitalization-weighted index that monitors, as of the date of this prospectus, the performance of value stocks in the following emerging markets countries: Brazil, Chile, China, Colombia, Czech Republic, Egypt, Greece, Hungary, India, Indonesia, Korea, Malaysia, Mexico, Peru, Philippines, Poland, Russia, South Africa, Taiwan, Thailand and Turkey.

The managers use quantitative models in a two-step process to construct the portfolio of stocks for the fund. First, the managers rank stocks from most attractive to least attractive based on each stock’s value, momentum, and quality, as well as its growth potential. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Under normal market conditions, at least 80% of the fund's net assets will be invested in emerging market securities.

Principal Risks

• Foreign Securities Risk - The fund invests primarily in foreign securities, which are generally riskier than U.S. securities. As a result, the fund is subject to foreign risk, meaning that political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), and natural disasters occurring in a country where the fund invests could cause the fund’s investments in that country to experience gains or losses. Because of these risks, and others, securities of foreign issuers may be less liquid, more volatile, and harder to value than U.S. securities.

• Emerging Market Risk - Investing in securities of companies located in emerging market countries generally is also riskier than investing in securities of companies located in foreign developed countries. Emerging market countries may have unstable governments and/or economies that are subject to sudden change. These changes may be magnified by the countries’ emergent financial markets, resulting in significant volatility to investments in these countries. These countries also may lack the legal, business and social framework to support securities markets.

• Currency Risk - Because the fund generally invests in securities denominated in foreign currencies, the fund is subject to currency risk, meaning that the fund could experience gains or losses based solely on changes in the exchange rate between foreign currencies and the U.S. dollar.

• Style Risk - If at any time the market is not favoring the fund’s value or quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Benchmark Correlation - The fund’s performance will likely be similar to the performance of its benchmark, the MSCI Emerging Markets Value Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Quantitative Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers’ judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors’ historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Small and Mid Cap Stocks - The fund may invest in mid-sized and smaller companies, which may be more volatile and subject to greater risk than larger companies. Smaller companies may have limited financial resources, product lines and markets, and their securities may trade less frequently and in more limited volumes than the securities of larger companies, which could lead to higher transaction costs.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The fund’s performance history is not available as of the date of this prospectus. When the fund has investment results for a full calendar year, this section will feature charts that show annual total returns, highest and lowest quarterly returns and average annual total returns for the fund. This information indicates the volatility of the fund’s historical returns from year to year.

Performance information is designed to help you see how fund returns can vary. Keep in mind that past performance (before and after taxes) does not predict how the fund will perform in the future.

For current performance information, please visit americancentury.com.

EQUITY MARKET NEUTRAL FUND

EQUITY MARKET NEUTRAL FUND

Investment Objective

The fund seeks capital appreciation independent of equity market conditions.

Fees and Expenses

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 14 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees EQUITY MARKET NEUTRAL FUND (USD $)	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS		C CLASS	R CLASS
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none	none	5.75%		none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the original offering price or redemption proceeds when redeemed within one year of purchase)	none	none	none	[1]	1.00%	none
Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)	25	none	none		none	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses EQUITY MARKET NEUTRAL FUND	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS	C CLASS	R CLASS
Management Fee	1.38%	1.18%	1.38%	1.38%	1.38%
Distribution and Service (12b-1) Fees	none	none	0.25%	1.00%	0.50%
Dividends on Short Sales	1.41%	1.41%	1.41%	1.41%	1.41%
Broker Fees and Charges on Short Sales	0.27%	0.27%	0.27%	0.27%	0.27%
Other	0.01%	0.01%	0.01%	0.01%	0.01%
Other Expenses	1.69%	1.69%	1.69%	1.69%	1.69%
Total Annual Fund Operating Expenses	3.07%	2.87%	3.32%	4.07%	3.57%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn 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 EQUITY MARKET NEUTRAL FUND (USD $)	1 year	3 years	5 years	10 years
INVESTOR CLASS	311	950	1,612	3,376
INSTITUTIONAL CLASS	291	890	1,514	3,188
A CLASS	891	1,539	2,208	3,972
C CLASS	410	1,240	2,084	4,254
R CLASS	361	1,096	1,851	3,827

Portfolio Turnover

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 222% of the average value of its portfolio.

Principal Investment Strategies

The managers use quantitative models to construct the portfolio for the fund. The portfolio managers buy, or take long positions in, equity securities that they have identified as undervalued. They take short positions in equity securities that they have identified as overvalued.  A short position arises when the fund sells a security it does not own but has borrowed in anticipation that the market price of the security will decline. If the market price in fact declines, the fund can replace the borrowed security at a lower price and capture the value represented by the difference between the higher sale price and the lower replacement price. The fund’s investment process is designed to maintain approximately equal dollar amounts invested in long and short positions at all times. By employing this market neutral strategy, the fund seeks to limit market risk (the effects of general market movements on the fund’s performance). A market neutral strategy seeks to limit the fund’s volatility relative to the market. As a result of this strategy, the portfolio’s price movements are not expected to correlate with the market’s price movements.

In selecting stocks for the fund, the portfolio managers use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily publicly traded U.S. companies with a market capitalization greater than $1 billion, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity, or specific events alter its prospects.

Principal Risks

• Management Risk - Although the fund seeks to have approximately equal dollar amounts invested in long and short positions and a neutral exposure to market movements, there is a risk that the portfolio managers will not be able to construct a portfolio of long and short positions that has limited exposure to general market movements.

• Investment Process Risk- Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Failure to Maintain Market Neutrality - Though the fund seeks to limit risks associated with investing in the general equity market, external conditions may impact the fund’s performance. In addition, although the portfolio managers intend to construct a market neutral portfolio, there is a risk that the portfolio managers will not construct a portfolio that limits exposure to general market movements.

• Style Risk - Because the fund’s portfolio may not always be style-neutral, its performance may be sensitive to the value/growth cycle within the U.S. equity markets. Also, if at any time the market is not favoring the fund’s quantitative style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Short Sales Risk - If the market price of a security increases after the fund borrows the security, the fund may suffer a loss when it replaces the borrowed security at the higher price. Any loss will be increased by the amount of compensation, interest or dividends, and transaction costs the fund must pay to a lender of the security.

• Overweighting Risk - If the fund is overweighted in a stock or sector, any negative development related to that stock or sector will have a greater impact on the fund than other funds that are not overweighted in that stock or sector.

• Small Cap Stocks - Though the fund invests primarily in larger companies, it may also invest in smaller companies. Investments in smaller companies may be more volatile and subject to greater risk than larger companies. Smaller companies may have limited financial resources, product lines and markets, and their securities may trade less frequently and in more limited volumes than the securities of larger companies, which could lead to higher transaction costs.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities the fund owns in its long portfolio or in which the fund has taken a short position.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time, your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

Highest Performance Quarter (2Q 2006): 10.73% 

Lowest Performance Quarter (3Q 2008): -6.78%

As of September 30, 2013, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 3.43%.

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns EQUITY MARKET NEUTRAL FUND	1 year	5 years	Since Inception	Inception Date
INVESTOR CLASS	(1.22%)	(0.89%)	1.07%	Sep. 30, 2005
INVESTOR CLASS Return After Taxes on Distributions	(1.22%)	(0.89%)	0.97%	Sep. 30, 2005
INVESTOR CLASS Return After Taxes on Distributions and Sale of Fund Shares	(0.79%)	(0.75%)	0.88%	Sep. 30, 2005
INSTITUTIONAL CLASS	(1.12%)	(0.70%)	1.27%	Sep. 30, 2005
A CLASS	(7.25%)	(2.33%)	none	Sep. 30, 2005
C CLASS	(2.27%)	(1.89%)	0.06%	Sep. 30, 2005
R CLASS	(1.73%)	(1.39%)	0.57%	Sep. 30, 2005
Barclays U.S. 1-3 Month Treasury Bill Index (reflects no deduction for fees, expenses or taxes)	0.08%	0.44%	1.73%	Sep. 30, 2005

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

EQUITY GROWTH FUND

EQUITY GROWTH FUND

Investment Objective

The fund seeks long-term capital growth by investing in common stocks.

Fees and Expenses

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees EQUITY GROWTH FUND (USD $)	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS		C CLASS	R CLASS
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none	none	5.75%		none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the original offering price or redemption proceeds when redeemed within one year of purchase)	none	none	none	[1]	1.00%	none
Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)	25	none	none		none	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses EQUITY GROWTH FUND	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS	C CLASS	R CLASS
Management Fee	0.67%	0.47%	0.67%	0.67%	0.67%
Distribution and Service (12b-1) Fees	none	none	0.25%	1.00%	0.50%
Other Expenses	0.01%	0.01%	0.01%	0.01%	0.01%
Total Annual Fund Operating Expenses	0.68%	0.48%	0.93%	1.68%	1.18%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn 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 EQUITY GROWTH FUND (USD $)	1 year	3 years	5 years	10 years
INVESTOR CLASS	70	218	379	847
INSTITUTIONAL CLASS	49	154	269	604
A CLASS	665	855	1,061	1,652
C CLASS	171	530	913	1,985
R CLASS	121	375	650	1,431

Portfolio Turnover

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 94% of the average value of its portfolio.

Principal Investment Strategies

In selecting stocks for the fund, the portfolio managers use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

Under normal market conditions, at least 80% of the fund’s net assets will be invested in equity securities.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Principal Risks

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk- Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the S&P 500^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

Highest Performance Quarter (2Q 2003): 15.14% 

Lowest Performance Quarter (4Q 2008): -21.63%

As of September 30, 2013, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 19.72%.

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns EQUITY GROWTH FUND		1 year	5 years	10 years	Since Inception	Inception Date
INVESTOR CLASS		16.32%	1.73%	7.43%		May 09, 1991
INVESTOR CLASS Return After Taxes on Distributions		16.00%	1.50%	7.02%		May 09, 1991
INVESTOR CLASS Return After Taxes on Distributions and Sale of Fund Shares		11.01%	1.43%	6.49%		May 09, 1991
INSTITUTIONAL CLASS		16.54%	1.93%	7.64%		Jan. 02, 1998
A CLASS	[1]	9.31%	0.28%	6.54%		Oct. 09, 1997
C CLASS		15.14%	0.72%	6.39%		Jul. 18, 2001
R CLASS		15.75%	1.22%		3.12%	Jul. 29, 2005
S&P 500® Index (reflects no deduction for fees, expenses or taxes)		16.00%	1.66%	7.10%

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

GLOBAL GOLD FUND

GLOBAL GOLD FUND

Investment Objective

The fund seeks to realize a total return (capital growth and dividends) consistent with investment in securities of companies that are engaged in mining, processing, fabricating or distributing gold or other precious metals throughout the world.

Fees and Expenses

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees GLOBAL GOLD FUND (USD $)	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS		C CLASS	R CLASS
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none	none	5.75%		none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the original offering price or redemption proceeds when redeemed within one year of purchase)	none	none	none	[1]	1.00%	none
Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)	25	none	none		none	none
Redemption/Exchange Fee (as a percentage of amount redeemed/exchanged for shares held less than 60 days)	1.00%	1.00%	none		none	1.00%

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses GLOBAL GOLD FUND	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS	C CLASS	R CLASS
Management Fee	0.67%	0.47%	0.67%	0.67%	0.67%
Distribution and Service (12b-1) Fees	none	none	0.25%	1.00%	0.50%
Other Expenses	0.01%	0.01%	0.01%	0.01%	0.01%
Total Annual Fund Operating Expenses	0.68%	0.48%	0.93%	1.68%	1.18%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods (unless otherwise indicated), that you earn 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 GLOBAL GOLD FUND (USD $)	1 year	3 years	5 years	10 years
INVESTOR CLASS	70	218	379	847
INSTITUTIONAL CLASS	49	154	269	604
A CLASS	665	855	1,061	1,652
C CLASS	171	530	913	1,985
R CLASS	121	375	650	1,431

Portfolio Turnover

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 6% of the average value of its portfolio.

Principal Investment Strategies

The fund invests at least 80% of its net assets in companies that are engaged in mining, processing, fabricating, distributing, exploring for or otherwise dealing in gold. The portfolio managers use quantitative management techniques and fundamental stock selection in a two-step process to construct the portfolio of stocks for the fund. First, the managers select stocks based on several valuation criteria, without comparing the fund’s holdings to the holdings of an index or benchmark. Second, the managers use a quantitative model to assess the fund’s risk characteristics relative to its benchmark and help the managers build a portfolio of stocks that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Principal Risks

• Gold Stocks - Gold stocks are generally considered speculative because of high share price volatility. The price of gold will likely impact the value of the companies in which the fund invests. The price of gold will fluctuate, sometimes considerably. Though many investors believe that gold investments hedge against inflation, currency devaluations and stock market declines, there is no guarantee that these historical inverse relationships will continue.

• Nondiversification - The fund is classified as nondiversified. A nondiversified fund may invest a greater percentage of its assets in a smaller number of securities than a diversified fund. This gives the managers the flexibility to hold large positions in a small number of securities. If so, a price change in any one of those securities may have a greater impact on the fund's share price than would be the case in a diversified fund and the fund may be more volatile than if it was diversified.

• Concentration Risk - The fund concentrates its investments in a specific area and therefore may be subject to greater risks and market fluctuations than a portfolio representing a broader range of industries.

• Foreign Securities Risk - The fund invests primarily in foreign securities, which are generally riskier than U.S. stocks. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.

• Emerging Markets Risk -Investing in securities of companies located in emerging market countries generally is riskier than investing in securities of companies located in foreign developed countries.

• Currency Risk - Because the fund invests in securities denominated in foreign currencies, the fund is subject to currency risk, meaning that the fund could experience gains or losses based solely on changes in the exchange rate between foreign currencies and the U.S. dollar.

• Market Risk - The value of the fund's shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund's shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The table also shows returns for the NYSE Arca Gold Miners Index, which is a modified market capitalization-weighted index comprised of publicly traded companies involved primarily in mining for gold and silver. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

Highest Performance Quarter (3Q 2012): 22.78%  

Lowest Performance Quarter (3Q 2008): -29.72%

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was -42.96%.

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns GLOBAL GOLD FUND		1 year	5 years	10 years	Since Inception	Inception Date
INVESTOR CLASS		(7.86%)	2.34%	11.06%		Aug. 17, 1988
INVESTOR CLASS Return After Taxes on Distributions		(8.04%)	1.12%	10.29%		Aug. 17, 1988
INVESTOR CLASS Return After Taxes on Distributions and Sale of Fund Shares		(4.93%)	1.74%	9.71%		Aug. 17, 1988
INSTITUTIONAL CLASS		(7.66%)	2.56%		3.12%	Sep. 28, 2007
A CLASS	[1]	(13.34%)	0.89%	10.13%		May 06, 1998
C CLASS		(8.80%)	1.32%		1.89%	Sep. 28, 2007
R CLASS		(8.30%)	1.83%		2.40%	Sep. 28, 2007
MSCI World Index (reflects no deduction for fees, expenses or taxes)		15.83%	(1.18%)	7.51%
NYSE Arca Gold Miners Index (reflects no deduction for fees, expenses or taxes)	[2]	(8.46%)	1.16%

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

INTERNATIONAL CORE EQUITY FUND

INTERNATIONAL CORE EQUITY FUND

Investment Objective

The fund seeks long-term capital growth.

Fees and Expenses

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees INTERNATIONAL CORE EQUITY FUND (USD $)	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS		C CLASS	R CLASS
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none	none	5.75%		none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the original offering price or redemption proceeds when redeemed within one year of purchase)	none	none	none	[1]	1.00%	none
Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)	25	none	none		none	none
Redemption/Exchange Fee (as a percentage of amount redeemed/exchanged for shares held less than 60 days)	2.00%	2.00%	none		none	2.00%

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses INTERNATIONAL CORE EQUITY FUND	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS	C CLASS	R CLASS
Management Fee	1.15%	0.95%	1.15%	1.15%	1.15%
Distribution and Service (12b-1) Fees	none	none	0.25%	1.00%	0.50%
Other Expenses	0.01%	0.01%	0.01%	0.01%	0.01%
Total Annual Fund Operating Expenses	1.16%	0.96%	1.41%	2.16%	1.66%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods (unless otherwise indicated), that you earn 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 INTERNATIONAL CORE EQUITY FUND (USD $)	1 year	3 years	5 years	10 years
INVESTOR CLASS	118	369	639	1,409
INSTITUTIONAL CLASS	98	306	532	1,178
A CLASS	711	996	1,302	2,168
C CLASS	220	677	1,160	2,489
R CLASS	169	524	903	1,964

Portfolio Turnover

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 101% of the average value of its portfolio.

Principal Investment Strategies

In selecting stocks for the fund, the portfolio managers select from publicly traded companies that are primarily located in developed countries, excluding the United States and Canada, that have characteristics similar to those of the companies that comprise the MSCI EAFE^® (Europe, Australasia, Far East) Index. The managers use quantitative models in a two-step process to construct the portfolio of stocks for the fund. First, the portfolio managers rank stocks from most attractive to least attractive by using a quantitative model that combines measures that the portfolio managers believe are predictive of an individual stock performance, such as value, quality and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

The portfolio managers also intend to spread the fund’s holdings across different countries and geographic regions in an effort to manage the risks of an international portfolio. Though the fund invests primarily in securities issued by companies located in developed countries, it may also invest in emerging markets.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Under normal market conditions, at least 80% of the fund's net assets will be invested in equity securities.

Principal Risks

• Foreign Securities Risk - The fund invests primarily in foreign securities, which are generally riskier than U.S. securities. As a result, the fund is subject to foreign risk, meaning that political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), and natural disasters occurring in a country where the fund invests could cause the fund’s investments in that country to experience gains or losses. Because of these risks, and others, securities of foreign issuers may be less liquid, more volatile, and harder to value than U.S. securities.

• Emerging Markets Risk - Investing in securities of companies located in emerging market countries generally is riskier than investing in securities of companies located in foreign developed countries.

• Currency Risk - Because the fund generally invests in securities denominated in foreign currencies, the fund is subject to currency risk, meaning that the fund could experience gains or losses based solely on changes in the exchange rate between foreign currencies and the U.S. dollar.

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Benchmark Correlation - The fund’s performance will likely be similar to the performance of its benchmark, the MSCI EAFE^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Small and Mid Cap Stocks - The fund may invest in mid-sized and smaller companies, which may be more volatile and subject to greater risk than larger companies. Smaller companies may have limited financial resources, product lines and markets, and their securities may trade less frequently and in more limited volumes than the securities of larger companies, which could lead to higher transaction costs.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

Highest Performance Quarter (2Q 2009): 21.59%

Lowest Performance Quarter (3Q 2008): -22.12%

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was 18.50%.

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns INTERNATIONAL CORE EQUITY FUND	1 year	5 years	Since Inception	Inception Date
INVESTOR CLASS	17.98%	(4.55%)	(1.70%)	Nov. 30, 2006
INVESTOR CLASS Return After Taxes on Distributions	17.74%	(4.70%)	(2.16%)	Nov. 30, 2006
INVESTOR CLASS Return After Taxes on Distributions and Sale of Fund Shares	12.77%	(3.64%)	(1.43%)	Nov. 30, 2006
INSTITUTIONAL CLASS	18.37%	(4.33%)	(1.49%)	Nov. 30, 2006
A CLASS	10.98%	(5.91%)	(2.89%)	Nov. 30, 2006
C CLASS	16.88%	(5.49%)	(2.67%)	Nov. 30, 2006
R CLASS	17.61%	(5.02%)	(2.17%)	Nov. 30, 2006
MSCI EAFE® Index (reflects no deduction for fees, expenses or taxes)	17.32%	(3.69%)	(0.84%)	Nov. 30, 2006

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

INCOME & GROWTH FUND

INCOME & GROWTH FUND

Investment Objective

The fund seeks long-term capital growth by investing in common stocks.

Income is a secondary objective.

Fees and Expenses

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees INCOME & GROWTH FUND (USD $)	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS		C CLASS	R CLASS
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none	none	5.75%		none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the original offering price or redemption proceeds when redeemed within one year of purchase)	none	none	none	[1]	1.00%	none
Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)	25	none	none		none	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses INCOME & GROWTH FUND	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS	C CLASS	R CLASS
Management Fee	0.67%	0.47%	0.67%	0.67%	0.67%
Distribution and Service (12b-1) Fees	none	none	0.25%	1.00%	0.50%
Other Expenses	0.01%	0.01%	0.01%	0.01%	0.01%
Total Annual Fund Operating Expenses	0.68%	0.48%	0.93%	1.68%	1.18%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn 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 INCOME & GROWTH FUND (USD $)	1 year	3 years	5 years	10 years
INVESTOR CLASS	70	218	379	847
INSTITUTIONAL CLASS	49	154	269	604
A CLASS	665	855	1,061	1,652
C CLASS	171	530	913	1,985
R CLASS	121	375	650	1,431

Portfolio Turnover

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 74% of the average value of its portfolio.

Principal Investment Strategies

In selecting stocks for the fund, the portfolio managers use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum (with a tilt towards value). Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return. The portfolio managers also attempt to create a dividend yield that will be greater than the S&P 500^® Index.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Principal Risks

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the S&P 500^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Low Dividend Yield - Although current income is an objective of the fund, if the stocks that make up the S&P 500^® Index do not have a high dividend yield, then the fund’s dividend yield will not be high.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

Highest Performance Quarter (2Q 2003): 16.41% 

Lowest Performance Quarter (4Q 2008): -19.93% 

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was 22.04%. 

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns INCOME & GROWTH FUND		1 year	5 years	10 years	Since Inception	Inception Date
INVESTOR CLASS		14.52%	0.73%	6.39%		Dec. 17, 1990
INVESTOR CLASS Return After Taxes on Distributions		14.16%	0.45%	5.70%		Dec. 17, 1990
INVESTOR CLASS Return After Taxes on Distributions and Sale of Fund Shares		9.90%	0.57%	5.48%		Dec. 17, 1990
INSTITUTIONAL CLASS		14.78%	0.93%	6.60%		Jan. 28, 1998
A CLASS	[1]	7.74%	(0.70%)	5.51%		Dec. 15, 1997
C CLASS		13.43%	(0.26%)	5.36%		Jun. 28, 2001
R CLASS		13.96%	0.23%		4.76%	Aug. 29, 2003
S&P 500® Index (reflects no deduction for fees, expenses or taxes)		16.00%	1.66%	7.10%

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

NT CORE EQUITY PLUS FUND

NT CORE EQUITY PLUS FUND

Investment Objective

The fund seeks long-term capital growth.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	NT CORE EQUITY PLUS FUND INSTITUTIONAL CLASS
Management Fee	1.10%
Distribution and Service (12b-1) Fees	none
Dividends on Short Sales	0.31%
Broker Fees and Charges on Short Sales	0.25%
Other	none
Other Expenses	0.56%
Total Annual Fund Operating Expenses	1.66%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn 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 (USD $)	1 year	3 years	5 years	10 years
NT CORE EQUITY PLUS FUND INSTITUTIONAL CLASS	169	524	903	1,964

Portfolio Turnover

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 111% of the average value of its portfolio.

Principal Investments Strategies

The managers use quantitative models to construct the portfolio of equity securities for the fund. The fund invests approximately 130% of its assets in long positions, while 30% of its assets are sold short. A long position arises when the fund buys a security outright. A short position arises when the fund sells a security it does not own but has borrowed in anticipation that the market price of the security will decline. If the market price in fact declines, the fund can replace the borrowed security at a lower price and capture the value represented by the difference between the higher sale price and the lower replacement price. The proceeds from the securities sold short are used to purchase an additional 30% of long positions. The net investment exposure for the fund is a 100% long market exposure.

The portfolio managers buy, or take long positions in, equity securities that they have identified as the most attractive and take short positions in equity securities that they have identified as the least attractive using a multi-factor quantitative model in a two-step process. In the first step, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from the most attractive to least attractive based on an objective set of measures, including a stock’s value, quality, growth, and momentum. In the second step, the managers use a quantitative model to build a portfolio that provides the optimal balance between risk and expected return.

The portfolio managers generally sell a stock from the fund's long portfolio when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

The fund’s use of short selling as a primary investment strategy creates leverage in an attempt to increase returns.

The fund is not permitted to invest in securities issued by companies assigned the Global Industry Classification Standard (GICS) for the tobacco industry.

Principal Risks

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Short Sales Risk - If the market price of a security increases after the fund borrows the security, the fund may suffer a loss when it replaces the borrowed security at the higher price. Any loss will be increased by the amount of compensation, interest or dividends, and transaction costs the fund must pay to the lender of the borrowed security.

• Leverage Risk - The fund’s investment strategy utilizes leverage, which can increase market exposure and subject the fund to greater risk and higher volatility.

• Overweighting Risk - If the fund is overweighted in a stock or sector, any negative development related to that stock or sector will have a greater impact on the fund than other funds that are not overweighted in that stock or sector.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the S&P 500^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Tobacco Exclusion - The fund’s prohibition on tobacco-related investments may cause it to forego profitable investment opportunities.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Calendar Year Total Returns

Highest Performance Quarter (1Q 2012): 13.33%

Lowest Performance Quarter (2Q 2012): -3.86% 

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was 21.98%.

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns NT CORE EQUITY PLUS FUND	1 year	Since Inception	Inception Date
INSTITUTIONAL CLASS	16.49%	15.68%	Dec. 01, 2011
INSTITUTIONAL CLASS Return After Taxes on Distributions	16.05%	15.27%	Dec. 01, 2011
INSTITUTIONAL CLASS Return After Taxes on Distributions and Sale of Fund Shares	11.18%	13.29%	Dec. 01, 2011
S&P 500® Index (reflects no deduction for fees, expenses or taxes)	16.00%	15.96%	Dec. 01, 2011

The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

NT EQUITY GROWTH FUND

NT EQUITY GROWTH FUND

Investment Objective

The fund seeks long-term capital growth.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	NT EQUITY GROWTH FUND INSTITUTIONAL CLASS
Management Fee	0.47%
Distribution and Service (12b-1) Fees	none
Other Expenses	0.01%
Total Annual Fund Operating Expenses	0.48%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn 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 (USD $)	1 year	3 years	5 years	10 years
NT EQUITY GROWTH FUND INSTITUTIONAL CLASS	49	154	269	604

Portfolio Turnover

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 95% of the average value of its portfolio.

Principal Investment Strategies

In selecting stocks for the fund, the portfolio managers use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily large capitalization, publicly traded U.S. companies with a market capitalization greater than $2 billion, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

Under normal market conditions, at least 80% of the fund’s net assets will be invested in equity securities.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

The fund is not permitted to invest in securities issued by companies assigned the Global Industry Classification Standard (GICS) for the tobacco industry.

Principal Risks

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the S&P 500^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Tobacco Exclusion - The fund’s prohibition on tobacco-related investments may cause it to forego profitable investment opportunities.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Institutional Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Calendar Year Total Returns

Highest Performance Quarter (3Q 2009): 14.93%

Lowest Performance Quarter (4Q 2008): -21.29%

As of September 30, 2013, the most recent calendar quarter end, the fund’s Institutional Class year-to-date return was 19.97%.

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns NT EQUITY GROWTH FUND	1 year	5 years	Since Inception	Inception Date
INSTITUTIONAL CLASS	16.28%	1.92%	3.38%	May 12, 2006
INSTITUTIONAL CLASS Return After Taxes on Distributions	15.13%	1.41%	2.92%	May 12, 2006
INSTITUTIONAL CLASS Return After Taxes on Distributions and Sale of Fund Shares	12.10%	1.59%	2.85%	May 12, 2006
S&P 500® Index (reflects no deduction for fees, expenses or taxes)	16.00%	1.66%	3.71%	May 12, 2006

The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

NT SMALL COMPANY FUND

NT SMALL COMPANY FUND

Investment Objective

The fund seeks long-term capital growth.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy and hold shares of the fund.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	NT SMALL COMPANY FUND INSTITUTIONAL CLASS
Management Fee	0.67%
Distribution and Service (12b-1) Fees	none
Other Expenses	0.01%
Total Annual Fund Operating Expenses	0.68%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn 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 (USD $)	1 year	3 years	5 years	10 years
NT SMALL COMPANY FUND INSTITUTIONAL CLASS	70	218	379	847

Portfolio Turnover

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 106% of the average value of its portfolio.

Principal Investment Strategies

Under normal market conditions, the fund will invest at least 80% of its net assets in stocks of smaller-capitalization U.S. companies. The managers consider small companies to be those that, at the time of investment, have a market capitalization not greater than that of the largest company in the Russell 2000^® Index. The portfolio managers use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily smaller U.S. companies, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

The fund is not permitted to invest in securities issued by companies assigned the Global Industry Classification Standard (GICS) for the tobacco industry.

Principal Risks

• Small Cap Stocks - The smaller companies in which the fund invests may be more volatile and subject to greater risk than larger companies. Smaller companies may have limited financial resources, product lines and markets, and their securities may trade less frequently and in more limited volumes than the securities of larger companies, which could lead to higher transaction costs.

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the Russell 2000^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.  

• Tobacco Exclusion - The fund’s prohibition on tobacco-related investments may cause it to forego profitable investment opportunities.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Institutional Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Calendar Year Total Returns

Highest Performance Quarter (3Q 2009): 17.06%

Lowest Performance Quarter (4Q 2008): -26.99% 

As of September 30, 2013, the most recent calendar quarter end, the fund's Institutional Class year-to-date return was 30.11%.

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns NT SMALL COMPANY FUND	1 year	5 years	Since Inception	Inception Date
INSTITUTIONAL CLASS	13.98%	1.37%	(0.15%)	May 12, 2006
INSTITUTIONAL CLASS Return After Taxes on Distributions	12.97%	0.88%	(0.53%)	May 12, 2006
INSTITUTIONAL CLASS Return After Taxes on Distributions and Sale of Fund Shares	10.39%	1.12%	(0.16%)	May 12, 2006
Russell 2000® Index (reflects no deduction for fees, expenses or taxes)	16.35%	3.55%	3.47%	May 12, 2006

The after-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

STRATEGIC INFLATION OPPORTUNITIES FUND

STRATEGIC INFLATION OPPORTUNITIES FUND

Investment Objective

The fund seeks total real return.

Fees and Expenses

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 17 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees STRATEGIC INFLATION OPPORTUNITIES FUND (USD $)	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS		C CLASS	R CLASS
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none	none	5.75%		none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the original offering price or redemption proceeds when redeemed within one year of purchase)	none	none	none	[1]	1.00%	none
Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)	25	none	none		none	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses STRATEGIC INFLATION OPPORTUNITIES FUND		INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS	C CLASS	R CLASS
Management Fee		1.08%	0.88%	1.08%	1.08%	1.08%
Distribution and Service (12b-1) Fees		none	none	0.25%	1.00%	0.50%
Other Expenses		0.01%	0.01%	0.01%	0.01%	0.01%
Acquired Fund Fees and Expenses		0.11%	0.11%	0.11%	0.11%	0.11%
Total Annual Fund Operating Expenses		1.20%	1.00%	1.45%	2.20%	1.70%
Fee Waiver	[1]	0.20%	0.20%	0.20%	0.20%	0.20%
Total Annual Fund Operating Expenses After Waiver		1.00%	0.80%	1.25%	2.00%	1.50%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn 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 STRATEGIC INFLATION OPPORTUNITIES FUND (USD $)	1 year	3 years	5 years	10 years
INVESTOR CLASS	102	362	641	1,436
INSTITUTIONAL CLASS	82	299	534	1,207
A CLASS	695	989	1,304	2,193
C CLASS	203	670	1,162	2,515
R CLASS	153	517	905	1,990

Portfolio Turnover

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 85% of the average value of its portfolio.

Principal Investment Strategies

The fund’s asset allocation strategy seeks to diversify its investments among U.S. Treasury inflation-indexed securities, non-U.S. dollar investments, commodity-related investments, companies engaged in the real estate industry (including securities issued by real estate investment trusts (REITs)), and securities that reflect the price of gold bullion, all in an effort to provide investors total real return. Total real return is total return reduced by the expected impact of inflation. The fund’s investment strategy has been designed in an effort to protect the fund’s investors from the effects of rising U.S. inflation. Generally, the portfolio managers intend to diversify the fund’s investments as indicated in the following table. The table indicates the fund’s neutral mix, that is, how the fund’s investments generally will be allocated among its major asset classes over the long term, and the ranges within which the portfolio managers may make tactical allocations as a result of changing economic conditions or the portfolio managers’ inflation expectations. The portfolio managers will regularly review the fund’s asset mix and adjust the allocation among asset classes as necessary to provide the fund what they believe is the most favorable outlook for achieving the fund’s objective. By adjusting the allocation among asset classes the portfolio managers can moderate risks associated with each asset category.

	U.S. Inflation-Indexed and other U.S. Fixed-Income Securities	Non-U.S. Dollar Investments	Commodity-Related Investments	Real Estate-Related Securities	Gold Securities
Neutral Mix	45%	25%	15%	10%	5%
Operating Ranges	25-65%	15-35%	5-25%	0-20%	0-10%

To help protect against U.S. inflation, the fund will invest a portion of its assets in inflation-indexed debt securities. These securities include inflation-indexed U.S. Treasury securities, inflation-indexed securities issued by U.S. government agencies and instrumentalities other than the U.S. Treasury, and inflation-indexed securities issued by other entities such as corporations. Inflation-indexed securities are designed to protect the future purchasing power of the money invested in them.

The portfolio managers may also purchase U.S. Treasury securities, U.S. Treasury futures, and other U.S. fixed-income securities that are not linked to inflation whether issued by the U.S. government, its agencies or instrumentalities, municipalities, corporations or other non-governmental issuers. A portion of these investments may be in high-yield securities. The fund also may invest in derivative instruments such as options, futures contracts, options on futures contracts, and swap agreements (including, but not limited to, credit default swap agreements), or in mortgage- or asset-backed securities, provided that such instruments are in keeping with the fund’s investment objective.

The fund also will invest a portion of its assets in debt securities of foreign issuers, including issuers located in emerging markets. In managing the fund’s non-U.S. dollar investments, the fund will buy and sell foreign currencies regularly, either in the spot (i.e., cash) market or with foreign currency forward contracts.

Foreign currency forward contracts are agreements to exchange a specific amount of one currency for a specified amount of another at a future date. The date may be any agreed fixed number of days in the future. The amount of currency to be exchanged, the price at which the exchange will take place, and the date of the exchange are negotiated when the fund enters into the contract and are fixed for the term of the contract. Forward contracts are traded in an interbank market conducted directly between currency traders (usually large commercial banks) and their customers. A forward contract generally has no deposit requirement and is consummated without payment of any commission. However, the fund may enter into forward contracts with deposit requirements or commissions.

The fund may also invest in high-quality non-dollar-denominated foreign government and foreign corporate debt securities, as well as inflation-indexed securities issued by foreign governments and corporations. When the managers believe it is prudent, the fund may also invest a portion of the assets from this portion in equity securities of foreign companies, including issuers located in emerging markets. Within this non-U.S. dollar portion, the fund may also invest in short-term securities, including money markets, securities issued or guaranteed by the U.S. government and its agencies and instrumentalities, and commercial paper and other U.S. dollar debt investments.

The fund also will invest a portion of its assets in commodity-related investments. Commodities are assets that have tangible properties, such as oil, metals and agricultural products. Under normal market conditions, the fund’s commodity-related investments will be allocated between equity securities of U.S. and foreign companies engaged in commodity-related businesses and investments that provide investment exposure to underlying investible commodities. Investments in equity securities of foreign companies engaged in commodity-related businesses do not apply to the fund’s neutral mix or operating range for non-U.S. dollar investments. To achieve exposure to underlying commodities, the fund may invest in commodity-linked notes, commodity-related exchange traded notes (ETNs), and exchange traded funds (ETFs) or other pooled investment funds that invest in underlying commodities or that seek to track the performance of a commodity or resource index.

The fund will also invest a portion of its assets in real estate investment trusts (REITs), REIT ETFs and equity securities issued by companies engaged in the real estate industry. A company is considered a real estate company if, in the opinion of the portfolio managers, at least 50% of its revenues or 50% of the market value of its assets at the time the securities are purchased by the fund are attributed to the ownership, construction, management or sale of real estate.

The fund will also invest a portion of its assets in securities that reflect the performance of the price of gold bullion, including through exchange traded funds (ETFs) or other pooled investment funds that invest in underlying gold.

Principal Risks

• Style Risk - If at any time the market is not favoring the fund’s investment style, which is designed for high and rising inflationary cycles, the fund’s gains may not be as big as, or its losses may be bigger than, those of other funds using different investment styles.

• Nondiversification - The fund is classified as nondiversified. A nondiversified fund may invest a greater percentage of its assets in a smaller number of securities than a diversified fund. This gives the managers the flexibility to hold large positions in a small number of securities. If so, a price change in any one of those securities may have a greater impact on the fund’s share price than would be the case for a diversified fund.

• Real Interest Rate Risk - Inflation-indexed securities trade at prevailing real, or after-inflation, interest rates. Changes in real interest rates affect the value of such securities. Generally, when real interest rates rise, the value of the fund’s fixed-income securities will decline. The opposite is true when real interest rates decline.

• Credit Risk - The value of the fund’s fixed-income securities will be affected adversely by any erosion, or perceived erosion, in the ability of the issuers of these securities to make interest and principal payments as they become due.

• Foreign Securities Risk - The fund invests in foreign securities, which are generally riskier than U.S. securities. As a result, the fund is subject to foreign risk, meaning that political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), and natural disasters occurring in a country where the fund invests could cause the fund’s investments in that country to experience gains or losses. Because of these risks, and others, securities of foreign issuers may be less liquid, more volatile, and harder to value than U.S. securities.

• Currency Risk - The fund is subject to the risk of a decline in the value of a foreign currency versus the U.S. dollar, which reduces the dollar value of securities denominated in that currency. The overall impact on the fund’s holdings may be significant depending on the currencies represented in the portfolio, how each one appreciates or depreciates in relation to the U.S. dollar, and whether currency positions are hedged. Currency trends can be volatile, and to the extent the fund purchases and sells currencies, it will also be subject to the risk that its trading strategies, including efforts at hedging, will not succeed.

• Commodity and Gold Investing Risk - The fund’s commodity- and gold-related investments may be subject to greater volatility than investments in traditional securities. The value of the fund’s commodity- and gold-related investments may be affected by changes in overall market movements, interest rate changes, and volatility in commodity- and gold-related indexes. The value of these investments may also be affected by factors affecting a particular commodity, such as weather, disease, embargoes, tariffs, taxes and economic, political and regulatory developments.

• Real Estate Investing - An investment in the fund may be subject to many of the same risks as a direct investment in real estate. These risks include changes in economic conditions, interest rates, property values, property tax increases, overbuilding and increased competition, environmental contamination, zoning and natural disasters. This is due to the fact that the value of the fund’s investments may be affected by the value of the real estate owned by the companies in which it invests.

• Emerging Market Risk - Investing in securities of companies located in emerging market countries generally is also riskier than investing in securities of companies located in foreign developed countries. Emerging market countries may have unstable governments and/or economies that are subject to sudden change. These changes may be magnified by the countries’ emergent financial markets, resulting in significant volatility to investments in these countries.

• Derivative Risk - The use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional instruments. Derivatives are subject to a number of risks, including liquidity, interest rate, market, credit and correlation risk.

• Liquidity Risk - The fund may also be subject to liquidity risk. During periods of market turbulence or unusually low trading activity, in order to meet redemptions it may be necessary for the fund to sell securities at prices that could have an adverse effect on the fund’s share price.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, including yields, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

Highest Performance Quarter (3Q 2012): 4.40%

Lowest Performance Quarter(3Q 2011): -7.83%

As of September 30, 2013, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was -2.67%.

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns STRATEGIC INFLATION OPPORTUNITIES FUND	1 year	Since Inception	Inception Date
INVESTOR CLASS	3.59%	2.35%	Apr. 30, 2010
INVESTOR CLASS Return After Taxes on Distributions	3.59%	2.04%	Apr. 30, 2010
INVESTOR CLASS Return After Taxes on Distributions and Sale of Fund Shares	2.34%	1.83%	Apr. 30, 2010
INSTITUTIONAL CLASS	3.85%	2.55%	Apr. 30, 2010
A CLASS	(2.54%)	(0.13%)	Apr. 30, 2010
C CLASS	2.50%	1.30%	Apr. 30, 2010
R CLASS	3.10%	1.82%	Apr. 30, 2010
Barclays U.S. 1-3 Month Treasury Bill Index (reflects no deduction for fees, expenses or taxes)	0.08%	0.09%	Apr. 30, 2010

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

SMALL COMPANY FUND

SMALL COMPANY FUND

Investment Objective

The fund seeks long-term capital growth by investing primarily in stocks of small companies.

Fees and Expenses

The following table describes the fees and expenses 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 American Century Investments funds. More information about these and other discounts is available from your financial professional and in Calculation of Sales Charges on page 12 of the fund’s prospectus and Sales Charges in Appendix B of the statement of additional information.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees SMALL COMPANY FUND (USD $)	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS		C CLASS	R CLASS
Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)	none	none	5.75%		none	none
Maximum Deferred Sales Charge (Load) (as a percentage of the lower of the original offering price or redemption proceeds when redeemed within one year of purchase)	none	none	none	[1]	1.00%	none
Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)	25	none	none		none	none

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses SMALL COMPANY FUND	INVESTOR CLASS	INSTITUTIONAL CLASS	A CLASS	C CLASS	R CLASS
Management Fee	0.87%	0.67%	0.87%	0.87%	0.87%
Distribution and Service (12b-1) Fees	none	none	0.25%	1.00%	0.50%
Other Expenses	0.01%	0.01%	0.01%	0.01%	0.01%
Total Annual Fund Operating Expenses	0.88%	0.68%	1.13%	1.88%	1.38%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn 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 SMALL COMPANY FUND (USD $)	1 year	3 years	5 years	10 years
INVESTOR CLASS	90	281	488	1,085
INSTITUTIONAL CLASS	70	218	379	847
A CLASS	684	914	1,162	1,870
C CLASS	191	592	1,017	2,198
R CLASS	141	438	756	1,656

Portfolio Turnover

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 93% of the average value of its portfolio.

Principal Investment Strategies

Under normal market conditions, the fund will invest at least 80% of its net assets in stocks of smaller-capitalization U.S. companies. The portfolio managers consider small companies to be those that, at the time of investment, have a market capitalization not greater than that of the largest company in the Russell 2000^® Index. The portfolio managers use quantitative management techniques in a two-step process. First, the managers rank stocks, primarily smaller U.S. companies, from most attractive to least attractive based on an objective set of measures, including each stock’s value, quality, growth, and momentum. Second, the portfolio managers use a quantitative model to build a portfolio of stocks from the ranking described above that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Principal Risks

• Small Cap Stocks - The smaller companies in which the fund invests may be more volatile and subject to greater risk than larger companies. Smaller companies may have limited financial resources, product lines and markets, and their securities may trade less frequently and in more limited volumes than the securities of larger companies, which could lead to higher transaction costs.

• Style Risk - If at any time the market is not favoring the fund’s quantitative investment style, the fund’s gains may not be as big as, or its losses may be bigger than, those of other equity funds using different investment styles.

• Investment Process Risk - Stocks selected by the portfolio managers using quantitative models may perform differently than expected due to the portfolio managers' judgments regarding the factors used in the models, the weight placed on each factor, changes from the factors' historical trends, and technical issues with the construction and implementation of the models (including, for example, data problems and/or software or other implementation issues). There is no guarantee that the use of the quantitative model will result in effective investment decisions for the fund. Additionally, the commonality of portfolio holdings across quantitative investment managers may amplify losses.

• Benchmark Correlation - The fund’s performance will be tied to the performance of its benchmark, the Russell 2000^® Index. If the fund’s benchmark goes down, it is likely that the fund’s performance will go down.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

Highest Performance Quarter (2Q 2003): 22.31%

Lowest Performance Quarter (4Q 2008): -26.86%

As of September 30, 2013, the most recent calendar quarter end, the fund's Investor Class year-to-date return was 29.93%.

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns SMALL COMPANY FUND		1 year	5 years		10 years		Since Inception	Inception Date
INVESTOR CLASS		13.92%	1.37%		8.49%			Jul. 31, 1998
INVESTOR CLASS Return After Taxes on Distributions		13.73%	1.31%		7.74%			Jul. 31, 1998
INVESTOR CLASS Return After Taxes on Distributions and Sale of Fund Shares		9.30%	1.16%		7.30%			Jul. 31, 1998
INSTITUTIONAL CLASS		14.00%	1.56%		8.69%			Oct. 01, 1999
A CLASS	[1]	7.07%	(0.08%)		7.58%			Sep. 07, 2000
C CLASS		12.85%	0.36%	[2]	7.41%	[2]		Mar. 01, 2010
R CLASS		13.24%	0.86%				5.64%	Aug. 29, 2003
Russell 2000® Index (reflects no deduction for fees, expenses or taxes)		16.35%	3.56%		9.72%

The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

UTILITIES FUND

UTILITIES FUND

Investment Objective

The fund seeks current income and long-term growth of capital and income. The fund invests at least 80% of its assets in equity securities of companies engaged in the utilities industry.

Fees and Expenses

The following table describes the fees and expenses you may pay if you buy and hold shares of the fund.

Shareholder Fees (fees paid directly from your investment)

Shareholder Fees (USD $)	UTILITIES FUND INVESTOR CLASS
Maximum Annual Account Maintenance Fee (waived if eligible investments total at least $10,000)	25

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)

Annual Fund Operating Expenses	UTILITIES FUND INVESTOR CLASS
Management Fee	0.67%
Distribution and Service (12b-1) Fees	none
Other Expenses	0.01%
Total Annual Fund Operating Expenses	0.68%

Example

The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds.

The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn 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 (USD $)	1 year	3 years	5 years	10 years
UTILITIES FUND INVESTOR CLASS	70	218	379	847

Portfolio Turnover

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 41% of the average value of its portfolio.

Principal Investment Strategies

Under normal market conditions, the fund invests at least 80% of its net assets in equity securities of companies engaged in the utilities industry. The managers consider a company to be engaged in the utilities industry if

• the company’s securities are listed in at least one index that is made up exclusively of companies engaged in one or more of the following industries: electricity, natural gas, telecommunications services, cable television, water or sanitation services; or

• the company derives 50% or more of its revenues or net profits from the ownership or operation of facilities used to provide electricity, natural gas, telecommunications services, cable television, water or sanitation services.

The portfolio managers use quantitative and qualitative management techniques as well as risk controls to construct the fund’s portfolio. The quantitative process involves ranking stocks based on their growth and valuation characteristics. This ranking may be modified by the portfolio managers after they evaluate qualitative factors such as regulatory environment, industry conditions and company specific events. Finally, the managers use a quantitative model to build a portfolio of stocks that they believe will provide the optimal balance between risk and expected return.

The portfolio managers generally sell a stock when they believe it has become less attractive relative to other opportunities, its risk characteristics outweigh its return opportunity or specific events alter its prospects.

Principal Risks

• Concentration Risk - The fund concentrates its investments in the utilities industry, which at times may be limited to a relatively small number of securities. Therefore, the fund may be subject to greater risks and market fluctuations than a portfolio representing a broader range of industries. The performance of the utilities industry will depend in part on investor perception of the sector relative to other sectors. Companies in the utilities industry are subject to various industry-specific risks.

• Foreign Securities Risk - The fund may invest in foreign securities, which may be riskier than investing in U.S. securities. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.

• Market Risk - The value of the fund’s shares will go up and down based on the performance of the companies whose securities it owns and other factors generally affecting the securities market.

• Price Volatility - The value of the fund’s shares may fluctuate significantly in the short term.

• Principal Loss - At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.

An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.

Fund Performance

The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, please visit americancentury.com.

Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.

Calendar Year Total Returns

Highest Performance Quarter (2Q 2003): 17.77%

Lowest Performance Quarter (3Q 2008): -17.27%

As of September 30, 2013, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 13.28%.

Average Annual Total Returns For the calendar year ended December 31, 2012

Average Annual Total Returns UTILITIES FUND	1 year	5 years	10 years
INVESTOR CLASS	4.26%	0.30%	10.11%
INVESTOR CLASS Return After Taxes on Distributions	2.82%	(0.41%)	9.50%
INVESTOR CLASS Return After Taxes on Distributions and Sale of Fund Shares	4.71%	0.20%	8.93%
S&P 500® Index (reflects no deduction for fees, expenses or taxes)	16.00%	1.66%	7.10%
Russell 3000 Utilities Index (reflects no deduction for fees, expenses or taxes)	7.67%	1.47%	8.32%

After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.

[1] Investments of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of the purchase.

[1] Investments of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of the purchase.

[1] Investments of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of the purchase.

[1] Prior to September 4, 2007, this class was referred to as the Advisor Class and did not have a front-end sales charge. Performance has been restated to reflect this charge.

[1] Investments of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of the purchase.

[1] Other Expenses are based on estimated amounts for the current fiscal year.

[2] The advisor has agreed to waive 0.07 percentage points of the fund's management fee. The advisor expects this waiver to continue for one year from the date of this prospectus, and cannot terminate it prior to such date without the approval of the Board of Directors.

[1] Investments of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of the purchase.

[1] Investments of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of the purchase.

[1] Prior to September 4, 2007, this class was referred to as the Advisor Class and did not have a front-end sales charge. Performance has been restated to reflect this charge.

[1] Investments of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of the purchase.

[1] Prior to September 4, 2007, this class was referred to as the Advisor Class and did not have a front-end sales charge. Performance has been restated to reflect this charge.

[2] NYSE Arca Gold Miners Index benchmark total return data is first available as of October 1, 2004.

[1] Investments of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of the purchase.

[1] Investments of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of the purchase.

[1] Prior to September 4, 2007, this class was referred to as the Advisor Class and did not have a front-end sales charge. Performance has been restated to reflect this charge.

[1] Investments of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of the purchase.

[1] The advisor has agreed to waive 0.20 percentage points of the fund's management fee. The advisor expects this waiver to continue until October 31, 2014, and cannot terminate it prior to such date without the approval of the Board of Directors.

[1] Investments of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of the purchase.

[1] Prior to March 1, 2010, the A Class was referred to as the Advisor Class and did not have a front-end sales charge. Performance prior to that date has been restated to reflect this charge.

[2] Historical performance for C Class prior to its inception is based on the performance of Investor Class shares. C Class performance has been adjusted to reflect differences in sales charges, if applicable, and expenses between classes.