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Label Element Value
Prospectus: rr_ProspectusTable  
Document Type dei_DocumentType 485BPOS
Document Period End Date dei_DocumentPeriodEndDate Mar. 31, 2020
Entity Registrant Name dei_EntityRegistrantName AMERICAN CENTURY INVESTMENT TRUST
Central Index Key dei_EntityCentralIndexKey 0000908406
Amendment Flag dei_AmendmentFlag false
Document Creation Date dei_DocumentCreationDate Jul. 29, 2020
Document Effective Date dei_DocumentEffectiveDate Aug. 01, 2020
Prospectus Date rr_ProspectusDate Aug. 01, 2020
Investment Trust Prospectus | CORE PLUS FUND  
Prospectus: rr_ProspectusTable  
Risk/Return [Heading] rr_RiskReturnHeading Core Plus Fund
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The fund seeks to maximize total return.
Objective, Secondary [Text Block] rr_ObjectiveSecondaryTextBlock
As a secondary objective, the fund seeks a high level of income.
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, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 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 15 of the fund’s prospectus, Appendix A 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 129% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 129.00%
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 $100,000 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 15 of the fund’s prospectus, Appendix A 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 $ 100,000
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 and that you earn a 5% return each year. The example also assumes that the fund’s operating expenses remain the same, except that it reflects the rate and duration of any fee waivers noted in the table above. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading] rr_StrategyHeading Principal Investment Strategies
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock
The fund invests at least 65% of its assets in investment-grade, non-money market debt securities. An investment-grade security is one that has been rated by a nationally recognized statistical rating organization in its top four credit quality categories or determined by the advisor to be of comparable credit quality. Debt securities include fixed-income investments such as notes, bonds, commercial paper and U.S. Treasury securities. These securities, which may be payable in U.S. or foreign currencies, may include corporate bonds and notes, government securities and securities backed by mortgages or other assets.
The fund may invest in high-yield debt securities. A high-yield security, or junk bond, is one that has been rated below the four highest categories used by a nationally recognized statistical rating organization, or determined by the investment advisor to be of similar quality. The fund may also invest in securities issued by companies that are located in emerging market countries—emerging market securities. The fund may not invest more than 35% of its assets in high-yield securities.
The fund may invest in non-dollar denominated debt securities. The weighted average maturity of the fund’s portfolio must be 3½ years or longer.
The fund may invest in securities issued or guaranteed by the U.S. Treasury and certain U.S. government agencies or instrumentalities such as the Government National Mortgage Association (Ginnie Mae). Ginnie Mae is supported by the full faith and credit of the U.S. government. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank (FHLB) are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, they are authorized to borrow from the U.S. Treasury to meet their obligations.
In addition to the debt securities described above, the fund may also invest in bank loans.
The fund also may invest in derivative instruments provided that such investments are in keeping with the fund’s investment objectives. Such derivative instruments may include options, futures contracts, options on futures contracts, and swaps (including credit default swaps). The fund may invest in collateralized debt obligations, including collateralized loan obligations, collateralized mortgage obligations, mortgage- or asset- backed securities, and other similarly structured investments. The fund may use foreign currency exchange contracts to shift investment exposure from one currency into another for hedging purposes or to enhance returns.
To determine whether to buy or sell a security, the portfolio managers consider, among other things, various fund requirements and standards, along with economic conditions, alternative investments and interest rates.
To gain exposure to certain segments of the fixed-income market, the fund may invest in other American Century funds (affiliated funds).
The fund may engage in active and frequent trading of portfolio securities to achieve its principal investment strategies. This may cause higher transaction costs and may affect performance. It may also result in the realization and distribution of capital gains.
Risk [Heading] rr_RiskHeading Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock
•
Interest Rate Risk – Investments in debt securities are sensitive to interest rate changes. Generally, the value of debt securities and the funds that hold them decline as interest rates rise. This fund is more susceptible to interest rate changes than funds that have a shorter-weighted average maturity, such as money market and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.
•
Credit Risk – The inability or perceived inability of a security’s issuer to make interest and principal payments may cause the value of the security to decrease. As a result the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect.
•
High-Yield Risk – Issuers of high-yield securities are more vulnerable to real or perceived economic changes (such as an economic downturn or a prolonged period of rising interest rates), political changes or adverse developments specific to an issuer. These factors may be more likely to cause an issuer of low quality bonds to default on its obligations.
•
Liquidity Risk – During periods of market turbulence or unusually low trading activity, 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 price. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments.
•
Prepayment Risk – The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds of similar maturity that invest less heavily in mortgage- and asset-backed securities.
•
LIBOR Transition Risk – The fund may invest in instruments that have variable or floating coupon rates based on the London Interbank Offered Rate (“LIBOR”). LIBOR is a benchmark interest rate intended to be representative of the rate at which certain major international banks lend to one another over short-terms. Due to allegations of manipulation, LIBOR will be phased out by the end of 2021. Uncertainty remains regarding a replacement rate or rates for LIBOR. The transition process may lead to increased volatility or illiquidity in markets for instruments that rely on LIBOR. This could result in a change to the value of such instruments or a change in the cost of temporary borrowing for the fund.
•
Foreign Securities Risk – Foreign securities are generally riskier than U.S. securities. Political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), natural disasters and public health emergencies occurring in a country where the fund invests could cause the fund’s investments in that country to experience losses. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.
•
Currency Risk – Because the fund may invest in securities denominated in foreign currencies, the fund could experience gains or losses based solely on changes in the exchange rate between foreign currencies and the U.S. dollar.
•
Emerging Market Risk – Investing in emerging market countries generally is also riskier than investing in foreign developed countries. Emerging market countries may have unstable governments and/or economies that are subject to sudden change, and significant volatility in their financial markets. These countries also may lack the legal, business and social framework to support securities markets.
•
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.
•
Bank Loan Risk – The market for bank loans may not be highly liquid and the fund may have difficulty selling them. In connection with purchasing loan participations, the fund generally will have no right to enforce compliance by borrowers with loan terms nor any set off rights, and the fund may not benefit directly from any posted collateral. As a result, the fund may be subject to the credit risk of both the borrower and the lender selling the participation. Bank loan transactions may take more than seven days to settle, meaning that proceeds would be unavailable to make additional investments or meet redemptions.
•
Collateralized Debt Obligations Risk – Collateralized debt obligations and collateralized loan obligations (CLOs) are subject to credit, interest rate, valuation, and prepayment and extension risks. These securities also are subject to risk of default on the underlying asset, particularly during periods of economic downturn. The market value of CLOs may be affected by, among other things, changes in the market value of the underlying assets held by the CLO, changes in the distributions on the underlying assets, defaults and recoveries on the underlying assets, capital gains and losses on the underlying assets, prepayments on underlying assets and the availability, prices and interest rate of underlying assets.
•
Market Risk – The value of securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.
•
Redemption Risk – The fund may need to sell securities at times it would not otherwise do so in order to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.
•
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. Because the G Class does not have investment performance for a full calendar year, it is not included. 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 (1Q 2019): 3.62% Lowest Performance Quarter (2Q 2013): -2.88%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 3.98%.
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns For the calendar year ended December 31, 2019
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.
Investment Trust Prospectus | CORE PLUS FUND | Bloomberg Barclays U.S Aggregate Bond Index  
Prospectus: rr_ProspectusTable  
Index No Deduction for Fees, Expenses, Taxes [Text] rr_IndexNoDeductionForFeesExpensesTaxes (reflects no deduction for fees, expenses or taxes)
Label rr_AverageAnnualReturnLabel Bloomberg Barclays U.S. Aggregate Bond Index    (reflects no deduction for fees, expenses or taxes)
1 Year rr_AverageAnnualReturnYear01 8.72%
5 Years rr_AverageAnnualReturnYear05 3.05%
10 Years rr_AverageAnnualReturnYear10 3.74%
Investment Trust Prospectus | CORE PLUS FUND | INVESTOR CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACCNX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee $ 25
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.54% [1]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.56%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.56%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 57
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 180
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 313
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 702
Annual Return 2010 rr_AnnualReturn2010 6.79%
Annual Return 2011 rr_AnnualReturn2011 7.47%
Annual Return 2012 rr_AnnualReturn2012 5.75%
Annual Return 2013 rr_AnnualReturn2013 (2.58%)
Annual Return 2014 rr_AnnualReturn2014 5.86%
Annual Return 2015 rr_AnnualReturn2015 (0.03%)
Annual Return 2016 rr_AnnualReturn2016 3.56%
Annual Return 2017 rr_AnnualReturn2017 4.57%
Annual Return 2018 rr_AnnualReturn2018 (1.40%)
Annual Return 2019 rr_AnnualReturn2019 9.04%
Year to Date Return, Label rr_YearToDateReturnLabel Investor Class year-to-date return
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2020
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn 3.98%
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Highest Performance Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Mar. 31, 2019
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 3.62%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Lowest Performance Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Jun. 30, 2013
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (2.88%)
Label rr_AverageAnnualReturnLabel Investor Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 9.04%
5 Years rr_AverageAnnualReturnYear05 3.08%
10 Years rr_AverageAnnualReturnYear10 3.83%
Investment Trust Prospectus | CORE PLUS FUND | INVESTOR CLASS | After Taxes on Distributions  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions
1 Year rr_AverageAnnualReturnYear01 7.81%
5 Years rr_AverageAnnualReturnYear05 1.77%
10 Years rr_AverageAnnualReturnYear10 2.48%
Investment Trust Prospectus | CORE PLUS FUND | INVESTOR CLASS | After Taxes on Distributions and Sales  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions and Sale of Fund Shares
1 Year rr_AverageAnnualReturnYear01 5.33%
5 Years rr_AverageAnnualReturnYear05 1.76%
10 Years rr_AverageAnnualReturnYear10 2.40%
Investment Trust Prospectus | CORE PLUS FUND | I CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACCTX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.44% [1]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.46%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.46%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 47
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 148
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 258
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 580
Label rr_AverageAnnualReturnLabel I Class1 Return Before Taxes [2]
1 Year rr_AverageAnnualReturnYear01 9.26% [2]
5 Years rr_AverageAnnualReturnYear05 3.19% [2]
10 Years rr_AverageAnnualReturnYear10 3.93% [2]
Investment Trust Prospectus | CORE PLUS FUND | A CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACCQX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice 4.50%
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none [3]
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.54% [1]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.81%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.81%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 529
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 697
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 880
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,407
Label rr_AverageAnnualReturnLabel A Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 3.91%
5 Years rr_AverageAnnualReturnYear05 1.89%
10 Years rr_AverageAnnualReturnYear10 3.10%
Investment Trust Prospectus | CORE PLUS FUND | C CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACCKX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther 1.00%
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.54% [1]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 1.00%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.56%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 1.56%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 159
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 493
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 851
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,855
Label rr_AverageAnnualReturnLabel C Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 7.96%
5 Years rr_AverageAnnualReturnYear05 2.06%
10 Years rr_AverageAnnualReturnYear10 2.80%
Investment Trust Prospectus | CORE PLUS FUND | R CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACCPX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.54% [1]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.50%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.06%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 1.06%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 108
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 338
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 585
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,294
Label rr_AverageAnnualReturnLabel R Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 8.50%
5 Years rr_AverageAnnualReturnYear05 2.57%
10 Years rr_AverageAnnualReturnYear10 3.32%
Investment Trust Prospectus | CORE PLUS FUND | R5 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACCUX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.34% [1]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.36%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.36%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 37
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 116
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 202
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 26
Label rr_AverageAnnualReturnLabel R5 Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 9.36%
5 Years rr_AverageAnnualReturnYear05 3.29%
10 Years rr_AverageAnnualReturnYear10 4.04%
Investment Trust Prospectus | CORE PLUS FUND | G CLASS  
Prospectus: rr_ProspectusTable  
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.34% [1]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.36%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets (0.34%) [4]
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.02%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 2
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 6
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 11
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 456
Investment Trust Prospectus | DIVERSIFIED BOND FUND  
Prospectus: rr_ProspectusTable  
Risk/Return [Heading] rr_RiskReturnHeading Diversified Bond Fund
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The fund seeks a high level of income by investing in non-money market debt securities.
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, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for A Class sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 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 15 of the fund’s prospectus, Appendix A 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 82% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 82.00%
Expense Breakpoint Discounts [Text] rr_ExpenseBreakpointDiscounts You may qualify for A Class sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 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 15 of the fund’s prospectus, Appendix A 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 $ 100,000
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
Under normal market conditions, the fund invests at least 80% of its net assets in high- and medium-grade, non-money market debt securities. These securities, which may be payable in U.S. or foreign currencies, may include corporate bonds and notes, government securities and securities backed by mortgages or other assets. Shorter-term debt securities round out the portfolio.
The fund invests most of its assets in investment-grade securities. An investment-grade security is one that has been rated by an independent rating agency in its top four credit quality categories or determined by the advisor to be of comparable credit quality. The weighted average maturity of the fund’s portfolio must be three and one-half years or longer.
The fund may invest in securities issued or guaranteed by the U.S. Treasury and certain U.S. government agencies or instrumentalities such as the Government National Mortgage Association (Ginnie Mae). Ginnie Mae is supported by the full faith and credit of the U.S. government. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank (FHLB) are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, they are authorized to borrow from the U.S. Treasury to meet their obligations.
In addition to the debt securities described above, the fund may also invest in bank loans.
The fund also may invest in derivative instruments provided that such investments are in keeping with the fund’s investment objective. Such derivatives may include options, futures contracts, options on futures contracts, and swaps (including credit default swaps). The fund may invest in collateralized debt obligations, including collateralized loan obligations, collateralized mortgage obligations, mortgage- or asset- backed securities, and other similarly structured investments. The fund may use foreign currency exchange contracts to shift investment exposure from one currency into another for hedging purposes.
To determine whether to buy or sell a security, the portfolio managers consider, among other things, various fund requirements and standards, along with economic conditions, alternative investments and interest rates.
The fund may engage in active and frequent trading of portfolio securities to achieve its principal investment strategies. This may cause higher transaction costs and may affect performance. It may also result in the realization and distribution of capital gains.
Risk [Heading] rr_RiskHeading Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock
•
Interest Rate Risk – Investments in debt securities are sensitive to interest rate changes. Generally, the value of debt securities and the funds that hold them decline as interest rates rise. This fund is more susceptible to interest rate changes than funds that have shorter-weighted maturities, such as money market and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.
•
Credit Risk – The inability or perceived inability of a security’s issuer to make interest and principal payments may cause the value of the security to decrease. As a result the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect.
•
Prepayment Risk – The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds of similar maturity that invest less heavily in mortgage- and asset-backed securities.
•
LIBOR Transition Risk – The fund may invest in instruments that have variable or floating coupon rates based on the London Interbank Offered Rate (“LIBOR”). LIBOR is a benchmark interest rate intended to be representative of the rate at which certain major international banks lend to one another over short-terms. Due to allegations of manipulation, LIBOR will be phased out by the end of 2021. Uncertainty remains regarding a replacement rate or rates for LIBOR. The transition process may lead to increased volatility or illiquidity in markets for instruments that rely on LIBOR. This could result in a change to the value of such instruments or a change in the cost of temporary borrowing for the fund.
•
Foreign Securities Risk – Foreign securities are generally riskier than U.S. securities. Political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), natural disasters and public health emergencies occurring in a country where the fund invests could cause the fund’s investments in that country to experience losses. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.
•
Emerging Market Risk – Investing in emerging market countries generally is also riskier than investing in foreign developed countries. Emerging market countries may have unstable governments and/or economies that are subject to sudden change, and significant volatility in their financial markets. These countries also may lack the legal, business and social framework to support securities markets.
•
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.
•
Bank Loan Risk – The market for bank loans may not be highly liquid and the fund may have difficulty selling them. In connection with purchasing loan participations, the fund generally will have no right to enforce compliance by borrowers with loan terms nor any set off rights, and the fund may not benefit directly from any posted collateral. As a result, the fund may be subject to the credit risk of both the borrower and the lender selling the participation. Bank loan transactions may take more than seven days to settle, meaning that proceeds would be unavailable to make additional investments or meet redemptions.
•
Collateralized Debt Obligations Risk – Collateralized debt obligations and collateralized loan obligations (CLOs) are subject to credit, interest rate, valuation, and prepayment and extension risks. These securities also are subject to risk of default on the underlying asset, particularly during periods of economic downturn. The market value of CLOs may be affected by, among other things, changes in the market value of the underlying assets held by the CLO, changes in the distributions on the underlying assets, defaults and recoveries on the underlying assets, capital gains and losses on the underlying assets, prepayments on underlying assets and the availability, prices and interest rate of underlying assets.
•
Liquidity Risk – During periods of market turbulence or unusually low trading activity, 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. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments.
•
Market Risk – The value of securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.
•
Redemption Risk – The fund may need to sell securities at times it would not otherwise do so in order to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.
•
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 I 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 I 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 2011): 3.35% Lowest Performance Quarter (4Q 2016): -2.96%

As of June 30, 2020, the most recent calendar quarter end, the fund’s I Class year-to-date return was 6.02%.
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns For the calendar year ended December 31, 2019
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 I 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 I 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.
Investment Trust Prospectus | DIVERSIFIED BOND FUND | Bloomberg Barclays U.S Aggregate Bond Index  
Prospectus: rr_ProspectusTable  
Index No Deduction for Fees, Expenses, Taxes [Text] rr_IndexNoDeductionForFeesExpensesTaxes  (reflects no deduction for fees, expenses or taxes)
Label rr_AverageAnnualReturnLabel Bloomberg Barclays U.S. Aggregate Bond Index    (reflects no deduction for fees, expenses or taxes)
1 Year rr_AverageAnnualReturnYear01 8.72%
5 Years rr_AverageAnnualReturnYear05 3.05%
10 Years rr_AverageAnnualReturnYear10 3.74%
Investment Trust Prospectus | DIVERSIFIED BOND FUND | INVESTOR CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ADFIX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee $ 25
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.59%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.60%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 61
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 193
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 335
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 751
Label rr_AverageAnnualReturnLabel Investor Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 8.39%
5 Years rr_AverageAnnualReturnYear05 2.54%
10 Years rr_AverageAnnualReturnYear10 3.46%
Inception Date rr_AverageAnnualReturnInceptionDate Dec. 03, 2001
Investment Trust Prospectus | DIVERSIFIED BOND FUND | I CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACBPX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee $ 25
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.39%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.40%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 41
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 129
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 225
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 506
Annual Return 2010 rr_AnnualReturn2010 6.54%
Annual Return 2011 rr_AnnualReturn2011 7.42%
Annual Return 2012 rr_AnnualReturn2012 5.42%
Annual Return 2013 rr_AnnualReturn2013 (2.29%)
Annual Return 2014 rr_AnnualReturn2014 6.23%
Annual Return 2015 rr_AnnualReturn2015 0.41%
Annual Return 2016 rr_AnnualReturn2016 2.72%
Annual Return 2017 rr_AnnualReturn2017 3.54%
Annual Return 2018 rr_AnnualReturn2018 (1.26%)
Annual Return 2019 rr_AnnualReturn2019 8.58%
Year to Date Return, Label rr_YearToDateReturnLabel I Class year-to-date return
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2020
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn 6.02%
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Highest Performance Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Sep. 30, 2011
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 3.35%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Lowest Performance Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2016
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (2.96%)
Label rr_AverageAnnualReturnLabel I Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 8.58%
5 Years rr_AverageAnnualReturnYear05 2.74%
10 Years rr_AverageAnnualReturnYear10 3.67%
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 01, 1993
Investment Trust Prospectus | DIVERSIFIED BOND FUND | I CLASS | After Taxes on Distributions  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions
1 Year rr_AverageAnnualReturnYear01 7.48%
5 Years rr_AverageAnnualReturnYear05 1.61%
10 Years rr_AverageAnnualReturnYear10 2.40%
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 01, 1993
Investment Trust Prospectus | DIVERSIFIED BOND FUND | I CLASS | After Taxes on Distributions and Sales  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions and Sale of Fund Shares
1 Year rr_AverageAnnualReturnYear01 5.07%
5 Years rr_AverageAnnualReturnYear05 1.59%
10 Years rr_AverageAnnualReturnYear10 2.32%
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 01, 1993
Investment Trust Prospectus | DIVERSIFIED BOND FUND | Y CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ADVYX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.36%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.37%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 38
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 119
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 208
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 469
Label rr_AverageAnnualReturnLabel Y Class1 Return Before Taxes [5]
1 Year rr_AverageAnnualReturnYear01 8.61% [5]
5 Years rr_AverageAnnualReturnYear05 2.78% [5]
Since Inception rr_AverageAnnualReturnSinceInception 3.15% [5]
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 10, 2017 [5]
Investment Trust Prospectus | DIVERSIFIED BOND FUND | A CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ADFAX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice 4.50%
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none [6]
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.59%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.85%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 533
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 709
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 901
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,452
Label rr_AverageAnnualReturnLabel A Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 3.26%
5 Years rr_AverageAnnualReturnYear05 1.36%
10 Years rr_AverageAnnualReturnYear10 2.73%
Inception Date rr_AverageAnnualReturnInceptionDate Dec. 03, 2001
Investment Trust Prospectus | DIVERSIFIED BOND FUND | C CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol CDBCX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther 1.00%
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.59%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 1.00%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.60%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 163
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 506
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 872
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,899
Label rr_AverageAnnualReturnLabel C Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 7.34%
5 Years rr_AverageAnnualReturnYear05 1.53%
10 Years rr_AverageAnnualReturnYear10 2.44%
Inception Date rr_AverageAnnualReturnInceptionDate Jan. 31, 2003
Investment Trust Prospectus | DIVERSIFIED BOND FUND | R CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ADVRX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.59%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.50%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.10%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 112
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 350
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 607
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,340
Label rr_AverageAnnualReturnLabel R Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 7.91%
5 Years rr_AverageAnnualReturnYear05 2.04%
10 Years rr_AverageAnnualReturnYear10 2.95%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 29, 2005
Investment Trust Prospectus | DIVERSIFIED BOND FUND | R5 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ADRVX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.39%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.40%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 41
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 129
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 225
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 506
Label rr_AverageAnnualReturnLabel R5 Class2 Return Before Taxes [7]
1 Year rr_AverageAnnualReturnYear01 8.58% [7]
5 Years rr_AverageAnnualReturnYear05 2.75% [7]
10 Years rr_AverageAnnualReturnYear10 3.67% [7]
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 10, 2017 [7]
Investment Trust Prospectus | DIVERSIFIED BOND FUND | R6 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ADDVX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.34%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.35%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 36
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 113
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 197
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 444
Label rr_AverageAnnualReturnLabel R6 Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 8.73%
5 Years rr_AverageAnnualReturnYear05 2.81%
Since Inception rr_AverageAnnualReturnSinceInception 3.19%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 26, 2013
Investment Trust Prospectus | HIGH INCOME FUND  
Prospectus: rr_ProspectusTable  
Risk/Return [Heading] rr_RiskReturnHeading High Income Fund
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The fund seeks current yield and 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, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 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, Appendix A 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 55% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 55.00%
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 $100,000 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, Appendix A 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 $ 100,000
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 invests primarily in high-yield corporate bonds and other debt instruments with an emphasis on those that are rated below investment-grade. A high-yield security, or junk bond, is one that has been rated below the four highest categories used by a nationally recognized statistical rating organization, or, if unrated, determined by the investment advisor to be of similar quality.
Types of high-yield securities the fund may invest in include: bank loans in the form of assignments or participations; payment-in-kind securities; deferred payment securities; and fixed, variable, and floating rate obligations. The fund may invest in new issuances of high yield securities, distressed securities, and restricted or illiquid securities, including Rule 144A securities.
Bank loans include senior secured and unsecured floating rate loans of corporations, partnerships, or other entities. Typically these loans hold a senior position in the borrower’s capital structure, they have interest rates that reset frequently, and they may be secured by the borrower’s assets or they may be unsecured. The fund may invest up to 20% of its net assets in bank loan investments.
Deferred payment securities are zero-coupon securities that convert on a specified date to interest bearing debt securities. On this date, the stated coupon rate becomes effective and interest is paid at regular intervals.
The fund may invest in fixed-income instruments of foreign issuers, including emerging market issuers. Generally, the fund invests in U.S. dollar denominated securities, however, the fund may invest in securities denominated in foreign currencies.
The fund has no average maturity limitations, but it typically invests in intermediate-term and long-term debt securities. The fund may also invest in short-term money market instruments and U.S. government securities.
To determine whether to buy or sell a security, the portfolio managers consider, among other things, various fund requirements and standards, along with economic conditions, alternative investments and interest rates.
Risk [Heading] rr_RiskHeading Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock
•
Credit Risk – The inability or perceived inability of a security’s issuer to make interest and principal payments may cause the value of the security to decrease. As a result, the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect.
•
High-Yield Risk – Issuers of high-yield securities are more vulnerable to real or perceived economic changes (such as an economic down turn or a prolonged period of rising interest rates), political changes or adverse developments specific to an issuer than issuers of investment grade debt securities. High-yield securities (junk bonds) are inherently speculative. These factors may be more likely to cause an issuer of high-yield bonds to default on its obligations.
•
Liquidity Risk – The market for lower-quality debt securities is generally less liquid than the market for higher-quality securities. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments. During periods of market turbulence or unusually low trading activity, 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.
•
Interest Rate Risk – Generally, the value of debt securities and the funds that hold them decline as interest rates rise. Because the fund typically invests in intermediate-term and long-term debt securities, the fund’s interest rate risk is generally higher than for funds with shorter-weighted average maturities, such as money market and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.
•
New Issue Risk – The market value of newly issued securities may fluctuate considerably due to factors such as the absence of a prior public market, unseasoned trading, the limited availability for trading, and limited information about the issuer.
•
Bank Loans Risk – When purchasing participations, the fund generally has no rights to enforce borrower compliance with the terms of the loan agreement, nor any rights of set-off against the borrower, and the fund may not benefit directly from any collateral supporting the loan. This means the fund assumes the credit risk of both the borrower and the lender that sells the participation. Investments in unsecured bank loans are subject to greater risk than investment in loans secured by collateral. Bank loan transactions may take more than seven days to settle, meaning that proceeds would be unavailable to make additional purchases or meet redemptions. Finally, bank loans may not be considered “securities” under the federal securities laws. Therefore, the fund may not be able to rely on the anti-fraud provisions of those laws.
•
Distressed Securities Risk – Distressed securities are speculative and involve substantial risk in addition to the risks of investing in high-yield bonds. Distressed securities frequently do not produce income while they are outstanding and may require the fund to bear certain extraordinary expenses to protect and recover its investment. Distressed securities are at high risk for default and may include securities that have already defaulted. The fund could lose its entire investment.
•
Deferred Payment Securities Risk – During the time that interest payments are not being made on these securities, holders are deemed to receive income (phantom income) annually, even though cash is not received. Additionally, these securities may be subject to greater price fluctuations when interest rates change than securities that currently pay interest. Longer term zero-coupon bonds are more exposed to this risk than those with shorter terms.
•
Foreign Securities Risk – Foreign securities are generally riskier than U.S. securities. Political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), natural disasters and public health emergencies occurring in a country where the fund invests could cause the fund’s investments in that country to experience losses. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.
•
Emerging Market Risk – Investing in emerging market countries generally is also riskier than investing in foreign developed countries. Emerging market countries may have unstable governments and/or economies that are subject to sudden change, and significant volatility in their financial markets. These countries also may lack the legal, business and social framework to support securities markets.
•
Restricted and Illiquid Securities Risk – The fund may invest in restricted or illiquid securities, including Rule 144A securities, which are securities that are not registered for sale to the general public under the Securities Act of 1933, as amended. These securities may be resold to certain institutional investors but, if at any time an insufficient number of qualified institutional buyers are interested in purchasing the securities, the fund may not have the ability to dispose of such securities promptly or at expected prices. As such, even if determined to be liquid, a fund’s investment in Rule 144A securities may subject the fund to enhanced liquidity risk and potentially increase the fund’s exposure to illiquid investments.
•
Market Risk – The value of securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.
•
Payment-in-Kind Securities Risk – Payment-in-kind securities carry additional risk as holders of these types of securities realize no cash until the cash payment date unless a portion of such securities is sold and, if the issuer defaults, the fund may obtain no return at all on its investment. The market price of payment-in-kind securities is affected by interest rate changes to a greater extent, and therefore tends to be more volatile, than that of securities which pay interest in cash.
•
Redemption Risk – The fund may need to sell securities at times it would not otherwise do so to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.
•
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 Y Class shares. The table shows how the fund’s average annual total 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.
The fund acquired the assets and assumed the historical performance of the Nomura High Yield Fund, a series of The Advisors’ Inner Circle Fund III (the “Predecessor Fund”) on October 2, 2017 (the “Reorganization”). Accordingly, the performance shown for periods prior to October 2, 2017 represents the performance of Class I shares of the Predecessor Fund. In addition, the Predecessor Fund acquired the assets and assumed the historical performance of the High Yield Fund, a series of Nomura Partners Funds, Inc. (the “Prior Predecessor Fund,” and together with the Predecessor Fund, the “Predecessor Funds”) on December 8, 2014 (the “Prior Reorganization”). Accordingly, the performance shown for periods before December 8, 2014 represents the performance of Class I shares of the Prior Predecessor Fund. The Predecessor Funds’ returns in the bar chart and table have not been adjusted to reflect the fund’s expenses. If the Predecessor Funds’ performance information had been adjusted to reflect the fund’s expenses, the performance may have been higher or lower for a given period depending on the expenses incurred by the Predecessor Funds for that period.
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 Y Class shares. The table shows how the fund’s average annual total 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 2019): 6.67% Lowest Performance Quarter (3Q 2015): -5.29%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Y Class year-to-date return was -4.45%.
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns For the calendar year ended December 31, 2019
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 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 After-tax returns are shown only for Y Class shares. After-tax returns for other share classes will vary.
Performance Table Closing [Text Block] rr_PerformanceTableClosingTextBlock
After-tax returns are shown only for Y 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.
Investment Trust Prospectus | HIGH INCOME FUND | ICE BofAML U.S. High Yield Constrained Index  
Prospectus: rr_ProspectusTable  
Index No Deduction for Fees, Expenses, Taxes [Text] rr_IndexNoDeductionForFeesExpensesTaxes (reflects no deduction for fees, expenses or taxes)
Label rr_AverageAnnualReturnLabel ICE BofA U.S. High Yield Constrained Index (reflects no deduction for fees, expenses or taxes)
1 Year rr_AverageAnnualReturnYear01 14.41%
5 Years rr_AverageAnnualReturnYear05 6.13%
Since Inception rr_AverageAnnualReturnSinceInception 5.78%
Inception Date rr_AverageAnnualReturnInceptionDate Dec. 27, 2012
Investment Trust Prospectus | HIGH INCOME FUND | INVESTOR CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AHIVX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee $ 25
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.78%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.79%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 81
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 253
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 439
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 978
Label rr_AverageAnnualReturnLabel Investor Class1 Return Before Taxes [8]
1 Year rr_AverageAnnualReturnYear01 12.32% [8]
5 Years rr_AverageAnnualReturnYear05 5.46% [8]
Since Inception rr_AverageAnnualReturnSinceInception 5.78% [8]
Inception Date rr_AverageAnnualReturnInceptionDate Oct. 02, 2017 [8]
Investment Trust Prospectus | HIGH INCOME FUND | I CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AHIIX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.68%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.69%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 71
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 221
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 385
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 859
Label rr_AverageAnnualReturnLabel I Class1 Return Before Taxes [8]
1 Year rr_AverageAnnualReturnYear01 12.44% [8]
5 Years rr_AverageAnnualReturnYear05 5.53% [8]
Since Inception rr_AverageAnnualReturnSinceInception 5.87% [8]
Inception Date rr_AverageAnnualReturnInceptionDate Oct. 02, 2017 [8]
Investment Trust Prospectus | HIGH INCOME FUND | Y CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol NPHIX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.58%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.59%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 60
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 189
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 330
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 738
Annual Return 2013 rr_AnnualReturn2013 11.80%
Annual Return 2014 rr_AnnualReturn2014 2.13%
Annual Return 2015 rr_AnnualReturn2015 (4.88%)
Annual Return 2016 rr_AnnualReturn2016 17.29%
Annual Return 2017 rr_AnnualReturn2017 6.98%
Annual Return 2018 rr_AnnualReturn2018 (2.01%)
Annual Return 2019 rr_AnnualReturn2019 12.67%
Year to Date Return, Label rr_YearToDateReturnLabel Y Class year-to-date return
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2020
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn (4.45%)
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Highest Performance Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Mar. 31, 2019
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 6.67%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Lowest Performance Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Sep. 30, 2015
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (5.29%)
Label rr_AverageAnnualReturnLabel Y Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 12.67%
5 Years rr_AverageAnnualReturnYear05 5.67%
Since Inception rr_AverageAnnualReturnSinceInception 6.00%
Inception Date rr_AverageAnnualReturnInceptionDate Dec. 27, 2012
Investment Trust Prospectus | HIGH INCOME FUND | Y CLASS | After Taxes on Distributions  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions
1 Year rr_AverageAnnualReturnYear01 10.13%
5 Years rr_AverageAnnualReturnYear05 3.02%
Since Inception rr_AverageAnnualReturnSinceInception 3.06%
Inception Date rr_AverageAnnualReturnInceptionDate Dec. 27, 2012
Investment Trust Prospectus | HIGH INCOME FUND | Y CLASS | After Taxes on Distributions and Sales  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions and Sale of Fund Shares
1 Year rr_AverageAnnualReturnYear01 7.44%
5 Years rr_AverageAnnualReturnYear05 3.11%
Since Inception rr_AverageAnnualReturnSinceInception 3.23%
Inception Date rr_AverageAnnualReturnInceptionDate Dec. 27, 2012
Investment Trust Prospectus | HIGH INCOME FUND | A CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AHIAX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice 4.50%
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none [9]
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.78%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.04%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 552
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 767
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 999
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,664
Label rr_AverageAnnualReturnLabel A Class1 Return Before Taxes [8]
1 Year rr_AverageAnnualReturnYear01 7.10% [8]
5 Years rr_AverageAnnualReturnYear05 4.23% [8]
Since Inception rr_AverageAnnualReturnSinceInception 4.83% [8]
Inception Date rr_AverageAnnualReturnInceptionDate Oct. 02, 2017 [8]
Investment Trust Prospectus | HIGH INCOME FUND | R5 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AHIEX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.58%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.59%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 60
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 189
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 330
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 738
Label rr_AverageAnnualReturnLabel R5 Class1 Return Before Taxes [8]
1 Year rr_AverageAnnualReturnYear01 12.68% [8]
5 Years rr_AverageAnnualReturnYear05 5.66% [8]
Since Inception rr_AverageAnnualReturnSinceInception 5.99% [8]
Inception Date rr_AverageAnnualReturnInceptionDate Oct. 02, 2017 [8]
Investment Trust Prospectus | HIGH INCOME FUND | R6 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AHIDX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.53%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.54%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 55
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 173
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 302
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 678
Label rr_AverageAnnualReturnLabel R6 Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 12.61%
Since Inception rr_AverageAnnualReturnSinceInception 4.84%
Inception Date rr_AverageAnnualReturnInceptionDate Oct. 02, 2017
Investment Trust Prospectus | HIGH-YIELD FUND  
Prospectus: rr_ProspectusTable  
Risk/Return [Heading] rr_RiskReturnHeading High-Yield Fund
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The fund seeks high current income.
Objective, Secondary [Text Block] rr_ObjectiveSecondaryTextBlock
As a secondary objective, the fund seeks capital appreciation, but only when consistent with its primary objective of maximizing current income.
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, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 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, Appendix A 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 38% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 38.00%
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 $100,000 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, Appendix A 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 $ 100,000
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 in high-yield corporate bonds and other debt securities with an emphasis on securities that are rated below investment-grade. A high-yield security, or junk bond, is one that has been rated below the four highest categories used by a nationally recognized statistical rating organization, or determined by the investment advisor to be of similar quality.
Under normal market conditions, the portfolio managers will maintain at least 80% of the fund’s net assets in high-yield corporate bonds and other debt instruments (including income-producing convertible and preferred securities, as well as loan participations and loan assignments). The remaining assets may be invested in common stocks or other equity-related securities. The fund may invest in new issuances of high yield securities, distressed securities and restricted or illiquid securities, including Rule 144A securities.
Up to 40% of the fund’s total assets may be invested in fixed-income obligations of foreign issuers. Under normal market conditions, the fund may invest up to 20% of its assets in short-term money market instruments and U.S. government securities.
The fund has no average maturity limitations, but it typically invests in intermediate-term and long-term debt securities.
The fund also may invest in derivative instruments such as options, futures contracts, options on futures contracts, and swaps (including credit default swaps), or in mortgage- or asset-backed securities, provided that such investments are in keeping with the fund’s investment objective. The fund may also engage in securities lending and invest its collateral in eligible securities.
To determine whether to buy or sell a security, the portfolio managers consider, among other things, various fund requirements and standards, along with economic conditions, alternative investments and interest rates.
Risk [Heading] rr_RiskHeading Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock
•
Credit Risk – High-yield debt securities are especially subject to credit risk. The inability or perceived inability of a security’s issuer to make interest and principal payments may cause the value of the security to decrease. As a result the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect.
•
High-Yield Risk – Issuers of high-yield securities are more vulnerable to real or perceived economic changes (such as an economic down turn or a prolonged period of rising interest rates), political changes or adverse developments specific to an issuer. These factors may be more likely to cause an issuer of low quality bonds to default on its obligations.
•
Liquidity Risk – During periods of market turbulence or unusually low trading activity, 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. The market for lower-quality debt securities is generally less liquid than the market for higher-quality securities. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments.
•
Interest Rate Risk – Investments in debt securities are also sensitive to interest rate changes. Generally, the value of debt securities and the funds that hold them decline as interest rates rise. Because the fund typically invests in intermediate-term and long-term bonds, the fund’s interest rate risk is generally higher than for funds with shorter-weighted average maturities, such as money market and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.
•
Restricted and Illiquid Securities Risk – The fund may invest in restricted or illiquid securities, including Rule 144A securities, which are securities that are not registered for sale to the general public under the Securities Act of 1933, as amended. These securities may be resold to certain institutional investors but, if at any time an insufficient number of qualified institutional buyers are interested in purchasing the securities, the fund may not have the ability to dispose of such securities promptly or at expected prices. As such, even if determined to be liquid, a fund’s investment in Rule 144A securities may subject the fund to enhanced liquidity risk and potentially increase the fund’s exposure to illiquid investments.
•
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.
•
Foreign Securities Risk – Foreign securities are generally riskier than U.S. securities. Political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), natural disasters and public health emergencies occurring in a country where the fund invests could cause the fund’s investments in that country to experience losses. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.
•
Securities Lending Risk – Securities lending involves the risk of loss of rights in, or delay in recovery of, the loaned securities if the borrower fails to return the security loaned or becomes insolvent.
•
Market Risk – The value of securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.
•
Loan Risk – In addition to the same general risks as debt securities, loans in which the fund invests may be exposed to restrictions on transfer, the inability or unwillingness of assignor(s) on whom the fund relies to demand and receive loan payments, and the risks of being a lender.
•
Redemption Risk – The fund may need to sell securities at times it would not otherwise do so to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.
•
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, 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 (4Q 2011): 7.13% Lowest Performance Quarter (3Q 2011): -6.81%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was -3.79%.
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns For the calendar year ended December 31, 2019
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.
Investment Trust Prospectus | HIGH-YIELD FUND | Bloomberg Barclay's U.S. High-Yield 2% Issuer Capped Bond Index  
Prospectus: rr_ProspectusTable  
Index No Deduction for Fees, Expenses, Taxes [Text] rr_IndexNoDeductionForFeesExpensesTaxes (reflects no deduction for fees, expenses or taxes)
Label rr_AverageAnnualReturnLabel Bloomberg Barclays U.S. High-Yield 2% Issuer Capped Bond Index    (reflects no deduction for fees, expenses or taxes)
1 Year rr_AverageAnnualReturnYear01 14.32%
5 Years rr_AverageAnnualReturnYear05 6.13%
10 Years rr_AverageAnnualReturnYear10 7.55%
Investment Trust Prospectus | HIGH-YIELD FUND | INVESTOR CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ABHIX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee $ 25
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.77% [10]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.78%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 80
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 250
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 434
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 966
Annual Return 2010 rr_AnnualReturn2010 13.41%
Annual Return 2011 rr_AnnualReturn2011 3.75%
Annual Return 2012 rr_AnnualReturn2012 15.04%
Annual Return 2013 rr_AnnualReturn2013 6.09%
Annual Return 2014 rr_AnnualReturn2014 1.39%
Annual Return 2015 rr_AnnualReturn2015 (5.58%)
Annual Return 2016 rr_AnnualReturn2016 13.97%
Annual Return 2017 rr_AnnualReturn2017 5.95%
Annual Return 2018 rr_AnnualReturn2018 (3.32%)
Annual Return 2019 rr_AnnualReturn2019 13.21%
Year to Date Return, Label rr_YearToDateReturnLabel Investor Class year-to-date return
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2020
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn (3.79%)
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Highest Performance Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Dec. 31, 2011
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 7.13%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Lowest Performance Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Sep. 30, 2011
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (6.81%)
Label rr_AverageAnnualReturnLabel Investor Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 13.21%
5 Years rr_AverageAnnualReturnYear05 4.53%
10 Years rr_AverageAnnualReturnYear10 6.15%
Inception Date rr_AverageAnnualReturnInceptionDate Sep. 30, 1997
Investment Trust Prospectus | HIGH-YIELD FUND | INVESTOR CLASS | After Taxes on Distributions  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions
1 Year rr_AverageAnnualReturnYear01 11.06%
5 Years rr_AverageAnnualReturnYear05 2.26%
10 Years rr_AverageAnnualReturnYear10 3.62%
Inception Date rr_AverageAnnualReturnInceptionDate Sep. 30, 1997
Investment Trust Prospectus | HIGH-YIELD FUND | INVESTOR CLASS | After Taxes on Distributions and Sales  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions and Sale of Fund Shares
1 Year rr_AverageAnnualReturnYear01 7.78%
5 Years rr_AverageAnnualReturnYear05 2.41%
10 Years rr_AverageAnnualReturnYear10 3.70%
Inception Date rr_AverageAnnualReturnInceptionDate Sep. 30, 1997
Investment Trust Prospectus | HIGH-YIELD FUND | I CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AHYHX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.67% [10]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.68%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 70
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 218
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 379
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 847
Label rr_AverageAnnualReturnLabel I Class1 Return Before Taxes [11]
1 Year rr_AverageAnnualReturnYear01 13.09% [11]
5 Years rr_AverageAnnualReturnYear05 4.68% [11]
10 Years rr_AverageAnnualReturnYear10 6.28% [11]
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 10, 2017 [11]
Investment Trust Prospectus | HIGH-YIELD FUND | Y CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AHYLX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.57% [10]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.58%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 59
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 186
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 324
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 726
Label rr_AverageAnnualReturnLabel Y Class1 Return Before Taxes [11]
1 Year rr_AverageAnnualReturnYear01 13.42% [11]
5 Years rr_AverageAnnualReturnYear05 4.77% [11]
10 Years rr_AverageAnnualReturnYear10 6.38% [11]
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 10, 2017 [11]
Investment Trust Prospectus | HIGH-YIELD FUND | A CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AHYVX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice 4.50%
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none [12]
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.77% [10]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.03%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 551
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 764
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 994
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,653
Label rr_AverageAnnualReturnLabel A Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 7.78%
5 Years rr_AverageAnnualReturnYear05 3.34%
10 Years rr_AverageAnnualReturnYear10 5.43%
Inception Date rr_AverageAnnualReturnInceptionDate Mar. 08, 2002
Investment Trust Prospectus | HIGH-YIELD FUND | C CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AHDCX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther 1.00%
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.77% [10]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 1.00%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.78%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 181
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 561
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 965
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 2,092
Label rr_AverageAnnualReturnLabel C Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 12.07%
5 Years rr_AverageAnnualReturnYear05 3.53%
10 Years rr_AverageAnnualReturnYear10 5.12%
Inception Date rr_AverageAnnualReturnInceptionDate Dec. 10, 2001
Investment Trust Prospectus | HIGH-YIELD FUND | R CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AHYRX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.77% [10]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.50%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.28%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 131
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 407
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 703
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,545
Label rr_AverageAnnualReturnLabel R Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 12.63%
5 Years rr_AverageAnnualReturnYear05 4.04%
10 Years rr_AverageAnnualReturnYear10 5.64%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 29, 2005
Investment Trust Prospectus | HIGH-YIELD FUND | R5 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACYIX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.57% [10]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.58%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 59
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 186
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 324
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 726
Label rr_AverageAnnualReturnLabel R5 Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 13.42%
5 Years rr_AverageAnnualReturnYear05 4.77%
10 Years rr_AverageAnnualReturnYear10 6.38%
Inception Date rr_AverageAnnualReturnInceptionDate Aug. 02, 2004
Investment Trust Prospectus | HIGH-YIELD FUND | R6 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AHYDX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.52% [10]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.53%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 54
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 170
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 297
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 665
Label rr_AverageAnnualReturnLabel R6 Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 13.50%
5 Years rr_AverageAnnualReturnYear05 4.79%
Since Inception rr_AverageAnnualReturnSinceInception 4.48%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 26, 2013
Investment Trust Prospectus | NT DIVERSIFIED BOND FUND  
Prospectus: rr_ProspectusTable  
Risk/Return [Heading] rr_RiskReturnHeading NT Diversified Bond Fund
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The fund seeks a high level of income by investing in non-money market debt securities.
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, hold and sell 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 128% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 128.00%
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 and that you earn a 5% return each year. The example also assumes that the fund’s operating expenses remain the same, except that it reflects the rate and duration of any fee waivers noted in the table above. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading] rr_StrategyHeading Principal Investment Strategies
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock
Under normal market conditions, the fund invests at least 80% of its net assets in high- and medium-grade, non-money market debt securities. These securities, which may be payable in U.S. or foreign currencies, may include corporate bonds and notes, government securities and securities backed by mortgages or other assets. Shorter-term debt securities round out the portfolio.
The fund invests most of its assets in investment-grade securities. An investment-grade security is one that has been rated by an independent rating agency in its top four credit quality categories or determined by the advisor to be of comparable credit quality. The weighted average maturity of the fund’s portfolio must be three and one-half years or longer.
The fund may invest in securities issued or guaranteed by the U.S. Treasury and certain U.S. government agencies or instrumentalities such as the Government National Mortgage Association (Ginnie Mae). Ginnie Mae is supported by the full faith and credit of the U.S. government. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank (FHLB) are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, they are authorized to borrow from the U.S. Treasury to meet their obligations.
In addition to the debt securities described above, the fund may also invest in bank loans.
The fund also may invest in derivative instruments provided that such investments are in keeping with the fund’s investment objective. Such derivatives may include options, futures contracts, options on futures contracts, and swaps (including credit default swaps). The fund may invest in collateralized debt obligations, including collateralized loan obligations, collateralized mortgage obligations, mortgage- or asset- backed securities, and other similarly structured investments. The fund may use foreign currency exchange contracts to shift investment exposure from one currency into another for hedging purposes.
The fund is not permitted to invest in securities issued by companies assigned the Global Industry Classification Standard (GICS) or the Bloomberg Industry Classification Standard (BICS) for the tobacco industry.
To determine whether to buy or sell a security, the portfolio managers consider, among other things, various fund requirements and standards, along with economic conditions, alternative investments and interest rates.
The fund may engage in active and frequent trading of portfolio securities to achieve its principal investment strategies. This may cause higher transaction costs and may affect performance. It may also result in the realization and distribution of capital gains.
Risk [Heading] rr_RiskHeading Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock
•
Interest Rate Risk – Investments in debt securities are sensitive to interest rate changes. Generally, the value of debt securities and the funds that hold them decline as interest rates rise. This fund is more susceptible to interest rate changes than funds that have shorter-weighted maturities, such as money market and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.
•
Credit Risk – The inability or perceived inability of a security’s issuer to make interest and principal payments may cause the value of the security to decrease. As a result the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect.
•
Prepayment Risk – The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds of similar maturity that invest less heavily in mortgage- and asset-backed securities.
•
Tobacco Exclusion – The fund’s prohibition on tobacco-related investments may cause it to forego profitable investment opportunities.
•
LIBOR Transition Risk – The fund may invest in instruments that have variable or floating coupon rates based on the London Interbank Offered Rate (“LIBOR”). LIBOR is a benchmark interest rate intended to be representative of the rate at which certain major international banks lend to one another over short-terms. Due to allegations of manipulation, LIBOR will be phased out by the end of 2021. Uncertainty remains regarding a replacement rate or rates for LIBOR. The transition process may lead to increased volatility or illiquidity in markets for instruments that rely on LIBOR. This could result in a change to the value of such instruments or a change in the cost of temporary borrowing for the fund.
•
Foreign Securities Risk – Foreign securities are generally riskier than U.S. securities. Political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), natural disasters and public health emergencies occurring in a country where the fund invests could cause the fund’s investments in that country to experience losses. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.
•
Emerging Market Risk – Investing in emerging market countries generally is also riskier than investing in foreign developed countries. Emerging market countries may have unstable governments and/or economies that are subject to sudden change, and significant volatility in their financial markets. These countries also may lack the legal, business and social framework to support securities markets.
•
Derivatives 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.
•
Bank Loan Risk – The market for bank loans may not be highly liquid and the fund may have difficulty selling them. In connection with purchasing loan participations, the fund generally will have no right to enforce compliance by borrowers with loan terms nor any set off rights, and the fund may not benefit directly from any posted collateral. As a result, the fund may be subject to the credit risk of both the borrower and the lender selling the participation. Bank loan transactions may take more than seven days to settle, meaning that proceeds would be unavailable to make additional investments or meet redemptions.
•
Collateralized Debt Obligations Risk – Collateralized debt obligations and collateralized loan obligations (CLOs) are subject to credit, interest rate, valuation, and prepayment and extension risks. These securities also are subject to risk of default on the underlying asset, particularly during periods of economic downturn. The market value of CLOs may be affected by, among other things, changes in the market value of the underlying assets held by the CLO, changes in the distributions on the underlying assets, defaults and recoveries on the underlying assets, capital gains and losses on the underlying assets, prepayments on underlying assets and the availability, prices and interest rate of underlying assets.
•
Liquidity Risk – During periods of market turbulence or unusually low trading activity, 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. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments.
•
Market Risk – The value of securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.
•
Redemption Risk – The fund may need to sell securities at times it would not otherwise do so to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.
•
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 G 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.
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 G 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 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 Return
Bar Chart Closing [Text Block] rr_BarChartClosingTextBlock
Highest Performance Quarter (3Q 2011): 3.44% Lowest Performance Quarter (4Q 2016): -3.05%

As of June 30, 2020, the most recent calendar quarter end, the fund’s G Class year-to-date return was 6.28%.
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns For the calendar year ended December 31, 2019
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.
Investment Trust Prospectus | NT DIVERSIFIED BOND FUND | Bloomberg Barclays U.S Aggregate Bond Index  
Prospectus: rr_ProspectusTable  
Index No Deduction for Fees, Expenses, Taxes [Text] rr_IndexNoDeductionForFeesExpensesTaxes (reflects no deduction for fees, expenses or taxes)
Label rr_AverageAnnualReturnLabel Bloomberg Barclays U.S. Aggregate Bond Index    (reflects no deduction for fees, expenses or taxes)
1 Year rr_AverageAnnualReturnYear01 8.72%
5 Years rr_AverageAnnualReturnYear05 3.05%
10 Years rr_AverageAnnualReturnYear10 3.74%
Investment Trust Prospectus | NT DIVERSIFIED BOND FUND | G CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACLDX
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.34%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.35%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets (0.34%) [13]
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.01%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 1
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 3
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 6
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 13
Annual Return 2010 rr_AnnualReturn2010 6.36%
Annual Return 2011 rr_AnnualReturn2011 7.46%
Annual Return 2012 rr_AnnualReturn2012 5.42%
Annual Return 2013 rr_AnnualReturn2013 (2.39%)
Annual Return 2014 rr_AnnualReturn2014 6.09%
Annual Return 2015 rr_AnnualReturn2015 0.44%
Annual Return 2016 rr_AnnualReturn2016 2.56%
Annual Return 2017 rr_AnnualReturn2017 3.86%
Annual Return 2018 rr_AnnualReturn2018 (0.84%)
Annual Return 2019 rr_AnnualReturn2019 8.96%
Year to Date Return, Label rr_YearToDateReturnLabel G Class year-to-date return
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2020
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn 6.28%
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Highest Performance Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Sep. 30, 2011
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 3.44%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Lowest Performance Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2016
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (3.05%)
Label rr_AverageAnnualReturnLabel G Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 8.96%
5 Years rr_AverageAnnualReturnYear05 2.94%
10 Years rr_AverageAnnualReturnYear10 3.73%
Investment Trust Prospectus | NT DIVERSIFIED BOND FUND | G CLASS | After Taxes on Distributions  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions
1 Year rr_AverageAnnualReturnYear01 7.70%
5 Years rr_AverageAnnualReturnYear05 1.75%
10 Years rr_AverageAnnualReturnYear10 2.47%
Investment Trust Prospectus | NT DIVERSIFIED BOND FUND | G CLASS | After Taxes on Distributions and Sales  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions and Sale of Fund Shares
1 Year rr_AverageAnnualReturnYear01 5.28%
5 Years rr_AverageAnnualReturnYear05 1.72%
10 Years rr_AverageAnnualReturnYear10 2.37%
Investment Trust Prospectus | NT HIGH INCOME FUND  
Prospectus: rr_ProspectusTable  
Risk/Return [Heading] rr_RiskReturnHeading NT High Income Fund
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The fund seeks current yield and 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, hold and sell 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 58% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 58.00%
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 (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
Under normal market conditions, the fund invests primarily in high-yield corporate bonds and other debt instruments with an emphasis on those that are rated below investment-grade. A high-yield security, or junk bond, is one that has been rated below the four highest categories used by a nationally recognized statistical rating organization, or, if unrated, determined by the investment advisor to be of similar quality.
Types of high-yield securities the fund may invest in include: bank loans in the form of assignments or participations; payment-in-kind securities; deferred payment securities; and fixed, variable, and floating rate obligations. The fund may invest in new issuances of high yield securities, distressed securities, and restricted or illiquid securities, including Rule 144A securities.
Bank loans include senior secured and unsecured floating rate loans of corporations, partnerships, or other entities. Typically these loans hold a senior position in the borrower’s capital structure, they have interest rates that reset frequently, and they may be secured by the borrower’s assets or they may be unsecured. The fund may invest up to 20% of its net assets in bank loan investments.
Deferred payment securities are zero-coupon securities that convert on a specified date to interest bearing debt securities. On this date, the stated coupon rate becomes effective and interest is paid at regular intervals.
The fund may invest in fixed-income instruments of foreign issuers, including emerging market issuers. Generally, the fund invests in U.S. dollar denominated securities, however, the fund may invest in securities denominated in foreign currencies.
The fund has no average maturity limitations, but it typically invests in intermediate-term and long-term debt securities. The fund may also invest in short-term money market instruments and U.S. government securities.
The fund is not permitted to invest in securities issued by companies assigned the Global Industry Classification Standard (GICS) or the Bloomberg Industry Classification Standard (BICS) for the tobacco industry.
To determine whether to buy or sell a security, the portfolio managers consider, among other things, various fund requirements and standards, along with economic conditions, alternative investments and interest rates.
Risk [Heading] rr_RiskHeading Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock
•
Credit Risk – The inability or perceived inability of a security’s issuer to make interest and principal payments may cause the value of the security to decrease. As a result, the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect.
•
High-Yield Risk – Issuers of high-yield securities are more vulnerable to real or perceived economic changes (such as an economic down turn or a prolonged period of rising interest rates), political changes or adverse developments specific to an issuer than issuers of investment grade debt securities. High-yield securities (junk bonds) are inherently speculative. These factors may be more likely to cause an issuer of high-yield bonds to default on its obligations.
•
Liquidity Risk – The market for lower-quality debt securities is generally less liquid than the market for higher-quality securities. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments. During periods of market turbulence or unusually low trading activity, 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.
•
Interest Rate Risk – Generally, the value of debt securities and the funds that hold them decline as interest rates rise. Because the fund typically invests in intermediate-term and long-term debt securities, the fund’s interest rate risk is generally higher than for funds with shorter-weighted average maturities, such as money market and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.
•
New Issue Risk – The market value of newly issued securities may fluctuate considerably due to factors such as the absence of a prior public market, unseasoned trading, the limited availability for trading, and limited information about the issuer.
•
Bank Loans Risk – When purchasing participations, the fund generally has no rights to enforce borrower compliance with the terms of the loan agreement, nor any rights of set-off against the borrower, and the fund may not benefit directly from any collateral supporting the loan. This means the fund assumes the credit risk of both the borrower and the lender that sells the participation. Investments in unsecured bank loans are subject to greater risk than investment in loans secured by collateral. Bank loan transactions may take more than seven days to settle, meaning that proceeds would be unavailable to make additional purchases or meet redemptions. Finally, bank loans may not be considered “securities” under the federal securities laws. Therefore, the fund may not be able to rely on the anti-fraud provisions of those laws.
•
Distressed Securities Risk – Distressed securities are speculative and involve substantial risk in addition to the risks of investing in high-yield bonds. Distressed securities frequently do not produce income while they are outstanding and may require the fund to bear certain extraordinary expenses to protect and recover its investment. Distressed securities are at high risk for default and may include securities that have already defaulted. The fund could lose its entire investment.
•
Deferred Payment Securities Risk – During the time that interest payments are not being made on these securities, holders are deemed to receive income (phantom income) annually, even though cash is not received. Additionally, these securities may be subject to greater price fluctuations when interest rates change than securities that currently pay interest. Longer term zero-coupon bonds are more exposed to this risk than those with shorter terms.
•
Foreign Securities Risk – Foreign securities are generally riskier than U.S. securities. Political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), natural disasters and public health emergencies occurring in a country where the fund invests could cause the fund’s investments in that country to experience losses. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.
•
Emerging Market Risk – Investing in emerging market countries generally is also riskier than investing in foreign developed countries. Emerging market countries may have unstable governments and/or economies that are subject to sudden change, and significant volatility in their financial markets. These countries also may lack the legal, business and social framework to support securities markets.
•
Restricted and Illiquid Securities Risk – The fund may invest in restricted or illiquid securities, including Rule 144A securities, which are securities that are not registered for sale to the general public under the Securities Act of 1933, as amended. These securities may be resold to certain institutional investors but, if at any time an insufficient number of qualified institutional buyers are interested in purchasing the securities, the fund may not have the ability to dispose of such securities promptly or at expected prices. As such, even if determined to be liquid, a fund’s investment in Rule 144A securities may subject the fund to enhanced liquidity risk and potentially increase the fund’s exposure to illiquid investments.
•
Market Risk – The value of securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.
•
Payment-in-Kind Securities Risk – Payment-in-kind securities carry additional risk as holders of these types of securities realize no cash until the cash payment date unless a portion of such securities is sold and, if the issuer defaults, the fund may obtain no return at all on its investment. The market price of payment-in-kind securities is affected by interest rate changes to a greater extent, and therefore tends to be more volatile, than that of securities which pay interest in cash.
•
Redemption Risk – The fund may need to sell securities at times it would not otherwise do so to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.
•
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.
•
Tobacco Exclusion – The fund’s prohibition on tobacco-related investments may cause it to forego profitable investment opportunities.
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.
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 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 Return
Bar Chart Closing [Text Block] rr_BarChartClosingTextBlock
Highest Performance Quarter (1Q 2019): 6.76%          Lowest Performance Quarter (4Q 2018): -5.74%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was (5.74)%.
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns For the calendar year ended December 31, 2019
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.
Investment Trust Prospectus | NT HIGH INCOME FUND | ICE BofAML U.S. High Yield Constrained Index  
Prospectus: rr_ProspectusTable  
Index No Deduction for Fees, Expenses, Taxes [Text] rr_IndexNoDeductionForFeesExpensesTaxes (reflects no deduction for fees, expenses or taxes)
Label rr_AverageAnnualReturnLabel ICE BofA U.S. High Yield Constrained Index (reflects no deduction for fees, expenses or taxes)
1 Year rr_AverageAnnualReturnYear01 14.41%
Since Inception rr_AverageAnnualReturnSinceInception 5.55%
Inception Date rr_AverageAnnualReturnInceptionDate May 19, 2017
Investment Trust Prospectus | NT HIGH INCOME FUND | INVESTOR CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AHGVX
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.78% [14]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.79%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.79%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 81
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 253
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 439
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 978
Annual Return 2018 rr_AnnualReturn2018 (3.18%)
Annual Return 2019 rr_AnnualReturn2019 12.77%
Year to Date Return, Label rr_YearToDateReturnLabel Investor Class year-to-date return
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2020
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn (5.74%)
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Highest Performance Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Mar. 31, 2019
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 6.76%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Lowest Performance Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Dec. 31, 2018
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (5.74%)
Label rr_AverageAnnualReturnLabel Investor Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 12.77%
Since Inception rr_AverageAnnualReturnSinceInception 4.59%
Inception Date rr_AverageAnnualReturnInceptionDate May 19, 2017
Investment Trust Prospectus | NT HIGH INCOME FUND | INVESTOR CLASS | After Taxes on Distributions  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions
1 Year rr_AverageAnnualReturnYear01 10.24%
Since Inception rr_AverageAnnualReturnSinceInception 2.26%
Inception Date rr_AverageAnnualReturnInceptionDate May 19, 2017
Investment Trust Prospectus | NT HIGH INCOME FUND | INVESTOR CLASS | After Taxes on Distributions and Sales  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions and Sale of Fund Shares
1 Year rr_AverageAnnualReturnYear01 7.50%
Since Inception rr_AverageAnnualReturnSinceInception 2.48%
Inception Date rr_AverageAnnualReturnInceptionDate May 19, 2017
Investment Trust Prospectus | NT HIGH INCOME FUND | G CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AHGNX
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.53% [14]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.54%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets (0.53%) [15]
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.01%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 1
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 3
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 6
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 13
Label rr_AverageAnnualReturnLabel G Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 13.51%
Since Inception rr_AverageAnnualReturnSinceInception 5.36%
Inception Date rr_AverageAnnualReturnInceptionDate May 19, 2017
Investment Trust Prospectus | PRIME MONEY MARKET FUND  
Prospectus: rr_ProspectusTable  
Risk/Return [Heading] rr_RiskReturnHeading Prime Money Market Fund
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The fund seeks to earn the highest level of current income while preserving the value of your investment.
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, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. More information about sales charges that may apply in certain circumstances where such shares were acquired by exchange from another American Century Investments fund, is available from your financial professional and in Calculation of Sales Charges on page 10 of the fund’s prospectus, Appendix A 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)
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 most of its assets in high-quality, very short-term debt securities issued by corporations, banks and federal, state and local governments.
Under normal market conditions, 25% or more of the fund’s assets are invested in obligations of issuers in the financial services industry. The debt securities in which the fund invests may include municipal securities and variable-rate securities. A municipal security is a taxable or tax-exempt debt obligation issued by or on behalf of a state, its political subdivisions, agencies or instrumentalities, the District of Columbia or a U.S. territory or possession. A variable-rate security is a debt obligation that provides for specified periodic interest rate adjustments based on changes in some index, such as the Secured Overnight Financing Rate (SOFR).
The fund may invest in securities issued or guaranteed by the U.S. Treasury and certain U.S. government agencies or instrumentalities such as the Government National Mortgage Association (Ginnie Mae). Ginnie Mae is supported by the full faith and credit of the U.S. government. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank (FHLB) are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, they are authorized to borrow from the U.S. Treasury to meet their obligations.
To determine whether to buy or sell a security, the portfolio managers consider, among other things, various fund requirements and standards, along with economic conditions, alternative investments and interest rates.
Because high-quality debt securities are among the safest securities available, the interest they pay is among the lowest for income-paying securities. Accordingly, the yield on this fund will likely be lower than the yield on funds that invest in longer-term or lower-quality securities.
Risk [Heading] rr_RiskHeading Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock
Even though the fund’s investments are designed to minimize interest rate, liquidity and credit risk, the fund is still subject to some degree of risk.
•
Interest Rate Risk – Interest rate risk means that the value of debt securities and funds that hold them decline as interest rates rise. A sharp and unexpected rise in interest rates could cause the fund’s price to drop.
•
Liquidity Risk – Changing regulatory or market conditions, including increases in interest rates or credit spreads, may adversely affect the liquidity of the fund’s investments. During periods of market turbulence or unusually low trading activity, 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.
•
Credit Risk – Credit risk is the risk that the inability or perceived inability of the issuer to make interest and principal payments will cause the value of the securities to decrease.
•
Redemption Risk – The fund may need to sell securities at times it would not otherwise do so to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.
•
Repurchase Agreement Risk – If the seller in a repurchase agreement transaction defaults on its obligation to repurchase a security at a mutually agreed-upon time and price under the agreement, the fund may suffer delays and incur costs or lose money in exercising its rights under the agreement.
•
Municipal Securities Risk – The fund is sensitive to events that affect municipal markets, including legislative or political changes and the financial condition of the issuers of municipal securities.
You could lose money by investing in the fund. Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The fund may impose a fee upon sale of your shares or may temporarily suspend your ability to sell shares if the fund’s liquidity falls below required minimums because of market conditions or other factors. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The fund’s sponsor has no legal obligation to provide financial support to the fund, and you should not expect that the sponsor will provide financial support to the fund at any time.
Risk Lose Money [Text] rr_RiskLoseMoney You could lose money by investing in the fund.
Risk Not Insured Depository Institution [Text] rr_RiskNotInsuredDepositoryInstitution An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Bar Chart and Performance Table [Heading] rr_BarChartAndPerformanceTableHeading Fund Performance
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock
The following bar chart and table provide some indication of the 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 fund’s past performance 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.
Performance Availability Website Address [Text] rr_PerformanceAvailabilityWebSiteAddress americancentury.com
Performance Past Does Not Indicate Future [Text] rr_PerformancePastDoesNotIndicateFuture The fund’s past performance 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 2019): 0.52%          Lowest Performance Quarter (1Q 2015):0.00%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 0.39%.
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns For the calendar year ended December 31, 2019
Investment Trust Prospectus | PRIME MONEY MARKET FUND | INVESTOR CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol BPRXX
Maximum Deferred Sales Charge (as a percentage of Offering Price) rr_MaximumDeferredSalesChargeOverOfferingPrice none
Maximum Account Fee rr_MaximumAccountFee $ 25
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.57%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.58%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 59
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 186
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 324
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 726
Annual Return 2010 rr_AnnualReturn2010 0.01%
Annual Return 2011 rr_AnnualReturn2011 0.01%
Annual Return 2012 rr_AnnualReturn2012 0.01%
Annual Return 2013 rr_AnnualReturn2013 0.01%
Annual Return 2014 rr_AnnualReturn2014 0.01%
Annual Return 2015 rr_AnnualReturn2015 0.01%
Annual Return 2016 rr_AnnualReturn2016 0.10%
Annual Return 2017 rr_AnnualReturn2017 0.59%
Annual Return 2018 rr_AnnualReturn2018 1.54%
Annual Return 2019 rr_AnnualReturn2019 1.82%
Year to Date Return, Label rr_YearToDateReturnLabel Investor Class year-to-date
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2020
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn 0.39%
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Highest Performance Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Mar. 31, 2019
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 0.52%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Lowest Performance Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Mar. 31, 2015
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn none
Label rr_AverageAnnualReturnLabel Investor Class
1 Year rr_AverageAnnualReturnYear01 1.82%
5 Years rr_AverageAnnualReturnYear05 0.81%
10 Years rr_AverageAnnualReturnYear10 0.41%
Investment Trust Prospectus | PRIME MONEY MARKET FUND | A CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACAXX
Maximum Deferred Sales Charge (as a percentage of Offering Price) rr_MaximumDeferredSalesChargeOverOfferingPrice none [16]
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.57%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.83%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 85
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 265
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 461
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,026
Label rr_AverageAnnualReturnLabel A Class
1 Year rr_AverageAnnualReturnYear01 1.57%
5 Years rr_AverageAnnualReturnYear05 0.70%
10 Years rr_AverageAnnualReturnYear10 0.35%
Investment Trust Prospectus | PRIME MONEY MARKET FUND | C CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ARCXX
Maximum Deferred Sales Charge (as a percentage of Offering Price) rr_MaximumDeferredSalesChargeOverOfferingPrice none [16]
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.57%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.75%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.33%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 136
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 422
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 730
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,601
Label rr_AverageAnnualReturnLabel C Class
1 Year rr_AverageAnnualReturnYear01 1.06%
5 Years rr_AverageAnnualReturnYear05 0.47%
10 Years rr_AverageAnnualReturnYear10 0.24%
Investment Trust Prospectus | SHORT DURATION FUND  
Prospectus: rr_ProspectusTable  
Risk/Return [Heading] rr_RiskReturnHeading Short Duration Fund
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The fund seeks to maximize total return.
Objective, Secondary [Text Block] rr_ObjectiveSecondaryTextBlock
As a secondary objective, the fund seeks a high level of income.
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, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 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 15 of the fund’s prospectus, Appendix A 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 156% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 156.00%
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 $100,000 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 15 of the fund’s prospectus, Appendix A 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 $ 100,000
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 invests at least 65% of its assets in investment-grade, non-money market debt securities. An investment-grade security is one that has been rated by a nationally recognized statistical rating organization in its top four credit quality categories or determined by the advisor to be of comparable credit quality. Debt securities include fixed-income investments such as notes, bonds, commercial paper and U.S. Treasury securities. These securities, which may be payable in U.S. or foreign currencies, may include corporate bonds and notes, government securities and securities backed by mortgages or other assets.
The fund may invest in high-yield debt securities. A high-yield security, or junk bond, is one that has been rated below the four highest categories used by a nationally recognized statistical rating organization, or determined by the investment advisor to be of similar quality. The fund may also invest in securities issued by companies that are located in emerging market countries. The fund may not invest more than 35% of its assets in high-yield securities.
No more than 10% of the fund’s assets may be invested in non-dollar denominated debt securities.
The fund may invest in securities issued or guaranteed by the U.S. Treasury and certain U.S. government agencies or instrumentalities such as the Government National Mortgage Association (Ginnie Mae). Ginnie Mae is supported by the full faith and credit of the U.S. government. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank (FHLB) are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, they are authorized to borrow from the U.S. Treasury to meet their obligations.
In addition to the debt securities described above, the fund may also invest in bank loans.
The fund also may invest in derivative instruments provided that such investments are in keeping with the fund’s investment objectives. Such derivatives may include options, futures contracts, options on futures contracts, and swaps (including credit default swaps). The fund may invest in collateralized debt obligations, including collateralized loan obligations, collateralized mortgage obligations, mortgage- or asset- backed securities, and other similarly structured investments. The fund may use foreign currency exchange contracts to shift investment exposure from one currency into another for hedging purposes or to enhance returns.
The weighted average duration of the fund’s portfolio must be three years or shorter. Duration is an indication of the relative sensitivity of a security’s market value to changes in interest rates. The longer the weighted average duration of the fund’s portfolio, the more sensitive its market value is to interest rate fluctuations. Duration is different from maturity in that it attempts to measure the interest rate sensitivity of a security, as opposed to its expected final maturity.
To determine whether to buy or sell a security, the portfolio managers consider, among other things, various fund requirements and standards, along with economic conditions, alternative investments and interest rates.
Risk [Heading] rr_RiskHeading Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock
•
Interest Rate Risk – Investments in debt securities are sensitive to interest rate changes. Generally, the value of debt securities and the funds that hold them decline as interest rates rise. A period of rising interest rates may negatively affect the fund’s performance.
•
Credit Risk – The inability or perceived inability of a security’s issuer to make interest and principal payments may cause the value of the security to decrease. As a result the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect.
•
High-Yield Risk – Issuers of high-yield securities are more vulnerable to real or perceived economic changes (such as an economic downturn or a prolonged period of rising interest rates), political changes or adverse developments specific to an issuer. These factors may be more likely to cause an issuer of low quality bonds to default on its obligations.
•
Liquidity Risk – During periods of market turbulence or unusually low trading activity, 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. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments.
•
Prepayment Risk – The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds of similar duration that invest less heavily in mortgage- and asset-backed securities.
•
LIBOR Transition Risk – The fund may invest in instruments that have variable or floating coupon rates based on the London Interbank Offered Rate (“LIBOR”). LIBOR is a benchmark interest rate intended to be representative of the rate at which certain major international banks lend to one another over short-terms. Due to allegations of manipulation, LIBOR will be phased out by the end of 2021. Uncertainty remains regarding a replacement rate or rates for LIBOR. The transition process may lead to increased volatility or illiquidity in markets for instruments that rely on LIBOR. This could result in a change to the value of such instruments or a change in the cost of temporary borrowing for the fund.
•
Foreign Securities Risk – Foreign securities are generally riskier than U.S. securities. Political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), natural disasters and public health emergencies occurring in a country where the fund invests could cause the fund’s investments in that country to experience losses. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.
•
Currency Risk – Because the fund may invest in securities denominated in foreign currencies, the fund could experience gains or losses based solely on changes in the exchange rate between foreign currencies and the U.S. dollar.
•
Emerging Market Risk – Investing in emerging market countries generally is also riskier than investing in foreign developed countries. Emerging market countries may have unstable governments and/or economies that are subject to sudden change, and significant volatility in their financial markets. These countries also may lack the legal, business and social framework to support securities markets.
•
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.
•
Bank Loan Risk – The market for bank loans may not be highly liquid and the fund may have difficulty selling them. In connection with purchasing loan participations, the fund generally will have no right to enforce compliance by borrowers with loan terms nor any set off rights, and the fund may not benefit directly from any posted collateral. As a result, the fund may be subject to the credit risk of both the borrower and the lender selling the participation. Bank loan transactions may take more than seven days to settle, meaning that proceeds would be unavailable to make additional investments or meet redemptions.
•
Collateralized Debt Obligations Risk – Collateralized debt obligations and collateralized loan obligations (CLOs) are subject to credit, interest rate, valuation, and prepayment and extension risks. These securities also are subject to risk of default on the underlying asset, particularly during periods of economic downturn. The market value of CLOs may be affected by, among other things, changes in the market value of the underlying assets held by the CLO, changes in the distributions on the underlying assets, defaults and recoveries on the underlying assets, capital gains and losses on the underlying assets, prepayments on underlying assets and the availability, prices and interest rate of underlying assets.
•
Market Risk – The value of securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.
•
Redemption Risk – The fund may need to sell securities at times it would not otherwise do so to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.
•
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, 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 (1Q 2019): 1.54%        Lowest Performance Quarter (2Q 2013): -0.72%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 2.00%.
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns For the calendar year ended December 31, 2019
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.
Investment Trust Prospectus | SHORT DURATION FUND | Bloomberg Barclays U.S. 1-3 Year Government Bond Index  
Prospectus: rr_ProspectusTable  
Index No Deduction for Fees, Expenses, Taxes [Text] rr_IndexNoDeductionForFeesExpensesTaxes  (reflects no deduction for fees, expenses or taxes)
Label rr_AverageAnnualReturnLabel Bloomberg Barclays U.S. 1-3 Year Government/Credit Bond Index    (reflects no deduction for fees, expenses or taxes)
1 Year rr_AverageAnnualReturnYear01 4.03%
5 Years rr_AverageAnnualReturnYear05 1.67%
10 Years rr_AverageAnnualReturnYear10 1.54%
Investment Trust Prospectus | SHORT DURATION FUND | INVESTOR CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACSNX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee $ 25
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.58%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.59%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 60
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 189
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 330
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 738
Annual Return 2010 rr_AnnualReturn2010 3.29%
Annual Return 2011 rr_AnnualReturn2011 2.00%
Annual Return 2012 rr_AnnualReturn2012 2.14%
Annual Return 2013 rr_AnnualReturn2013 0.21%
Annual Return 2014 rr_AnnualReturn2014 0.53%
Annual Return 2015 rr_AnnualReturn2015 0.84%
Annual Return 2016 rr_AnnualReturn2016 1.92%
Annual Return 2017 rr_AnnualReturn2017 1.41%
Annual Return 2018 rr_AnnualReturn2018 1.33%
Annual Return 2019 rr_AnnualReturn2019 3.95%
Year to Date Return, Label rr_YearToDateReturnLabel Investor Class year-to-date return
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2020
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn 2.00%
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Highest Performance Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Mar. 31, 2019
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 1.54%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Lowest Performance Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Jun. 30, 2013
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (0.72%)
Label rr_AverageAnnualReturnLabel Investor Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 3.95%
5 Years rr_AverageAnnualReturnYear05 1.88%
10 Years rr_AverageAnnualReturnYear10 1.76%
Inception Date rr_AverageAnnualReturnInceptionDate Nov. 30, 2006
Investment Trust Prospectus | SHORT DURATION FUND | INVESTOR CLASS | After Taxes on Distributions  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions
1 Year rr_AverageAnnualReturnYear01 2.86%
5 Years rr_AverageAnnualReturnYear05 1.00%
10 Years rr_AverageAnnualReturnYear10 0.98%
Inception Date rr_AverageAnnualReturnInceptionDate Nov. 30, 2006
Investment Trust Prospectus | SHORT DURATION FUND | INVESTOR CLASS | After Taxes on Distributions and Sales  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions and Sale of Fund Shares
1 Year rr_AverageAnnualReturnYear01 2.33%
5 Years rr_AverageAnnualReturnYear05 1.05%
10 Years rr_AverageAnnualReturnYear10 1.02%
Inception Date rr_AverageAnnualReturnInceptionDate Nov. 30, 2006
Investment Trust Prospectus | SHORT DURATION FUND | I CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASHHX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.48%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.49%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 50
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 157
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 275
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 617
Label rr_AverageAnnualReturnLabel I Class1 Return Before Taxes [17]
1 Year rr_AverageAnnualReturnYear01 4.06% [17]
5 Years rr_AverageAnnualReturnYear05 1.99% [17]
10 Years rr_AverageAnnualReturnYear10 1.85% [17]
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 10, 2017 [17]
Investment Trust Prospectus | SHORT DURATION FUND | A CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACSQX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice 2.25%
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none [18]
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.58%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.84%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 309
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 487
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 681
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,239
Label rr_AverageAnnualReturnLabel A Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 1.38%
5 Years rr_AverageAnnualReturnYear05 1.16%
10 Years rr_AverageAnnualReturnYear10 1.27%
Inception Date rr_AverageAnnualReturnInceptionDate Nov. 30, 2006
Investment Trust Prospectus | SHORT DURATION FUND | C CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACSKX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther 1.00%
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.58%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 1.00%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.59%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 162
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 503
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 866
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,888
Label rr_AverageAnnualReturnLabel C Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 3.02%
5 Years rr_AverageAnnualReturnYear05 0.89%
10 Years rr_AverageAnnualReturnYear10 0.75%
Inception Date rr_AverageAnnualReturnInceptionDate Nov. 30, 2006
Investment Trust Prospectus | SHORT DURATION FUND | R CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACSPX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.58%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.50%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.09%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 111
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 347
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 602
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,329
Label rr_AverageAnnualReturnLabel R Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 3.43%
5 Years rr_AverageAnnualReturnYear05 1.40%
10 Years rr_AverageAnnualReturnYear10 1.26%
Inception Date rr_AverageAnnualReturnInceptionDate Nov. 30, 2006
Investment Trust Prospectus | SHORT DURATION FUND | R5 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ACSUX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.38%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.39%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 40
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 126
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 219
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 493
Label rr_AverageAnnualReturnLabel R5 Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 4.16%
5 Years rr_AverageAnnualReturnYear05 2.09%
10 Years rr_AverageAnnualReturnYear10 1.96%
Inception Date rr_AverageAnnualReturnInceptionDate Nov. 30, 2006
Investment Trust Prospectus | SHORT DURATION FUND | R6 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASDDX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.33%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.34%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 35
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 110
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 191
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 431
Label rr_AverageAnnualReturnLabel R6 Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 4.21%
Since Inception rr_AverageAnnualReturnSinceInception 2.39%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2017
Investment Trust Prospectus | SHORT DURATION INFLATION PROTECTION BOND FUND  
Prospectus: rr_ProspectusTable  
Risk/Return [Heading] rr_RiskReturnHeading Short Duration Inflation Protection Bond Fund
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The fund pursues total return using a strategy that seeks to protect against U.S. inflation.
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, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 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 15 of the fund’s prospectus, Appendix A 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 50% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 50.00%
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 $100,000 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 15 of the fund’s prospectus, Appendix A 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 $ 100,000
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. The example also assumes that the fund’s operating expenses remain the same, except that it reflects the rate and duration of any fee waivers noted in the table above. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading] rr_StrategyHeading Principal Investment Strategies
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock
Under normal market conditions, the fund invests at least 80% of its net assets in inflation-linked debt securities. These securities include inflation-linked U.S. Treasury securities, inflation-linked securities issued by U.S. government agencies and instrumentalities other than the U.S. Treasury, and inflation-linked securities issued by other entities such as domestic and foreign corporations and governments. Inflation-linked securities are designed to protect the future purchasing power of the money invested in them.
The fund may invest in securities issued or guaranteed by the U.S. Treasury and certain U.S. government agencies or instrumentalities such as the Government National Mortgage Association (Ginnie Mae). Ginnie Mae is supported by the full faith and credit of the U.S. government. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank (FHLB) are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, they are authorized to borrow from the U.S. Treasury to meet their obligations.
The fund also may invest a portion of its net assets in fixed-income securities that are not linked to inflation. These securities may include other debt securities, including mortgage- and asset-backed securities, whether issued by the U.S. government, its agencies or instrumentalities, corporations or other non-governmental issuers.
The fund may invest up to 20% of its total assets in securities denominated in foreign currencies and may invest beyond this limit in U.S. dollar denominated securities of foreign issuers. The fund invests primarily in investment-grade securities, but may also invest a portion of its assets in high-yield securities, or junk bonds.
The fund also may invest in derivative instruments such as options, futures contracts, options on futures contracts, and swaps (including inflation and credit default swaps), or in mortgage- or asset-backed securities, provided that such instruments are in keeping with the fund’s investment objective.
The weighted average duration of the fund’s portfolio must be five years or shorter. Duration is an indication of the relative sensitivity of a security’s market value to changes in interest rates. The longer the weighted average duration of the fund’s portfolio, the more sensitive its market value is to interest rate fluctuations. Duration is different from maturity in that it attempts to measure the interest rate sensitivity of a security, as opposed to its expected final maturity.
To determine whether to buy or sell a security, the portfolio managers consider, among other things, various fund requirements and standards, along with economic conditions, alternative investments and interest rates.
Risk [Heading] rr_RiskHeading Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock
•
Interest Rate Risk – Inflation-linked securities trade at prevailing real interest rates. Generally, when real interest rates rise, the value of the fund’s debt securities will decline. The opposite is true when real interest rates decline. The real interest rate is the current market interest rate minus the market’s inflation expectations. A period of rising interest rates may negatively affect the fund’s performance.
•
Credit Risk – The inability or perceived inability of a security’s issuer to make interest and principal payments may cause the value of the security to decrease. As a result the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect.
•
High-Yield Risk – Issuers of high-yield securities are more vulnerable to real or perceived economic changes (such as an economic downturn or a prolonged period of rising interest rates), political changes or adverse developments specific to an issuer. These factors may be more likely to cause an issuer of low quality bonds to default on its obligations.
•
Liquidity Risk – During periods of market turbulence or unusually low trading activity, 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. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments.
•
Prepayment Risk – The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds of similar duration that invest less heavily in mortgage- and asset-backed securities.
•
Derivatives 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.
•
Foreign Securities Risk – Foreign securities are generally riskier than U.S. securities. Political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), natural disasters and public health emergencies occurring in a country where the fund invests could cause the fund’s investments in that country to experience losses. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.
•
Market Risk – The value of securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.
•
Redemption Risk – The fund may need to sell securities at times it would not otherwise do so to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.
•
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, 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 (2Q 2010): 3.51%    Lowest Performance Quarter (2Q 2013): -3.25%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 1.45%.
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns For the calendar year ended December 31, 2019
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.
Investment Trust Prospectus | SHORT DURATION INFLATION PROTECTION BOND FUND | Bloomberg Barclay's 1-5 Year Treasury Inflation Index  
Prospectus: rr_ProspectusTable  
Index No Deduction for Fees, Expenses, Taxes [Text] rr_IndexNoDeductionForFeesExpensesTaxes  (reflects no deduction for fees, expenses or taxes)
Label rr_AverageAnnualReturnLabel Bloomberg Barclays U.S. 1-5 Year Treasury Inflation Protected Securities (TIPS) Index  (reflects no deduction for fees, expenses or taxes)
1 Year rr_AverageAnnualReturnYear01 5.08%
5 Years rr_AverageAnnualReturnYear05 1.84%
10 Years rr_AverageAnnualReturnYear10 1.73%
Investment Trust Prospectus | SHORT DURATION INFLATION PROTECTION BOND FUND | INVESTOR CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol APOIX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee $ 25
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.56%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.57%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.57%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 58
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 183
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 319
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 714
Annual Return 2010 rr_AnnualReturn2010 5.46%
Annual Return 2011 rr_AnnualReturn2011 8.80%
Annual Return 2012 rr_AnnualReturn2012 3.44%
Annual Return 2013 rr_AnnualReturn2013 (2.28%)
Annual Return 2014 rr_AnnualReturn2014 (1.73%)
Annual Return 2015 rr_AnnualReturn2015 (0.50%)
Annual Return 2016 rr_AnnualReturn2016 3.25%
Annual Return 2017 rr_AnnualReturn2017 0.73%
Annual Return 2018 rr_AnnualReturn2018 0.07%
Annual Return 2019 rr_AnnualReturn2019 4.77%
Year to Date Return, Label rr_YearToDateReturnLabel Investor Class year-to-date return
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2020
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn 1.45%
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Highest Performance Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Jun. 30, 2010
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 3.51%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Lowest Performance Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Jun. 30, 2013
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (3.25%)
Label rr_AverageAnnualReturnLabel Investor Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 4.77%
5 Years rr_AverageAnnualReturnYear05 1.65%
10 Years rr_AverageAnnualReturnYear10 2.15%
Inception Date rr_AverageAnnualReturnInceptionDate May 31, 2005
Investment Trust Prospectus | SHORT DURATION INFLATION PROTECTION BOND FUND | INVESTOR CLASS | After Taxes on Distributions  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions
1 Year rr_AverageAnnualReturnYear01 4.06%
5 Years rr_AverageAnnualReturnYear05 1.15%
10 Years rr_AverageAnnualReturnYear10 1.37%
Inception Date rr_AverageAnnualReturnInceptionDate May 31, 2005
Investment Trust Prospectus | SHORT DURATION INFLATION PROTECTION BOND FUND | INVESTOR CLASS | After Taxes on Distributions and Sales  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions and Sale of Fund Shares
1 Year rr_AverageAnnualReturnYear01 2.83%
5 Years rr_AverageAnnualReturnYear05 1.04%
10 Years rr_AverageAnnualReturnYear10 1.39%
Inception Date rr_AverageAnnualReturnInceptionDate May 31, 2005
Investment Trust Prospectus | SHORT DURATION INFLATION PROTECTION BOND FUND | I CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol APOHX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.46%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.47%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.47%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 48
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 151
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 264
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 592
Label rr_AverageAnnualReturnLabel I Class1 Return Before Taxes [19]
1 Year rr_AverageAnnualReturnYear01 4.84% [19]
5 Years rr_AverageAnnualReturnYear05 1.75% [19]
10 Years rr_AverageAnnualReturnYear10 2.25% [19]
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 10, 2017 [19]
Investment Trust Prospectus | SHORT DURATION INFLATION PROTECTION BOND FUND | Y CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol APOYX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.36%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.37%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.37%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 38
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 119
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 208
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 469
Label rr_AverageAnnualReturnLabel Y Class1 Return Before Taxes [19]
1 Year rr_AverageAnnualReturnYear01 4.94% [19]
5 Years rr_AverageAnnualReturnYear05 1.85% [19]
10 Years rr_AverageAnnualReturnYear10 2.36% [19]
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 10, 2017 [19]
Investment Trust Prospectus | SHORT DURATION INFLATION PROTECTION BOND FUND | A CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol APOAX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice 2.25%
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none [20]
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.56%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.82%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.82%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 307
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 481
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 670
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,216
Label rr_AverageAnnualReturnLabel A Class2 Return Before Taxes [21]
1 Year rr_AverageAnnualReturnYear01 2.06% [21]
5 Years rr_AverageAnnualReturnYear05 0.91% [21]
10 Years rr_AverageAnnualReturnYear10 1.66% [21]
Inception Date rr_AverageAnnualReturnInceptionDate May 31, 2005 [21]
Investment Trust Prospectus | SHORT DURATION INFLATION PROTECTION BOND FUND | C CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol APOCX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther 1.00%
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.56%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 1.00%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.57%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 1.57%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 160
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 496
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 856
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,866
Label rr_AverageAnnualReturnLabel C Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 3.77%
5 Years rr_AverageAnnualReturnYear05 0.63%
10 Years rr_AverageAnnualReturnYear10 1.14%
Inception Date rr_AverageAnnualReturnInceptionDate May 31, 2005
Investment Trust Prospectus | SHORT DURATION INFLATION PROTECTION BOND FUND | R CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol APORX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.56%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.50%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.07%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 1.07%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 109
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 341
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 591
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,306
Label rr_AverageAnnualReturnLabel R Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 4.30%
5 Years rr_AverageAnnualReturnYear05 1.14%
10 Years rr_AverageAnnualReturnYear10 1.64%
Inception Date rr_AverageAnnualReturnInceptionDate May 31, 2005
Investment Trust Prospectus | SHORT DURATION INFLATION PROTECTION BOND FUND | R5 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol APISX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.36%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.37%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.37%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 38
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 119
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 208
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 469
Label rr_AverageAnnualReturnLabel R5 Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 4.94%
5 Years rr_AverageAnnualReturnYear05 1.86%
10 Years rr_AverageAnnualReturnYear10 2.36%
Inception Date rr_AverageAnnualReturnInceptionDate May 31, 2005
Investment Trust Prospectus | SHORT DURATION INFLATION PROTECTION BOND FUND | R6 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol APODX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.31%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.32%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.32%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 33
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 103
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 180
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 406
Label rr_AverageAnnualReturnLabel R6 Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 5.00%
5 Years rr_AverageAnnualReturnYear05 1.91%
Since Inception rr_AverageAnnualReturnSinceInception 1.24%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 26, 2013
Investment Trust Prospectus | SHORT DURATION INFLATION PROTECTION BOND FUND | G CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol APOGX
Maximum Sales Charge Imposed on Purchases (as a percentage of Offering Price) rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.31%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.32%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets (0.31%) [22]
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.01%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 1
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 3
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 6
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 13
Label rr_AverageAnnualReturnLabel G Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 5.42%
Since Inception rr_AverageAnnualReturnSinceInception 2.62%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2017
Investment Trust Prospectus | SHORT DURATION STRATEGIC INCOME FUND  
Prospectus: rr_ProspectusTable  
Risk/Return [Heading] rr_RiskReturnHeading Short Duration Strategic Income Fund
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The fund seeks income.
Objective, Secondary [Text Block] rr_ObjectiveSecondaryTextBlock
As a secondary objective, the fund seeks long-term capital appreciation.
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, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 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 16 of the fund’s prospectus, Appendix A 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 98% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 98.00%
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 $100,000 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 16 of the fund’s prospectus, Appendix A 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 $ 100,000
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 invests in both investment-grade and high-yield, non-money market debt securities. These securities may include corporate bonds and notes, government securities and securities backed by mortgages or other assets. Investment grade securities are those that have been rated in one of the top four credit quality categories by an independent rating agency or determined by the advisor to be of comparable credit quality. High-yield securities, which are also known as “junk bonds”, are those that have been rated by an independent rating agency below the highest four categories or determined by the advisor to be of similar quality. 
The debt securities in which the fund invests may be payable in U.S. or foreign currencies. 
The fund may also invest in certain equity securities such as preferred stock, convertible securities or equity equivalents provided that such investments are consistent with the fund’s investment objectives.
The fund may invest in securities issued or guaranteed by the U.S. Treasury and certain U.S. government agencies or instrumentalities such as the Government National Mortgage Association (Ginnie Mae). Ginnie Mae is supported by the full faith and credit of the U.S. government. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank (FHLB) are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, they are authorized to borrow from the U.S. Treasury to meet their obligations.
In addition to the securities listed above, the fund may also invest in bank loans.
The fund may also utilize derivative instruments provided that such investments are in keeping with the fund’s investment objectives. Such derivative instruments may include options, futures contracts, options on futures contracts, and swaps (such as credit default swaps either on a single issuer or a securities index). The fund may invest in collateralized debt obligations, including collateralized loan obligations, collateralized mortgage obligations, mortgage- or asset- backed securities, and other similarly structured investments. The fund may use foreign currency exchange contracts to shift investment exposure from one currency into another for hedging purposes or to enhance returns.
The weighted average duration of the fund’s portfolio must be three years or shorter. Duration is an indication of the relative sensitivity of a security’s market value to changes in interest rates. The longer the weighted average duration of the fund’s portfolio, the more sensitive its market value is to interest rate fluctuations. Duration is different from maturity in that it attempts to measure the interest rate sensitivity of a security, as opposed to its expected final maturity. For example, if the weighted average duration of the fund’s portfolio is two years, a 2% change in the value of the fund’s portfolio would be expected for every 1% change in interest rates.
To determine whether to buy or sell a security, the portfolio managers consider, among other things, various fund requirements and standards, along with economic conditions, alternative investments and interest rates.
The portfolio managers may engage in hedging of portfolio positions, which usually involves entering into a derivative transaction that has the opposite characteristic of the position being hedged. The net effect of the two positions is intended to reduce or eliminate the exposure created by the first position.
To gain exposure to certain segments of the fixed-income market, the fund may invest in other American Century funds (affiliated funds), unaffiliated funds, securities and other financial instruments.
Risk [Heading] rr_RiskHeading Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock
•
Interest Rate Risk – Investments in debt securities are sensitive to interest rate changes. Generally, the value of debt securities and the funds that hold them decline as interest rates rise. A period of rising interest rates may negatively affect the fund’s performance.
•
Credit Risk – The inability or perceived inability of a security’s issuer to make interest and principal payments may cause the value of the security to decrease. As a result the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect.
•
High-Yield Risk – Issuers of high-yield securities are more vulnerable to real or perceived economic changes (such as an economic downturn or a prolonged period of rising interest rates), political changes or adverse developments specific to an issuer. These factors may be more likely to cause an issuer of low quality bonds to default on its obligations.
•
LIBOR Transition Risk – The fund may invest in instruments that have variable or floating coupon rates based on the London Interbank Offered Rate (“LIBOR”). LIBOR is a benchmark interest rate intended to be representative of the rate at which certain major international banks lend to one another over short-terms. Due to allegations of manipulation, LIBOR will be phased out by the end of 2021. Uncertainty remains regarding a replacement rate or rates for LIBOR. The transition process may lead to increased volatility or illiquidity in markets for instruments that rely on LIBOR. This could result in a change to the value of such instruments or a change in the cost of temporary borrowing for the fund.
•
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. Derivatives can be highly illiquid and difficult to unwind or value, and changes in the value of a derivative held by the fund may not correlate with the value of the underlying instrument or the fund’s other investments.
•
Bank Loan Risk – The market for bank loans may not be highly liquid and the fund may have difficulty selling them. In connection with purchasing loan participations, the fund generally will have no right to enforce compliance by borrowers with loan terms nor any set off rights, and the fund may not benefit directly from any posted collateral. As a result, the fund may be subject to the credit risk of both the borrower and the lender selling the participation. Bank loan transactions may take more than seven days to settle, meaning that proceeds would be unavailable to make additional investments or meet redemptions.
•
Collateralized Debt Obligations Risk – Collateralized debt obligations and collateralized loan obligations (CLOs) are subject to credit, interest rate, valuation, and prepayment and extension risks. These securities also are subject to risk of default on the underlying asset, particularly during periods of economic downturn. The market value of CLOs may be affected by, among other things, changes in the market value of the underlying assets held by the CLO, changes in the distributions on the underlying assets, defaults and recoveries on the underlying assets, capital gains and losses on the underlying assets, prepayments on underlying assets and the availability, prices and interest rate of underlying assets.
•
Counterparty Risk – If the fund enters into financial contracts, the fund will be subject to the credit risk presented by counterparties.
•
Liquidity Risk – During periods of market turbulence or unusually low trading activity, 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. In addition, when the market for certain investments is illiquid, the fund may be unable to achieve its desired level of exposure to a certain sector. Illiquid securities may be difficult to value. Changing regulatory and market conditions, including increases in interest rates and credit spreads, may adversely affect the liquidity of the fund’s investments.
•
Prepayment Risk – The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds of similar maturity that invest less heavily in mortgage- and asset-backed securities.
•
Foreign Securities Risk – Foreign securities are generally riskier than U.S. securities. Political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), natural disasters and public health emergencies occurring in a country where the fund invests could cause the fund’s investments in that country to experience losses. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.
•
Currency Risk – Because the fund may invest in securities denominated in foreign currencies, the fund could experience gains or losses based solely on changes in the exchange rate between foreign currencies and the U.S. dollar.
•
Convertible Securities Risk – The fund may invest in convertible securities, which may be affected by changes in interest rates, the credit of the issuer, and the value of the underlying common stock. In addition, because these securities are convertible into common stock, they are subject to general stock market risk, though to a lesser degree.
•
Market Risk – The value of securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.
•
Redemption Risk – The fund may need to sell securities at times it would not otherwise do so to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.
•
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, 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 (1Q 2019): 2.33%    Lowest Performance Quarter (3Q 2015): -2.07%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 1.37%.
Performance Table Heading rr_PerformanceTableHeading Average Annual Total ReturnsFor the calendar year ended December 31, 2019
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.
Investment Trust Prospectus | SHORT DURATION STRATEGIC INCOME FUND | Bloomberg Barclays U.S. 1-3 Year Government Bond Index  
Prospectus: rr_ProspectusTable  
Index No Deduction for Fees, Expenses, Taxes [Text] rr_IndexNoDeductionForFeesExpensesTaxes (reflects no deduction for fees, expenses or taxes)
Label rr_AverageAnnualReturnLabel Bloomberg Barclays U.S. 1-3 Year Government/Credit Bond Index    (reflects no deduction for fees, expenses or taxes)
1 Year rr_AverageAnnualReturnYear01 4.03%
5 Years rr_AverageAnnualReturnYear05 1.67%
Since Inception rr_AverageAnnualReturnSinceInception 1.59%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | SHORT DURATION STRATEGIC INCOME FUND | INVESTOR CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASDVX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee $ 25
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.51% [23]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.52%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 53
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 167
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 291
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 653
Annual Return 2015 rr_AnnualReturn2015 (0.81%)
Annual Return 2016 rr_AnnualReturn2016 5.44%
Annual Return 2017 rr_AnnualReturn2017 2.80%
Annual Return 2018 rr_AnnualReturn2018 0.25%
Annual Return 2019 rr_AnnualReturn2019 5.23%
Year to Date Return, Label rr_YearToDateReturnLabel Investor Class year-to-date return
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2020
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn 1.37%
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Highest Performance Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Mar. 31, 2019
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 2.33%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Lowest Performance Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Sep. 30, 2015
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (2.07%)
Label rr_AverageAnnualReturnLabel Investor Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 5.23%
5 Years rr_AverageAnnualReturnYear05 2.55%
Since Inception rr_AverageAnnualReturnSinceInception 2.11%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | SHORT DURATION STRATEGIC INCOME FUND | INVESTOR CLASS | After Taxes on Distributions  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions
1 Year rr_AverageAnnualReturnYear01 4.00%
5 Years rr_AverageAnnualReturnYear05 1.33%
Since Inception rr_AverageAnnualReturnSinceInception 0.86%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | SHORT DURATION STRATEGIC INCOME FUND | INVESTOR CLASS | After Taxes on Distributions and Sales  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions and Sale of Fund Shares
1 Year rr_AverageAnnualReturnYear01 3.08%
5 Years rr_AverageAnnualReturnYear05 1.40%
Since Inception rr_AverageAnnualReturnSinceInception 1.04%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | SHORT DURATION STRATEGIC INCOME FUND | I CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASDHX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.41% [23]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.42%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 43
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 135
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 236
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 530
Label rr_AverageAnnualReturnLabel I Class1 Return Before Taxes [24]
1 Year rr_AverageAnnualReturnYear01 5.22% [24]
5 Years rr_AverageAnnualReturnYear05 2.63% [24]
Since Inception rr_AverageAnnualReturnSinceInception 2.18% [24]
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 10, 2017 [24]
Investment Trust Prospectus | SHORT DURATION STRATEGIC INCOME FUND | Y CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASYDX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.31% [23]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.32%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 33
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 103
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 180
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 406
Label rr_AverageAnnualReturnLabel Y Class1 Return Before Taxes [24]
1 Year rr_AverageAnnualReturnYear01 5.31% [24]
5 Years rr_AverageAnnualReturnYear05 2.74% [24]
Since Inception rr_AverageAnnualReturnSinceInception 2.31% [24]
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 10, 2017 [24]
Investment Trust Prospectus | SHORT DURATION STRATEGIC INCOME FUND | A CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASADX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice 2.25%
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none [25]
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.51% [23]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.77%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 302
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 466
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 644
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,158
Label rr_AverageAnnualReturnLabel A Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 2.45%
5 Years rr_AverageAnnualReturnYear05 1.84%
Since Inception rr_AverageAnnualReturnSinceInception 1.44%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | SHORT DURATION STRATEGIC INCOME FUND | C CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASCDX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther 1.00%
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.51% [23]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 1.00%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.52%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 155
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 481
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 830
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,811
Label rr_AverageAnnualReturnLabel C Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 4.18%
5 Years rr_AverageAnnualReturnYear05 1.53%
Since Inception rr_AverageAnnualReturnSinceInception 1.10%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | SHORT DURATION STRATEGIC INCOME FUND | R CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASDRX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.51% [23]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.50%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.02%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 104
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 325
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 564
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,248
Label rr_AverageAnnualReturnLabel R Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 4.59%
5 Years rr_AverageAnnualReturnYear05 2.04%
Since Inception rr_AverageAnnualReturnSinceInception 1.61%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | SHORT DURATION STRATEGIC INCOME FUND | R5 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASDJX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.31% [23]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.32%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 33
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 103
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 180
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 406
Label rr_AverageAnnualReturnLabel R5 Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 5.33%
5 Years rr_AverageAnnualReturnYear05 2.75%
Since Inception rr_AverageAnnualReturnSinceInception 2.32%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | SHORT DURATION STRATEGIC INCOME FUND | R6 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASXDX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.26% [23]
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.27%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 28
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 87
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 152
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 344
Label rr_AverageAnnualReturnLabel R6 Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 5.38%
5 Years rr_AverageAnnualReturnYear05 2.81%
Since Inception rr_AverageAnnualReturnSinceInception 2.37%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | STRATEGIC INCOME FUND  
Prospectus: rr_ProspectusTable  
Risk/Return [Heading] rr_RiskReturnHeading Strategic Income Fund
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The fund seeks income.
Objective, Secondary [Text Block] rr_ObjectiveSecondaryTextBlock
As a secondary objective, the fund seeks long-term capital appreciation.
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, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 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 16 of the fund’s prospectus, Appendix A 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 88% of the average value of its portfolio.
Portfolio Turnover, Rate rr_PortfolioTurnoverRate 88.00%
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 $100,000 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 16 of the fund’s prospectus, Appendix A 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 $ 100,000
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 and that you earn a 5% return each year. The example also assumes that the fund’s operating expenses remain the same, except that it reflects the rate and duration of any fee waivers noted in the table above. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading] rr_StrategyHeading Principal Investment Strategies
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock
The fund invests in both investment-grade and high-yield, non-money market debt securities. These securities may include corporate bonds and notes, government securities and securities backed by mortgages or other assets. Investment grade securities are those that have been rated in one of the top four credit quality categories by an independent rating agency or determined by the advisor to be of comparable credit quality. High-yield securities, which are also known as “junk bonds”, are those that have been rated by an independent rating agency below the highest four categories or determined by the advisor to be of similar quality.
The debt securities in which the fund invests may be payable in U.S. or foreign currencies, including emerging markets debt securities.
The fund may also invest in certain equity securities such as preferred stock, convertible securities or equity equivalents provided that such investments are consistent with the fund’s investment objectives.
The fund may invest in securities issued or guaranteed by the U.S. Treasury and certain U.S. government agencies or instrumentalities such as the Government National Mortgage Association (Ginnie Mae). Ginnie Mae is supported by the full faith and credit of the U.S. government. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank (FHLB) are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, they are authorized to borrow from the U.S. Treasury to meet their obligations.
In addition to the securities listed above, the fund may also invest in bank loans.
The fund may also utilize derivative instruments provided that such investments are in keeping with the fund’s investment objectives. Such derivative instruments may include options, futures contracts, options on futures contracts, and swaps (such as credit default swaps either on a single issuer or a securities index), or in mortgage- or asset-backed securities. The fund may invest in collateralized debt obligations, including collateralized loan obligations, collateralized mortgage obligations, mortgage- or asset- backed securities, and other similarly structured investments. The fund may use foreign currency exchange contracts to shift investment exposure from one currency into another for hedging purposes or to enhance returns.
The weighted average maturity of the fund’s portfolio must be 3½ years or longer. Within this maturity limit, the portfolio managers may shorten the portfolio’s maturity during periods of rising interest rates in order to reduce the effect of bond price declines on the fund’s value.
To determine whether to buy or sell a security, the portfolio managers consider, among other things, various fund requirements and standards, along with economic conditions, alternative investments and interest rates.
The portfolio managers may engage in hedging of portfolio positions, which usually involves entering into a derivative transaction that has the opposite characteristic of the position being hedged. The net effect of these two positions is intended to reduce or eliminate the exposure created by the first position.
To gain exposure to certain segments of the fixed-income market, the fund may invest in other American Century funds (affiliated funds), unaffiliated funds, securities and other financial instruments.
Risk [Heading] rr_RiskHeading Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock
•
Interest Rate Risk – Investments in debt securities are sensitive to interest rate changes. Generally, the value of debt securities and the funds that hold them decline as interest rates rise. The fund is more susceptible to interest rate changes than funds that have a shorter-weighted average maturity, such as money market and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.
•
Credit Risk – The inability or perceived inability of a security’s issuer to make interest and principal payments may cause the value of the security to decrease. As a result the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect.
•
High-Yield Risk – Issuers of high-yield securities are more vulnerable to real or perceived economic changes (such as an economic downturn or a prolonged period of rising interest rates), political changes or adverse developments specific to an issuer. These factors may be more likely to cause an issuer of low quality bonds to default on its obligations.
•
LIBOR Transition Risk – The fund may invest in instruments that have variable or floating coupon rates based on the London Interbank Offered Rate (“LIBOR”). LIBOR is a benchmark interest rate intended to be representative of the rate at which certain major international banks lend to one another over short-terms. Due to allegations of manipulation, LIBOR will be phased out by the end of 2021. Uncertainty remains regarding a replacement rate or rates for LIBOR. The transition process may lead to increased volatility or illiquidity in markets for instruments that rely on LIBOR. This could result in a change to the value of such instruments or a change in the cost of temporary borrowing for the fund.
•
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. Derivatives can be highly illiquid and difficult to unwind or value, and changes in the value of a derivative held by the fund may not correlate with the value of the underlying instrument or the fund’s other investments.
•
Bank Loan Risk – The market for bank loans may not be highly liquid and the fund may have difficulty selling them. In connection with purchasing loan participations, the fund generally will have no right to enforce compliance by borrowers with loan terms nor any set off rights, and the fund may not benefit directly from any posted collateral. As a result, the fund may be subject to the credit risk of both the borrower and the lender selling the participation. Bank loan transactions may take more than seven days to settle, meaning that proceeds would be unavailable to make additional investments or meet redemptions.
•
Collateralized Debt Obligations Risk – Collateralized debt obligations and collateralized loan obligations (CLOs) are subject to credit, interest rate, valuation, and prepayment and extension risks. These securities also are subject to risk of default on the underlying asset, particularly during periods of economic downturn. The market value of CLOs may be affected by, among other things, changes in the market value of the underlying assets held by the CLO, changes in the distributions on the underlying assets, defaults and recoveries on the underlying assets, capital gains and losses on the underlying assets, prepayments on underlying assets and the availability, prices and interest rate of underlying assets.
•
Counterparty Risk – If the fund enters into financial contracts, the fund will be subject to the credit risk presented by the counterparties.
•
Liquidity Risk – During periods of market turbulence or unusually low trading activity, 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. In addition, when the market for certain investments is illiquid, the fund may be unable to achieve its desired level of exposure to a certain sector. Illiquid securities may be difficult to value. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments.
•
Prepayment Risk – The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds of similar maturity that invest less heavily in mortgage- and asset-backed securities.
•
Foreign Securities Risk – Foreign securities are generally riskier than U.S. securities. Political events (such as civil unrest, national elections and imposition of exchange controls), social and economic events (such as labor strikes and rising inflation), natural disasters and public health emergencies occurring in a country where the fund invests could cause the fund’s investments in that country to experience losses. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities.
•
Currency Risk – Because the fund may invest in securities denominated in foreign currencies, the fund could experience gains or losses based solely on changes in the exchange rate between foreign currencies and the U.S. dollar.
•
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.
•
Convertible Securities Risk – Convertible securities may be affected by changes in interest rates, the credit of the issuer, and the value of the underlying common stock. In addition, because these securities are convertible into common stock, they are subject to general stock market risk, though to a lesser degree.
•
Market Risk – The value of securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.
•
Redemption Risk – The fund may need to sell securities at times it would not otherwise do so to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.
•
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, 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 (1Q 2019): 4.74%    Lowest Performance Quarter (3Q 2015):-1.81%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 1.15%.
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns For the calendar year ended December 31, 2019
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.
Investment Trust Prospectus | STRATEGIC INCOME FUND | Bloomberg Barclays U.S Aggregate Bond Index  
Prospectus: rr_ProspectusTable  
Index No Deduction for Fees, Expenses, Taxes [Text] rr_IndexNoDeductionForFeesExpensesTaxes (reflects no deduction for fees, expenses or taxes)
Label rr_AverageAnnualReturnLabel Bloomberg Barclays U.S. Aggregate Bond Index    (reflects no deduction for fees, expenses or taxes)
1 Year rr_AverageAnnualReturnYear01 8.72%
5 Years rr_AverageAnnualReturnYear05 3.05%
Since Inception rr_AverageAnnualReturnSinceInception 3.17%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | STRATEGIC INCOME FUND | INVESTOR CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASIEX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee $ 25
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.74%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.05%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.80%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets (0.04%) [26]
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.76%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 78
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 243
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 423
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 943
Annual Return 2015 rr_AnnualReturn2015 (0.41%)
Annual Return 2016 rr_AnnualReturn2016 7.29%
Annual Return 2017 rr_AnnualReturn2017 6.00%
Annual Return 2018 rr_AnnualReturn2018 (1.65%)
Annual Return 2019 rr_AnnualReturn2019 9.77%
Year to Date Return, Label rr_YearToDateReturnLabel Investor Class year-to-date return
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2020
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn 1.15%
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Highest Performance Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Mar. 31, 2019
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 4.74%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Lowest Performance Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Sep. 30, 2015
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn (1.81%)
Label rr_AverageAnnualReturnLabel Investor Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 9.77%
5 Years rr_AverageAnnualReturnYear05 4.10%
Since Inception rr_AverageAnnualReturnSinceInception 3.65%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | STRATEGIC INCOME FUND | INVESTOR CLASS | After Taxes on Distributions  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions
1 Year rr_AverageAnnualReturnYear01 8.38%
5 Years rr_AverageAnnualReturnYear05 2.55%
Since Inception rr_AverageAnnualReturnSinceInception 2.07%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | STRATEGIC INCOME FUND | INVESTOR CLASS | After Taxes on Distributions and Sales  
Prospectus: rr_ProspectusTable  
Label rr_AverageAnnualReturnLabel Return After Taxes on Distributions and Sale of Fund Shares
1 Year rr_AverageAnnualReturnYear01 5.76%
5 Years rr_AverageAnnualReturnYear05 2.43%
Since Inception rr_AverageAnnualReturnSinceInception 2.06%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | STRATEGIC INCOME FUND | I CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASIGX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.64%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.05%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.70%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets (0.04%) [26]
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.66%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 68
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 212
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 368
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 823
Label rr_AverageAnnualReturnLabel I Class1 Return Before Taxes [27]
1 Year rr_AverageAnnualReturnYear01 9.88% [27]
5 Years rr_AverageAnnualReturnYear05 4.23% [27]
Since Inception rr_AverageAnnualReturnSinceInception 3.75% [27]
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 10, 2017 [27]
Investment Trust Prospectus | STRATEGIC INCOME FUND | Y CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASYIX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.54%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.05%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.60%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets (0.04%) [26]
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.56%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 57
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 180
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 313
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 702
Label rr_AverageAnnualReturnLabel Y Class1 Return Before Taxes [27]
1 Year rr_AverageAnnualReturnYear01 10.00% [27]
5 Years rr_AverageAnnualReturnYear05 4.33% [27]
Since Inception rr_AverageAnnualReturnSinceInception 3.86% [27]
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 10, 2017 [27]
Investment Trust Prospectus | STRATEGIC INCOME FUND | A CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASIQX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice 4.50%
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none [28]
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.74%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.05%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.05%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets (0.04%) [26]
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 1.01%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 549
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 758
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 983
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,631
Label rr_AverageAnnualReturnLabel A Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 4.59%
5 Years rr_AverageAnnualReturnYear05 2.91%
Since Inception rr_AverageAnnualReturnSinceInception 2.52%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | STRATEGIC INCOME FUND | C CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASIHX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther 1.00%
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.74%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 1.00%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.05%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.80%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets (0.04%) [26]
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 1.76%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 179
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 555
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 955
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 2,071
Label rr_AverageAnnualReturnLabel C Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 8.68%
5 Years rr_AverageAnnualReturnYear05 3.09%
Since Inception rr_AverageAnnualReturnSinceInception 2.62%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | STRATEGIC INCOME FUND | R CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASIWX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.74%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.50%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.05%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.30%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets (0.04%) [26]
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 1.26%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 129
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 400
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 692
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,522
Label rr_AverageAnnualReturnLabel R Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 9.33%
5 Years rr_AverageAnnualReturnYear05 3.63%
Since Inception rr_AverageAnnualReturnSinceInception 3.16%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | STRATEGIC INCOME FUND | R5 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASIJX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.54%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.05%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.60%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets (0.04%) [26]
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.56%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 57
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 180
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 313
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 702
Label rr_AverageAnnualReturnLabel R5 Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 9.98%
5 Years rr_AverageAnnualReturnYear05 4.33%
Since Inception rr_AverageAnnualReturnSinceInception 3.86%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | STRATEGIC INCOME FUND | R6 CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol ASIPX
Maximum Cumulative Sales Charge (as a percentage of Offering Price) rr_MaximumCumulativeSalesChargeOverOfferingPrice none
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.49%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Acquired Fund Fees and Expenses rr_AcquiredFundFeesAndExpensesOverAssets 0.05%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.55%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets (0.04%) [26]
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.51%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 52
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 164
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 286
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 641
Label rr_AverageAnnualReturnLabel R6 Class Return Before Taxes
1 Year rr_AverageAnnualReturnYear01 10.04%
5 Years rr_AverageAnnualReturnYear05 4.38%
Since Inception rr_AverageAnnualReturnSinceInception 3.91%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2014
Investment Trust Prospectus | U.S. GOVERNMENT MONEY MARKET FUND  
Prospectus: rr_ProspectusTable  
Risk/Return [Heading] rr_RiskReturnHeading U.S. Government Money Market Fund
Objective [Heading] rr_ObjectiveHeading Investment Objective
Objective, Primary [Text Block] rr_ObjectivePrimaryTextBlock
The fund seeks current income while maintaining liquidity and preserving capital.
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, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. More information about sales charges that may apply in certain circumstances where such shares were acquired by exchange from another American Century Investments fund, is available from your financial professional and in Calculation of Sales Charges on page 11 of the fund’s prospectus, Appendix A 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)
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. The example also assumes that the fund’s operating expenses remain the same, except that it reflects the rate and duration of any fee waivers noted in the table above. Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Strategy [Heading] rr_StrategyHeading Principal Investment Strategies
Strategy Narrative [Text Block] rr_StrategyNarrativeTextBlock
The fund is a government money market fund, which means it invests at least 99.5% of its total assets in cash, U.S. government securities, and/or repurchase agreements that are collateralized by government securities or cash. Additionally, the fund has a policy to invest at least 80% of its assets in government securities and/or repurchase agreements collateralized by government securities. Government securities include any securities issued or guaranteed as to principal or interest by the United States and its agencies or instrumentalities. The securities purchased by the fund are subject to the maturity, quality, diversification, and other requirements of Rule 2a-7 under the Investment Company Act of 1940, as amended. Thus, the fund invests its assets in high quality, very short term debt securities.
Because this fund is a government money market fund, both retail and institutional shareholders may invest in the fund. This fund does not have the ability to impose a liquidity fee on the sale of shares or temporarily suspend redemptions in response to decreases in liquidity.
Securities issued or guaranteed by the U.S. Treasury and certain U.S. government agencies or instrumentalities such as the Government National Mortgage Association (Ginnie Mae), are supported by the full faith and credit of the U.S. government. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), Federal Farm Credit Bank (FFCB), and the Federal Home Loan Bank (FHLB) are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, they are authorized to borrow from the U.S. Treasury to meet their obligations.
The fund may purchase government securities through buy/sell back transactions. The fund may commit up to 35% of its total assets to such transactions.
The securities in which the fund invests may include adjustable rate securities, such as variable rate demand notes (VRDNs).
Because short-term, U.S. government securities are among the safest securities available, the interest they pay is among the lowest for income-paying securities. Accordingly, the yield on this fund will likely be lower than the yield on funds that invest in longer-term or lower-quality securities.
To determine whether to buy or sell a security, the portfolio managers consider, among other things, various fund requirements and standards, along with economic conditions, alternative investments and interest rates.
Risk [Heading] rr_RiskHeading Principal Risks
Risk Narrative [Text Block] rr_RiskNarrativeTextBlock
Even though the fund’s investments are designed to minimize interest rate, liquidity and credit risk, the fund is still subject to some degree of risk.
•
Interest Rate Risk – Interest rate risk means that the value of debt securities and funds that hold them decline as interest rates rise. A sharp and unexpected rise in interest rates could cause the fund’s price to drop.
•
Liquidity Risk – Changing regulatory or market conditions, including increases in interest rates or credit spreads, may adversely affect the liquidity of the fund’s investments. During periods of market turbulence or unusually low trading activity, 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.
•
Credit Risk – Credit risk is the risk that the inability or perceived inability of the issuer to make interest and principal payments will cause the value of the securities to decrease.
•
Redemption Risk – The fund may need to sell securities at times it would not otherwise do so to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs or have tax consequences. To the extent that a large shareholder (including a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.
•
Repurchase Agreement Risk – If the seller in a repurchase agreement transaction defaults on its obligation to repurchase a security at a mutually agreed-upon time and price under the agreement, the fund may suffer delays and incur costs or lose money in exercising its rights under the agreement.
You could lose money by investing in the fund. Although the fund seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The fund’s sponsor has no legal obligation to provide financial support to the fund, and you should not expect that the sponsor will provide financial support to the fund at any time.
Risk Lose Money [Text] rr_RiskLoseMoney You could lose money by investing in the fund.
Risk Not Insured Depository Institution [Text] rr_RiskNotInsuredDepositoryInstitution An investment in the fund is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Bar Chart and Performance Table [Heading] rr_BarChartAndPerformanceTableHeading Fund Performance
Performance Narrative [Text Block] rr_PerformanceNarrativeTextBlock
The following bar chart and table provide some indication of the 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 fund’s past performance is not necessarily an indication of how the fund will perform in the future. On December 1, 2015, the fund changed its investment objective and strategy so that it would qualify as a government money market fund, as that term is defined in Rule 2a-7 of the Investment Company Act. Performance for periods before December 1, 2015 is based on the fund’s prior investment strategy. 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.
Performance Availability Website Address [Text] rr_PerformanceAvailabilityWebSiteAddress americancentury.com
Performance Past Does Not Indicate Future [Text] rr_PerformancePastDoesNotIndicateFuture The fund’s past performance 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 2019): 0.50%          Lowest Performance Quarter (2Q 2015): 0.00%

As of June 30, 2020, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 0.28%.
Performance Table Heading rr_PerformanceTableHeading Average Annual Total Returns For the calendar year ended December 31, 2019
Investment Trust Prospectus | U.S. GOVERNMENT MONEY MARKET FUND | INVESTOR CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol TCRXX
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee $ 25
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.45%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.46%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.46%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 47
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 148
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 258
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 580
Annual Return 2010 rr_AnnualReturn2010 0.01%
Annual Return 2011 rr_AnnualReturn2011 0.01%
Annual Return 2012 rr_AnnualReturn2012 0.01%
Annual Return 2013 rr_AnnualReturn2013 0.01%
Annual Return 2014 rr_AnnualReturn2014 0.01%
Annual Return 2015 rr_AnnualReturn2015 0.01%
Annual Return 2016 rr_AnnualReturn2016 0.03%
Annual Return 2017 rr_AnnualReturn2017 0.44%
Annual Return 2018 rr_AnnualReturn2018 1.41%
Annual Return 2019 rr_AnnualReturn2019 1.79%
Year to Date Return, Label rr_YearToDateReturnLabel year-to-date return
Bar Chart, Year to Date Return, Date rr_BarChartYearToDateReturnDate Jun. 30, 2020
Bar Chart, Year to Date Return rr_BarChartYearToDateReturn 0.28%
Highest Quarterly Return, Label rr_HighestQuarterlyReturnLabel Highest Performance Quarter
Highest Quarterly Return, Date rr_BarChartHighestQuarterlyReturnDate Jun. 30, 2019
Highest Quarterly Return rr_BarChartHighestQuarterlyReturn 0.50%
Lowest Quarterly Return, Label rr_LowestQuarterlyReturnLabel Lowest Performance Quarter
Lowest Quarterly Return, Date rr_BarChartLowestQuarterlyReturnDate Mar. 31, 2015
Lowest Quarterly Return rr_BarChartLowestQuarterlyReturn none
Label rr_AverageAnnualReturnLabel Investor Class
1 Year rr_AverageAnnualReturnYear01 1.79%
5 Years rr_AverageAnnualReturnYear05 0.73%
10 Years rr_AverageAnnualReturnYear10 0.37%
Inception Date rr_AverageAnnualReturnInceptionDate Apr. 01, 1993
Investment Trust Prospectus | U.S. GOVERNMENT MONEY MARKET FUND | A CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AGQXX
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none [29]
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.45%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.25%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.71%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.71%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 73
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 227
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 396
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 883
Label rr_AverageAnnualReturnLabel A Class
1 Year rr_AverageAnnualReturnYear01 1.53%
Since Inception rr_AverageAnnualReturnSinceInception 0.76%
Inception Date rr_AverageAnnualReturnInceptionDate Dec. 01, 2015
Investment Trust Prospectus | U.S. GOVERNMENT MONEY MARKET FUND | C CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AGHXX
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none [29]
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.45%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets 0.75%
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 1.21%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets none
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 1.21%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 124
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 385
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 666
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 1,465
Label rr_AverageAnnualReturnLabel C Class
1 Year rr_AverageAnnualReturnYear01 1.03%
Since Inception rr_AverageAnnualReturnSinceInception 0.49%
Inception Date rr_AverageAnnualReturnInceptionDate Dec. 01, 2015
Investment Trust Prospectus | U.S. GOVERNMENT MONEY MARKET FUND | G CLASS  
Prospectus: rr_ProspectusTable  
Trading Symbol dei_TradingSymbol AGGXX
Maximum Deferred Sales Charge (as a percentage) rr_MaximumDeferredSalesChargeOverOther none
Maximum Account Fee rr_MaximumAccountFee none
Management Fees (as a percentage of Assets) rr_ManagementFeesOverAssets 0.45%
Distribution and Service (12b-1) Fees rr_DistributionAndService12b1FeesOverAssets none
Other Expenses (as a percentage of Assets): rr_OtherExpensesOverAssets 0.01%
Expenses (as a percentage of Assets) rr_ExpensesOverAssets 0.46%
Fee Waiver or Reimbursement rr_FeeWaiverOrReimbursementOverAssets (0.45%) [30]
Net Expenses (as a percentage of Assets) rr_NetExpensesOverAssets 0.01%
Expense Example, with Redemption, 1 Year rr_ExpenseExampleYear01 $ 1
Expense Example, with Redemption, 3 Years rr_ExpenseExampleYear03 3
Expense Example, with Redemption, 5 Years rr_ExpenseExampleYear05 6
Expense Example, with Redemption, 10 Years rr_ExpenseExampleYear10 $ 13
Label rr_AverageAnnualReturnLabel G Class
1 Year rr_AverageAnnualReturnYear01 2.25%
Since Inception rr_AverageAnnualReturnSinceInception 1.88%
Inception Date rr_AverageAnnualReturnInceptionDate Jul. 28, 2017
[1] The management fee has been restated to reflect the decrease in the management fee schedule effective August 1, 2020.
[2] Historical performance for the I Class prior to its inception (April 10, 2017) is based on the performance of R5 Class shares. I Class performance has been adjusted to reflect differences in expenses between classes, if applicable.
[3] Purchases 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.
[4] The advisor agreed to waive the G Class’s management fee in its entirety. The advisor expects this waiver to remain in effect permanently and cannot terminate it without the approval of the Board of Trustees.
[5] Historical performance for the Y Class prior to its inception is based on the performance of R6 Class shares. Y Class performance has been adjusted to reflect differences in expenses between classes. Since inception performance for the Y Class is based on the R6 Class inception date.
[6] Purchases 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.
[7] Historical performance for the R5 Class prior to its inception is based on the performance of I Class shares, which have the same expenses as the R5 Class.
[8] Historical performance for the Investor, I, A and R5 Classes prior to their inception is based on the performance of the Predecessor Fund and Prior Predecessor Fund. Investor, I, A and R5 Class performance has been adjusted to reflect differences in sales charges, if applicable, and expenses between classes. Since inception performance is based on the inception date of the Predecessor Funds.
[9] Purchases 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.
[10] The management fee has been restated to reflect the decrease in the management fee schedule effective August 1, 2019.
[11] Historical performance for the I and Y Classes prior to their inception is based on the performance of R5 Class shares. I and Y Class performance has been adjusted to reflect differences in expenses between classes, if applicable.
[12] Purchases 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.
[13] The advisor has agreed to waive the G Class’s management fee in its entirety. The advisor expects this waiver to remain in effect permanently and cannot terminate it without the approval of the Board of Trustees.
[14] The management fee has been restated to reflect the decrease in the management fee schedule effective August 1, 2019.
[15] The advisor has agreed to waive the G Class’s management fee in its entirety. The advisor expects this waiver to remain in effect permanently and cannot terminate it without the approval of the Board of Trustees.
[16] Purchases in these shares may be subject to a contingent deferred sales charge (CDSC) of 1.00% for A and C Class in certain circumstances where such shares were acquired by exchange from another American Century Investments fund.
[17] Historical performance for the I Class prior to its inception is based on the performance of R5 Class shares. I Class performance has been adjusted to reflect differences in expenses between classes, if applicable.
[18] Purchases of $500,000 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.
[19] Historical performance for the I and Y Classes prior to their inception is based on the performance of R5 Class shares. I and Y Class performance has been adjusted to reflect differences in expenses between classes, if applicable.
[20] Purchases of $500,000 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.
[21] Prior to August 31, 2011, this class had a front-end sales charge of 4.50%. The front-end sales charge is now 2.25%. Performance prior to that date has been restated to reflect this change in the sales charge.
[22] The advisor has agreed to waive the G Class’s management fee in its entirety. The advisor expects this waiver to remain in effect permanently and cannot terminate it without the approval of the Board of Trustees.
[23] The management fee has been restated to reflect the decrease in the management fee schedule effective August 1, 2020.
[24] Historical performance for the I and Y Classes prior to their inception is based on the performance of R5 Class shares. I and Y Class performance has been adjusted to reflect differences in expenses between classes, if applicable. Since inception performance for the I and Y Class is based on the R5 Class inception date.
[25] Purchases of $500,000 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.
[26] The advisor will waive the portion of the fund’s management fee equal to the expenses attributable to the management fees of the American Century funds in which the fund invests. The amount of this waiver fluctuates depending on the fund’s daily allocation to other American Century funds. This waiver is expected to remain in effect permanently and it cannot be terminated without the approval of the Board of Trustees.
[27] Historical performance for the I and Y Classes prior to their inception is based on the performance of R5 Class shares. I and Y Class performance has been adjusted to reflect differences in expenses between classes, if applicable. Since inception performance for the I and Y Class is based on the R5 Class inception date.
[28] Purchases 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.
[29] Purchases in these shares may be subject to a contingent deferred sales charge (CDSC) of 1.00% for A and C Class in certain circumstances where such shares were acquired by exchange from another American Century Investments fund.
[30] The advisor has agreed to waive the G Class’s management fee in its entirety. The advisor expects this waiver to remain in effect permanently and cannot terminate it without the approval of the Board of Trustees.