Label	Element	Value
Risk Return [Abstract]	rr_RiskReturnAbstract
ProspectusDate	rr_ProspectusDate	Oct. 01, 2012
American Funds Tax-Exempt Fund of New York (Prospectus Summary) | American Funds Tax-Exempt Fund of New York
Risk Return [Abstract]	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	American Funds Tax-Exempt Fund of New York®
Objective [Heading]	rr_ObjectiveHeading	Investment objectives
Objective, Primary [Text Block]	rr_ObjectivePrimaryTextBlock	The fund's primary investment objective is to provide you with a high level of current income exempt from regular federal, New York state and New York City income taxes.
Objective, Secondary [Text Block]	rr_ObjectiveSecondaryTextBlock	Its secondary objective is preservation of capital.
Expense [Heading]	rr_ExpenseHeading	Fees and expenses of the fund
Expense Narrative [Text Block]	rr_ExpenseNarrativeTextBlock	This table describes the fees and expenses that you may pay if you buy and hold shares of the fund. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in American Funds. More information about these and other discounts is available from your financial professional and in the "Sales charge reductions and waivers" section on page 48 of the prospectus and on page 70 of the fund's statement of additional information.
Shareholder Fees Caption [Text]	rr_ShareholderFeesCaption	Shareholder fees (fees paid directly from your investment)
Operating Expenses Caption [Text]	rr_OperatingExpensesCaption	Annual fund operating expenses (expenses that you pay each year as a percentage of the value of your investment)
Portfolio Turnover [Heading]	rr_PortfolioTurnoverHeading	Portfolio turnover
Portfolio Turnover [Text Block]	rr_PortfolioTurnoverTextBlock	The fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund's investment results. During the most recent fiscal year, the fund's portfolio turnover rate was 15% of the average value of its portfolio.
Portfolio Turnover, Rate	rr_PortfolioTurnoverRate	15.00%
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 Funds.
Expense Breakpoint, Minimum Investment Required [Amount]	rr_ExpenseBreakpointMinimumInvestmentRequiredAmount	100,000
Expense Example [Heading]	rr_ExpenseExampleHeading	Example
Expense Example Narrative [Text Block]	rr_ExpenseExampleNarrativeTextBlock	This example is intended to help you compare the cost of investing in the fund with the cost of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods. The example also assumes that your investment has a 5% return each year and that the fund's operating expenses remain the same.
Expense Example by, Year, Caption [Text]	rr_ExpenseExampleByYearCaption	Although your actual costs may be higher or lower, based on these assumptions your costs would be:
Expense Example, No Redemption, By Year, Caption [Text]	rr_ExpenseExampleNoRedemptionByYearCaption	For the share classes listed below, you would pay the following if you did not redeem your shares:
Strategy [Heading]	rr_StrategyHeading	Principal investment strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The fund seeks to achieve its objectives by primarily investing in municipal bonds issued by the state of New York and its agencies and municipalities. Consistent with the fund's objectives, the fund may also invest in municipal securities that are issued by jurisdictions outside New York. Municipal bonds are debt obligations generally issued to obtain funds for various public purposes, including the construction of public facilities. Under normal circumstances, the fund will invest at least 80% of its assets in, or derive at least 80% of its income from, securities that are exempt from regular federal, New York state and New York City income taxes and that do not subject you to federal alternative minimum tax. The fund may also invest up to 20% of its assets in securities that subject you to federal alternative minimum tax. The fund is intended primarily for taxable residents of New York. The fund will invest primarily in debt securities rated BBB- or better or Baa3 or better by Nationally Recognized Statistical Rating Organizations designated by the fund's investment adviser, or unrated but determined by the fund's investment adviser to be of equivalent quality. The fund also may invest in debt securities rated BB+ or below and Ba1 or below by Nationally Recognized Statistical Rating Organizations designated by the fund's investment adviser, or unrated but determined by the fund's investment adviser to be of equivalent quality. Such securities are sometimes referred to as "junk bonds." Some of the securities held by the fund may have credit and liquidity support features, including guarantees and letters of credit. The investment adviser uses a system of multiple portfolio counselors in managing the fund's assets. Under this approach, the portfolio of the fund is divided into segments managed by individual counselors who decide how their respective segments will be invested. The fund relies on the professional judgment of its investment adviser to make decisions about the fund's portfolio investments. The basic investment philosophy of the investment adviser is to seek to invest in attractively priced securities that, in its opinion, represent good, long-term investment opportunities. The investment adviser believes that an important way to accomplish this is by analyzing various factors, which may include the credit strength of the issuer, prices of similar securities issued by comparable issuers, anticipated changes in interest rates, general market conditions and other factors pertinent to the particular security being evaluated. Securities may be sold when the investment adviser believes that they no longer represent relatively attractive investment opportunities.
Risk [Heading]	rr_RiskHeading	Principal risks
Risk Narrative [Text Block]	rr_RiskNarrativeTextBlock	This section describes the principal risks associated with the fund's principal investment strategies. You may lose money by investing in the fund. The likelihood of loss may be greater if you invest for a shorter period of time. Risks of investing in municipal bonds of issuers within the state of New York - Because the fund invests primarily in securities of issuers within the state of New York, the fund is more susceptible to factors adversely affecting issuers of New York securities than a comparable municipal bond mutual fund that does not concentrate in a single state. For example, such factors may include political policy changes, tax base erosion, state constitutional limits on tax increases, budget deficits and other financial or economic difficulties, and changes in the credit ratings assigned to New York's municipal issuers. New York's economy and finances may be especially vulnerable to changes in the performance of the financial services sector, which historically has been volatile. More detailed information about the risks of investing in New York municipal securities is contained in the statement of additional information. Market conditions -- The prices of, and the income generated by, the securities held by the fund may decline due to market conditions and other factors, including those directly involving the issuers of securities held by the fund. Investing in bonds -- Rising interest rates will generally cause the prices of bonds and other debt securities to fall. Longer maturity debt securities may be subject to greater price fluctuations than shorter maturity debt securities. In addition, falling interest rates may cause an issuer to redeem, call or refinance a security before its stated maturity, which may result in the fund having to reinvest the proceeds in lower yielding securities. Bonds and other debt securities are subject to credit risk, which is the possibility that the credit strength of an issuer will weaken and/or an issuer of a debt security will fail to make timely payments of principal or interest and the security will go into default. Thinly traded securities -- There may be little trading in the secondary market for particular bonds or other debt securities, which may make them more difficult to value, acquire or sell. Credit and liquidity support -- Changes in the credit quality of banks and financial institutions providing credit and liquidity support features with respect to securities held by the fund could cause the values of these securities to decline. Investing in lower rated bonds -- Lower rated bonds and other lower rated debt securities generally have higher rates of interest and involve greater risk of default or price declines due to changes in the issuer's creditworthiness than those of higher quality debt securities. The market prices of these securities may fluctuate more than the prices of higher quality debt securities and may decline significantly in periods of general economic difficulty. These risks may be increased with respect to investments in junk bonds. Investing in similar municipal bonds -- Investing significantly in municipal obligations of issuers in the same state or backed by revenues of similar types of projects or industries may make the fund more susceptible to certain economic, political or regulatory occurrences. As a result, the potential for fluctuations in the fund's share price may increase. Management -- The investment adviser to the fund actively manages the fund's investments. Consequently, the fund is subject to the risk that the methods and analyses employed by the investment adviser in this process may not produce the desired results. This could cause the fund to lose value or its investment results to lag relevant benchmarks or other funds with similar objectives. Your investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency, entity or person. You should consider how this fund fits into your overall investment program.
Risk Lose Money [Text]	rr_RiskLoseMoney	You may lose money by investing in the fund.
Risk Not Insured Depository Institution [Text]	rr_RiskNotInsuredDepositoryInstitution	Your investment in the fund is not a bank deposit and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other governmental agency, entity or person.
Bar Chart and Performance Table [Heading]	rr_BarChartAndPerformanceTableHeading	Investment results
Performance Narrative [Text Block]	rr_PerformanceNarrativeTextBlock	The following bar chart shows the fund's investment results for its first full calendar year of operations, and the following table shows the fund's average annual total returns for various periods compare with different broad measures of market results. This information provides some indication of the risks of investing in the fund. The Lipper New York Municipal Debt Funds Average includes the fund and other funds that disclose investment objectives and/or strategies reasonably comparable to the fund's objective and/or strategies. Past investment results (before and after taxes) are not predictive of future investment results. Updated information on the fund's investment results can be obtained by visiting americanfunds.com.
Performance Information Illustrates Variability of Returns [Text]	rr_PerformanceInformationIllustratesVariabilityOfReturns	The following bar chart shows the fund's investment results for its first full calendar year of operations, and the following table shows the fund's average annual total returns for various periods compare with different broad measures of market results.
Performance Additional Market Index [Text]	rr_PerformanceAdditionalMarketIndex	The Lipper New York Municipal Debt Funds Average includes the fund and other funds that disclose investment objectives and/or strategies reasonably comparable to the fund's objective and/or strategies.
Performance Availability Website Address [Text]	rr_PerformanceAvailabilityWebSiteAddress	americanfunds.com
Performance Past Does Not Indicate Future [Text]	rr_PerformancePastDoesNotIndicateFuture	Past investment results (before and after taxes) are not predictive of future investment results.
Bar Chart [Heading]	rr_BarChartHeading	Calendar year total returns for Class A shares (Results do not include a sales charge; if a sales charge were included, results would be lower.)
Bar Chart Narrative [Text Block]	rr_BarChartNarrativeTextBlock	The following bar chart shows the fund's investment results for its first full calendar year of operations, and the following table shows the fund's average annual total returns for various periods compare with different broad measures of market results.
Bar Chart Does Not Reflect Sales Loads [Text]	rr_BarChartDoesNotReflectSalesLoads	(Results do not include a sales charge; if a sales charge were included, results would be lower.)
Bar Chart Closing [Text Block]	rr_BarChartClosingTextBlock	Highest/Lowest quarterly results during the period were: Highest 3.99% (quarter ended September 30, 2011) Lowest 0.62% (quarter ended March 31, 2011) The fund's total return for the six months ended June 30, 2012, was 4.49%.
Performance Table Uses Highest Federal Rate	rr_PerformanceTableUsesHighestFederalRate	After-tax returns are calculated using the highest individual federal income tax rates in effect during each year of the periods shown and do not reflect the impact of state and local taxes.
Performance Table Not Relevant to Tax Deferred	rr_PerformanceTableNotRelevantToTaxDeferred	Your actual after-tax returns depend on your individual tax situation and likely will differ from the results shown above.
Performance Table One Class of after Tax Shown [Text]	rr_PerformanceTableOneClassOfAfterTaxShown	After-tax returns are shown only for Class A shares; after-tax returns for other share classes will vary.
Performance Table Narrative	rr_PerformanceTableNarrativeTextBlock	After-tax returns are shown only for Class A shares; after-tax returns for other share classes will vary. After-tax returns are calculated using the highest individual federal income tax rates in effect during each year of the periods shown and do not reflect the impact of state and local taxes. Your actual after-tax returns depend on your individual tax situation and likely will differ from the results shown above.
Performance Table Footnotes	rr_PerformanceTableFootnotesTextBlock	Class A annualized 30-day yield at July 31, 2012: 2.30%          (For current yield information, please call American FundsLine® at 800/325-3590.)
Caption	rr_AverageAnnualReturnCaption	Average annual total returns For the periods ended December 31, 2011 (with maximum sales charge):
American Funds Tax-Exempt Fund of New York (Prospectus Summary) | American Funds Tax-Exempt Fund of New York | Barclays New York Municipal Funds Index
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Barclays New York Municipal Funds Index (reflects no deductions for sales charges, account fees, expenses or taxes)
1 Year	rr_AverageAnnualReturnYear01	9.79%
5 Years	rr_AverageAnnualReturnYear05	5.26%
Since Inception	rr_AverageAnnualReturnSinceInception	5.05%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 01, 2010
American Funds Tax-Exempt Fund of New York (Prospectus Summary) | American Funds Tax-Exempt Fund of New York | Lipper New York Municipal Debt Funds Average
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Lipper New York Municipal Debt Funds Average (reflects no deductions for sales charges, account fees or taxes)
1 Year	rr_AverageAnnualReturnYear01	9.69%
5 Years	rr_AverageAnnualReturnYear05	3.79%
10 Years	rr_AverageAnnualReturnYear10	4.47%
Since Inception	rr_AverageAnnualReturnSinceInception	3.90%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 01, 2010
American Funds Tax-Exempt Fund of New York (Prospectus Summary) | American Funds Tax-Exempt Fund of New York | Class A
Risk Return [Abstract]	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	3.75%
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	1.00%	[1]
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFeeOverRedemption	none
Management fees	rr_ManagementFeesOverAssets	0.38%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.18%
Other expenses	rr_OtherExpensesOverAssets	0.20%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.76%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.13%)	[2]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	0.63%
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	2013-09-30
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	437
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	596
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	769
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,270
Annual Return 2011	rr_AnnualReturn2011	10.92%
Highest Quarterly Return, Label	rr_HighestQuarterlyReturnLabel	Highest
Highest Quarterly Return, Date	rr_BarChartHighestQuarterlyReturnDate	Sep. 30, 2011
Highest Quarterly Return	rr_BarChartHighestQuarterlyReturn	3.99%
Lowest Quarterly Return, Label	rr_LowestQuarterlyReturnLabel	Lowest
Lowest Quarterly Return, Date	rr_BarChartLowestQuarterlyReturnDate	Mar. 31, 2011
Lowest Quarterly Return	rr_BarChartLowestQuarterlyReturn	0.62%
Label	rr_AverageAnnualReturnLabel	Share class A - Before taxes
1 Year	rr_AverageAnnualReturnYear01	6.72%
Since Inception	rr_AverageAnnualReturnSinceInception	2.69%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 01, 2010
Thirty Day Yield Caption	rr_ThirtyDayYieldCaption	Class A annualized 30-day yield at July 31, 2012:
Thirty Day Yield Phone	rr_ThirtyDayYieldPhone	800/325-3590
Thirty Day Yield	rr_ThirtyDayYield	2.30%
American Funds Tax-Exempt Fund of New York (Prospectus Summary) | American Funds Tax-Exempt Fund of New York | Class A | After Taxes on Distributions
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Share class A - After taxes on distributions
1 Year	rr_AverageAnnualReturnYear01	6.72%
Since Inception	rr_AverageAnnualReturnSinceInception	2.69%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 01, 2010
American Funds Tax-Exempt Fund of New York (Prospectus Summary) | American Funds Tax-Exempt Fund of New York | Class A | After Taxes on Distributions and Sales
Risk Return [Abstract]	rr_RiskReturnAbstract
Label	rr_AverageAnnualReturnLabel	Share class A - After taxes on distributions and sale of fund shares
1 Year	rr_AverageAnnualReturnYear01	5.48%
Since Inception	rr_AverageAnnualReturnSinceInception	2.71%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 01, 2010
American Funds Tax-Exempt Fund of New York (Prospectus Summary) | American Funds Tax-Exempt Fund of New York | Class B
Risk Return [Abstract]	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	5.00%
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFeeOverRedemption	none
Management fees	rr_ManagementFeesOverAssets	0.38%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.99%
Other expenses	rr_OtherExpensesOverAssets	0.22%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.59%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.14%)	[2]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	1.45%
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	2013-09-30
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	648
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	888
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	1,052
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,654
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	148
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	488
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	852
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	1,654
Label	rr_AverageAnnualReturnLabel	Share class B - Before taxes
1 Year	rr_AverageAnnualReturnYear01	4.95%
Since Inception	rr_AverageAnnualReturnSinceInception	1.81%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 01, 2010
American Funds Tax-Exempt Fund of New York (Prospectus Summary) | American Funds Tax-Exempt Fund of New York | Class C
Risk Return [Abstract]	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	1.00%
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFeeOverRedemption	none
Management fees	rr_ManagementFeesOverAssets	0.38%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	1.00%
Other expenses	rr_OtherExpensesOverAssets	0.24%
Total annual fund operating expenses	rr_ExpensesOverAssets	1.62%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.12%)	[2]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	1.50%
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	2013-09-30
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	253
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	499
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	870
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,912
Expense Example, No Redemption, 1 Year	rr_ExpenseExampleNoRedemptionYear01	153
Expense Example, No Redemption, 3 Years	rr_ExpenseExampleNoRedemptionYear03	499
Expense Example, No Redemption, 5 Years	rr_ExpenseExampleNoRedemptionYear05	870
Expense Example, No Redemption, 10 Years	rr_ExpenseExampleNoRedemptionYear10	1,912
Label	rr_AverageAnnualReturnLabel	Share class C - Before taxes
1 Year	rr_AverageAnnualReturnYear01	8.89%
Since Inception	rr_AverageAnnualReturnSinceInception	5.23%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 01, 2010
American Funds Tax-Exempt Fund of New York (Prospectus Summary) | American Funds Tax-Exempt Fund of New York | Class F-1
Risk Return [Abstract]	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFeeOverRedemption	none
Management fees	rr_ManagementFeesOverAssets	0.38%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	0.23%
Other expenses	rr_OtherExpensesOverAssets	0.25%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.86%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.11%)	[2]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	0.75%
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	2013-09-30
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	77
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	263
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	466
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	1,051
Label	rr_AverageAnnualReturnLabel	Share class F-1 - Before taxes
1 Year	rr_AverageAnnualReturnYear01	10.70%
Since Inception	rr_AverageAnnualReturnSinceInception	5.95%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 01, 2010
American Funds Tax-Exempt Fund of New York (Prospectus Summary) | American Funds Tax-Exempt Fund of New York | Class F-2
Risk Return [Abstract]	rr_RiskReturnAbstract
Maximum sales charge (load) imposed on purchases (as a percentage of offering price)	rr_MaximumSalesChargeImposedOnPurchasesOverOfferingPrice	none
Maximum deferred sales charge (load) (as a percentage of the amount redeemed)	rr_MaximumDeferredSalesChargeOverOfferingPrice	none
Maximum sales charge (load) imposed on reinvested dividends	rr_MaximumSalesChargeOnReinvestedDividendsAndDistributionsOverOther	none
Redemption or exchange fees	rr_RedemptionFeeOverRedemption	none
Management fees	rr_ManagementFeesOverAssets	0.38%
Distribution and/or service (12b-1) fees	rr_DistributionAndService12b1FeesOverAssets	none
Other expenses	rr_OtherExpensesOverAssets	0.25%
Total annual fund operating expenses	rr_ExpensesOverAssets	0.63%
Expense reimbursement	rr_FeeWaiverOrReimbursementOverAssets	(0.10%)	[2]
Total annual fund operating expenses after expense reimbursement	rr_NetExpensesOverAssets	0.53%
Fee Waiver or Reimbursement over Assets, Date of Termination	rr_FeeWaiverOrReimbursementOverAssetsDateOfTermination	2013-09-30
Expense Example, with Redemption, 1 Year	rr_ExpenseExampleYear01	54
Expense Example, with Redemption, 3 Years	rr_ExpenseExampleYear03	192
Expense Example, with Redemption, 5 Years	rr_ExpenseExampleYear05	341
Expense Example, with Redemption, 10 Years	rr_ExpenseExampleYear10	777
Label	rr_AverageAnnualReturnLabel	Share class F-2 - Before taxes
1 Year	rr_AverageAnnualReturnYear01	10.98%
Since Inception	rr_AverageAnnualReturnSinceInception	6.20%
Inception Date	rr_AverageAnnualReturnInceptionDate	Nov. 01, 2010

[1] A contingent deferred sales charge of 1.00% applies on certain redemptions made within one year following purchases of $1 million or more made without an initial sales charge.

[2] The investment adviser is currently reimbursing a portion of the other expenses. The reimbursement will be in effect at least through September 30, 2013, unless modified or terminated by the fund's board. The adviser may elect at its discretion to extend, modify or terminate the reimbursement at that time.