2.4.0.801004 - Disclosure - Risk/Return Detail Data (American Beacon Stephens Mid-Cap Growth Fund) {Elements}truetruefalse1false falsefalseContext1http://www.sec.gov/CIK0000809593duration2013-06-20T00:00:002013-06-20T00:00:001true 2rr_RiskReturnAbstractrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Risk/Return:2false 3dei_EntityCentralIndexKeydei_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse000000809593falsefalsefalsedei:centralIndexKeyItemTypenaA unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation 12B -Number 240 -Section 12b -Subsection 1 false0Entity Central Index Key3false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2false truefalseContext2http://www.sec.gov/CIK0000809593duration2013-06-20T00:00:002013-06-20T00:00:00falsefalseAmerican Beacon Stephens Mid-Cap Growth Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldick0000809593_SummaryS000035896Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseAmerican Beacon Stephens Mid-Cap Growth Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldick0000809593_S000035896Memberdei_LegalEntityAxisexplicitMembernanafalse0American Beacon Stephens Mid-Cap Growth Fund | American Beacon Stephens Mid-Cap Growth Fund4true 2rr_RiskReturnAbstractrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Risk/Return:5false 3rr_RiskReturnHeadingrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00American Beacon Stephens Mid-Cap Growth Fundfalsefalsefalsexbrli:stringItemTypestringRisk/Return Summary Investment Objectives/Goals Include the following information, in plain English under rule 421(d) under the Securities Act, in the order and subject matter indicatedReference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 2 false0Risk/Return [Heading]6false 3ck0000809593_SupplementTextBlockck0000809593_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00American Beacon Stephens Mid-Cap Growth Fund Supplement Dated June 20, 2013 To the Prospectus dated March 28, 2013       The information below supplements the Prospectus dated March 28, 2013, and is in addition to any other supplements.   In the “Fees and Expenses of the Fund” section, footnote 2 in the Annual Fund Operating Expenses table is replaced with the following:   2 The Manager has contractually agreed to reduce and/or reimburse the A Class, C Class, Y Class, Institutional Class, and Investor Class of the Fund for Other Expenses through April 30, 2014 to the extent that Total Annual Fund Operating Expenses for the Fund exceed 1.49%, 2.24%, 1.09%, 0.99% and 1.37% for the A Class, C Class, Y Class, Institutional Class, and Investor Class, respectively (excluding taxes, brokerage commissions, acquired fund fees and expenses and other extraordinary expenses such as litigation). The contractual expense arrangement can be changed by approval of a majority of the Fund's Board of Trustees. The Manager can be reimbursed by the Fund for any contractual or voluntary fee reductions or expense reimbursements if reimbursement to the Manager (a) occurs within three years after the Manager's own reduction or reimbursement and (b) does not cause the Total Annual Fund Operating Expenses of a class to exceed the percentage limit contractually agreed.   In the “Fund Performance” section, the bar chart is deleted and replaced with the following:  falsefalsefalsenonnum:textBlockItemTypenaRisk/Return Supplement [Text Block]No definition available.false0Supplement [Text Block]7false 3rr_BarChartHeadingrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00Total Return for the Calendar Year Ended 12/31 of each Yearfalsefalsefalsexbrli:stringItemTypestringRisk/Return Bar Chart and Table.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 false0Bar Chart [Heading]8false 3ck0000809593_SupplementClosingTextBlockck0000809593_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00PLEASE RETAIN THIS SUPPLEMENT FOR FUTURE REFERENCEfalsefalsefalsexbrli:stringItemTypestringThere is no definition for this tag.No definition available.false0Supplement Closing [Text Block]9false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse3false truefalseContext3http://www.sec.gov/CIK0000809593duration2013-06-20T00:00:002013-06-20T00:00:00falsefalseAmerican Beacon Stephens Mid-Cap Growth Funddei_DocumentInformationDocumentAxisxbrldihttp://xbrl.org/2006/xbrldick0000809593_SummaryS000035896Memberdei_DocumentInformationDocumentAxisexplicitMemberfalsefalseAmerican Beacon Stephens Mid-Cap Growth Funddei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldick0000809593_S000035896Memberdei_LegalEntityAxisexplicitMemberfalsefalseInvestor Classrr_ProspectusShareClassAxisxbrldihttp://xbrl.org/2006/xbrldick0000809593_C000110031Memberrr_ProspectusShareClassAxisexplicitMemberUnit3Standardhttp://www.xbrl.org/2003/instancepurexbrli0nanafalse0American Beacon Stephens Mid-Cap Growth Fund | American Beacon Stephens Mid-Cap Growth Fund | Investor Class10true 2rr_RiskReturnAbstractrr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Risk/Return:11false 3rr_AnnualReturn2007rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.24440.2444falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 200712false 3rr_AnnualReturn2008rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse-0.4589-0.4589falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 200813false 3rr_AnnualReturn2009rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.39940.3994falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 200914false 3rr_AnnualReturn2010rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.27890.2789falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 201015false 3rr_AnnualReturn2011rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.02450.0245falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph instructions -Clause 3 -Exhibit a false0Annual Return 201116false 3rr_AnnualReturn2012rr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.14750.1475falsefalsefalsexbrli:pureItemTypepureIf the Fund has annual returns for at least one calendar year, provide a bar chart showing the Fund's annual total returns for each of the last 10 calendar years (or for the life of the Fund if less than 10 years), but only for periods subsequent to the effective date of the Fund's registration statement. Present the corresponding numerical return adjacent to each bar. If the Fund's fiscal year is other than a calendar year, include the year-to-date return information as of the end of the most recent quarter in a footnote to the bar chart. Following the bar chart, disclose the Fund's highest and lowest return for a quarter during the 10 years or other period of the bar chart. When a Multiple Class Fund offers more than one Class in the prospectus, provide annual total returns in the bar chart for only one of those Classes. The Fund can select which Class to include (e.g., the oldest Class, the Class with the greatest net assets).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Form -Number N-1A -Chapter A -Section 4 -Subsection b -Paragraph 2 -Subparagraph ii false0Annual Return 2012falseRisk/Return Detail Data (American Beacon Stephens Mid-Cap Growth Fund)UnKnownUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.americanbeaconfund.com/role/RRDetailData4116