2.4.0.8100350 - Disclosure - Summarized Financial Information for Reportable Segments (Parenthetical) (Detail)truefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$C_0001483096_us-gaapStatementBusinessSegmentsAxis_acmpMarcellusShaleMember_20130401_20130630http://www.sec.gov/CIK0001483096duration2013-04-01T00:00:002013-06-30T00:00:00U_iso4217USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$C_0001483096_us-gaapStatementBusinessSegmentsAxis_acmpMarcellusShaleMember_20120401_20120630http://www.sec.gov/CIK0001483096duration2012-04-01T00:00:002012-06-30T00:00:00U_iso4217USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3false USDfalsefalse$C_0001483096_us-gaapStatementBusinessSegmentsAxis_acmpMarcellusShaleMember_20130101_20130630http://www.sec.gov/CIK0001483096duration2013-01-01T00:00:002013-06-30T00:00:00U_iso4217USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4false USDfalsefalse$C_0001483096_us-gaapStatementBusinessSegmentsAxis_acmpMarcellusShaleMember_20120101_20120630http://www.sec.gov/CIK0001483096duration2012-01-01T00:00:002012-06-30T00:00:00U_iso4217USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse1false USDtruefalse$C_0001483096_us-gaapStatementBusinessSegmentsAxis_acmpMarcellusShaleMember_20130401_20130630http://www.sec.gov/CIK0001483096duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseMarcellusus-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_MarcellusShaleMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberU_iso4217USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Marcellus2true 3acmp_SegmentReportingDisclosureLineItemsacmp_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Segment Reporting Disclosure [Line Items]3false 4us-gaap_AdditionsToNoncurrentAssetsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse50005[1]USD$falsetruefalse2falsefalsefalse00  [2]USD$falsefalsefalse3truefalsefalse189000189[3]USD$falsetruefalse4falsefalsefalse00  [4]USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTotal expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Capital expenditures4false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5false USDtruefalse$C_0001483096_us-gaapStatementBusinessSegmentsAxis_acmpMarcellusShaleMember_us-gaapStatementEquityComponentsAxis_acmpInvestmentsInUnconsolidatedAffiliatesMember_20130401_20130630http://www.sec.gov/CIK0001483096duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseMarcellusus-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_MarcellusShaleMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberfalsefalseInvestments in Unconsolidated Affiliatesus-gaap_StatementEquityComponentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_InvestmentsInUnconsolidatedAffiliatesMemberus-gaap_StatementEquityComponentsAxisexplicitMemberU_iso4217USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Marcellus | Investments in Unconsolidated Affiliates5true 3acmp_SegmentReportingDisclosureLineItemsacmp_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Segment Reporting Disclosure [Line Items]6false 4us-gaap_AdditionsToNoncurrentAssetsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse7590000075900USD$falsefalsefalse2truefalsefalse9380000093800USD$falsefalsefalse3truefalsefalse169100000169100USD$falsefalsefalse4truefalsefalse175200000175200USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTotal expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Capital expenditures7false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse9false USDtruefalse$C_0001483096_us-gaapStatementBusinessSegmentsAxis_acmpNiobraraMember_20130401_20130630http://www.sec.gov/CIK0001483096duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseNiobraraus-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_NiobraraMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberU_iso4217USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Niobrara8true 3acmp_SegmentReportingDisclosureLineItemsacmp_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Segment Reporting Disclosure [Line Items]9false 4us-gaap_AdditionsToNoncurrentAssetsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse1167100011671[5]USD$falsefalsefalse2falsefalsefalse00  USD$falsefalsefalse3truefalsefalse2319700023197[6]USD$falsefalsefalse4falsefalsefalse00  USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTotal expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Capital expenditures10false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse13false USDtruefalse$C_0001483096_us-gaapStatementBusinessSegmentsAxis_acmpNiobraraMember_us-gaapStatementEquityComponentsAxis_acmpAttributableToNoncontrollingInterestMember_20130401_20130630http://www.sec.gov/CIK0001483096duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseNiobraraus-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_NiobraraMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberfalsefalseAttributable To Noncontrolling Interest Ownersus-gaap_StatementEquityComponentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_AttributableToNoncontrollingInterestMemberus-gaap_StatementEquityComponentsAxisexplicitMemberU_iso4217USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Niobrara | Attributable To Noncontrolling Interest Owners11true 3acmp_SegmentReportingDisclosureLineItemsacmp_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Segment Reporting Disclosure [Line Items]12false 4us-gaap_AdditionsToNoncurrentAssetsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse58000005800USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse1160000011600USD$falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryTotal expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Capital expenditures13false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse15false USDtruefalse$C_0001483096_us-gaapStatementBusinessSegmentsAxis_acmpUticaMember_20130401_20130630http://www.sec.gov/CIK0001483096duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseUticaus-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_UticaMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberU_iso4217USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Utica14true 3acmp_SegmentReportingDisclosureLineItemsacmp_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Segment Reporting Disclosure [Line Items]15false 4us-gaap_AdditionsToNoncurrentAssetsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse9402300094023[7]USD$falsefalsefalse2falsefalsefalse00  USD$falsefalsefalse3truefalsefalse165359000165359[8]USD$falsefalsefalse4falsefalsefalse00  USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTotal expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Capital expenditures16false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse19false USDtruefalse$C_0001483096_us-gaapStatementBusinessSegmentsAxis_acmpUticaMember_us-gaapStatementEquityComponentsAxis_acmpInvestmentsInUnconsolidatedAffiliatesMember_20130401_20130630http://www.sec.gov/CIK0001483096duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseUticaus-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_UticaMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberfalsefalseInvestments in Unconsolidated Affiliatesus-gaap_StatementEquityComponentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_InvestmentsInUnconsolidatedAffiliatesMemberus-gaap_StatementEquityComponentsAxisexplicitMemberU_iso4217USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Utica | Investments in Unconsolidated Affiliates17true 3acmp_SegmentReportingDisclosureLineItemsacmp_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Segment Reporting Disclosure [Line Items]18false 4us-gaap_AdditionsToNoncurrentAssetsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse112000000112000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse184000000184000USD$falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryTotal expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Capital expenditures19false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse21false USDtruefalse$C_0001483096_us-gaapStatementBusinessSegmentsAxis_acmpUticaMember_us-gaapStatementEquityComponentsAxis_acmpAttributableToNoncontrollingInterestMember_20130401_20130630http://www.sec.gov/CIK0001483096duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseUticaus-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_UticaMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberfalsefalseAttributable To Noncontrolling Interest Ownersus-gaap_StatementEquityComponentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_AttributableToNoncontrollingInterestMemberus-gaap_StatementEquityComponentsAxisexplicitMemberU_iso4217USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Utica | Attributable To Noncontrolling Interest Owners20true 3acmp_SegmentReportingDisclosureLineItemsacmp_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Segment Reporting Disclosure [Line Items]21false 4us-gaap_AdditionsToNoncurrentAssetsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse3380000033800USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse5580000055800USD$falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryTotal expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Capital expenditures22false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse23false USDtruefalse$C_0001483096_us-gaapStatementBusinessSegmentsAxis_acmpMidContinentAreaMember_20130401_20130630http://www.sec.gov/CIK0001483096duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseMid-Continentus-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_MidContinentAreaMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberU_iso4217USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Mid-Continent23true 3acmp_SegmentReportingDisclosureLineItemsacmp_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Segment Reporting Disclosure [Line Items]24false 4us-gaap_AdditionsToNoncurrentAssetsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse2913400029134[9]USD$falsefalsefalse2truefalsefalse3202900032029USD$falsefalsefalse3truefalsefalse6813000068130[10]USD$falsefalsefalse4truefalsefalse5469600054696USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTotal expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Capital expenditures25false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse27false USDtruefalse$C_0001483096_us-gaapStatementBusinessSegmentsAxis_acmpMidContinentAreaMember_us-gaapStatementEquityComponentsAxis_acmpInvestmentsInUnconsolidatedAffiliatesMember_20130401_20130630http://www.sec.gov/CIK0001483096duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseMid-Continentus-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_MidContinentAreaMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberfalsefalseInvestments in Unconsolidated Affiliatesus-gaap_StatementEquityComponentsAxisxbrldihttp://xbrl.org/2006/xbrldiacmp_InvestmentsInUnconsolidatedAffiliatesMemberus-gaap_StatementEquityComponentsAxisexplicitMemberU_iso4217USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Mid-Continent | Investments in Unconsolidated Affiliates26true 3acmp_SegmentReportingDisclosureLineItemsacmp_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Segment Reporting Disclosure [Line Items]27false 4us-gaap_AdditionsToNoncurrentAssetsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse23000002300USD$falsetruefalse2falsefalsefalse00falsefalsefalse3truefalsefalse26000002600USD$falsetruefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryTotal expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Capital expenditures1Amount excludes $75.9 million for the Partnership’s share of capital expenditures included in investments in unconsolidated affiliates.2Amount excludes $93.8 million for the Partnership’s share of capital expenditures included in investments in unconsolidated affiliates.3Amount excludes $169.1 million for the Partnership’s share of capital expenditures included in investments in unconsolidated affiliates.4Amount excludes $175.2 million for the Partnership’s share of capital expenditures included in investments in unconsolidated affiliates.5Amount includes $5.8 million of capital expenditures attributable to noncontrolling interest owners.6Amount includes $11.6 million of capital expenditures attributable to noncontrolling interest owners.7Amount excludes $112.0 million for the Partnership’s share of capital expenditures included in investments in unconsolidated affiliates and includes $33.8 million of capital expenditures attributable to noncontrolling interest owners.8Amount excludes $184.0 million for the Partnership’s share of capital expenditures included in investments in unconsolidated affiliates and includes $55.8 million of capital expenditures attributable to noncontrolling interest owners.9Amount excludes $2.3 million for the Partnership’s share of capital expenditures included in investments in unconsolidated affiliates.10Amount excludes $2.6 million for the Partnership’s share of capital expenditures included in investments in unconsolidated affiliates.falseSummarized Financial Information for Reportable Segments (Parenthetical) (Detail) (USD $)ThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.accessmidstream.com/20130630/taxonomy/role/DisclosureSummarizedFinancialInformationForReportableSegmentsParentheticalDetail427