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Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=16385135&loc=d3e33749-111570 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 18 -Paragraph 19 -Subparagraph c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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. Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.12) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 11 -Article 7 false2Equity in income (loss) of affiliates55false 5us-gaap_EquityMethodInvestmentsus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse17000001700USD$falsefalsefalse2truefalsefalse16000001600USD$falsefalsefalse3truefalsefalse17000001700USD$falsefalsefalse4truefalsefalse16000001600USD$falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. 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All considered to be "operating revenue" for purposes of the taxonomy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (a),(b),(c) -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8736-108599 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph a, b, c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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. false2Total revenues59false 5ahgp_SegmentAdjustedEbitdaExpenseahgp_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-3914000-3914[2]USD$falsefalsefalse2truefalsefalse-5702000-5702[2]USD$falsefalsefalse3truefalsefalse-7471000-7471[2]USD$falsefalsefalse4truefalsefalse-9805000-9805[2]USD$falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetarySegment Adjusted EBITDA Expense includes operating expenses, outside coal purchases and other income. Transportation expenses are excluded.No definition available.false2Segment Adjusted EBITDA Expense60false 5ahgp_SegmentAdjustedEbitdaahgp_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2truefalsefalse-85000-85[3],[4]USD$falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetarySegment Adjusted EBITDA is defined as net income (prior to the allocation of noncontrolling interest) before income taxes, net interest expense, depreciation, depletion and amortization, and general and administrative expenses.No definition available.false2Segment Adjusted EBITDA61false 5us-gaap_Assetsus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse-936000-936[5]USD$falsetruefalse2truefalsefalse-2560000-2560[5]USD$falsetruefalse3truefalsefalse-936000-936[5]USD$falsetruefalse4truefalsefalse-2560000-2560[5]USD$falsetruefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetarySum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 18 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.18) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 12 -Article 7 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Concepts (CON) -Number 6 -Paragraph 25 -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. false2Total assets1Revenues included in the Other and Corporate column are primarily attributable to the Matrix Group revenues, Mt. Vernon transloading revenues and brokerage sales.2Segment Adjusted EBITDA Expense includes operating expenses, outside coal purchases and other income. Transportation expenses are excluded as these expenses are passed through to the ARLP Partnership's customers and consequently it does not realize any gain or loss on transportation revenues. We review Segment Adjusted EBITDA Expense per ton for cost trends.3Includes equity in income (loss) of affiliates for the three and six months ended June 30, 2013 of $(5.9) million and $(10.1) million, respectively, included in the White Oak segment and $0.2 million and $0.5 million, respectively, included in the Other and Corporate segment. Includes equity in income (loss) of affiliates for the three and six months ended June 30, 2012 of $(4.6) million and $(8.6) million, respectively, included in the White Oak segment and $0.2 million and $0.4 million, respectively, included in the Other and Corporate segment.4Segment Adjusted EBITDA is defined as net income (prior to the allocation of noncontrolling interest) before income taxes, net interest expense, depreciation, depletion and amortization and general and administrative expenses. Management therefore is able to focus solely on the evaluation of segment operating profitability as it relates to the ARLP Partnership's revenues and operating expenses, which are primarily controlled by our segments.5Total assets for the White Oak and Other and Corporate Segments include investments in affiliate of $127.2 million and $1.7 million, respectively, at June 30, 2013 and $62.3 million and $1.6 million, respectively, at June 30, 2012.6Capital expenditures shown above include funding to White Oak of $6.8 million and $18.9 million, respectively, for the three and six months ended June 30, 2013, and $16.6 million and $34.6 million, respectively, for the three and six months ended June 30, 2012, for the acquisition and development of coal reserves in our condensed consolidated statements of cash flow.falseSEGMENT INFORMATION (Details) (USD $)ThousandsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.ahgp.com/role/DisclosureSegmentInformationDetails561