2.2.0.25truefalse0030 - Statement - CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY AND COMPREHENSIVE INCOMEtruefalseIn Thousandsfalse1falsefalseUSDtruefalse{us-gaap_PartnerCapitalComponentsAxis} : Partners' Capital 1/1/2010 - 12/31/2010 USD ($) $D2010_PartnerCapitalMemberhttp://www.sec.gov/CIK0001166036na0001-01-01T00:00:000001-01-01T00:00:00falsefalsemwe_PartnerCapitalMemberus-gaap_PartnerCapitalComponentsAxisxbrldihttp://xbrl.org/2006/xbrldimwe_PartnerCapitalMemberus-gaap_PartnerCapitalComponentsAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2falsefalseUSDtruefalse{us-gaap_PartnerCapitalComponentsAxis} : Accumulated Other Comprehensive Income 1/1/2008 - 12/31/2008 USD ($) $D2008_AccumulatedOtherComprehensiveIncomeMemberhttp://www.sec.gov/CIK0001166036na0001-01-01T00:00:000001-01-01T00:00:00falsefalseus-gaap_AccumulatedOtherComprehensiveIncomeMemberus-gaap_PartnerCapitalComponentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_AccumulatedOtherComprehensiveIncomeMemberus-gaap_PartnerCapitalComponentsAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3falsefalseUSDtruefalse{us-gaap_PartnerCapitalComponentsAxis} : Non-controlling Interest 1/1/2010 - 12/31/2010 USD ($) $D2010_NoncontrollingInterestMemberhttp://www.sec.gov/CIK0001166036na0001-01-01T00:00:000001-01-01T00:00:00falsefalseus-gaap_NoncontrollingInterestMemberus-gaap_PartnerCapitalComponentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_NoncontrollingInterestMemberus-gaap_PartnerCapitalComponentsAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4falsefalseUSDtruefalse{us-gaap_PartnerCapitalComponentsAxis} : Comprehensive Income 1/1/2008 - 12/31/2008 USD ($) $D2008_ComprehensiveIncomeMemberhttp://www.sec.gov/CIK0001166036na0001-01-01T00:00:000001-01-01T00:00:00falsefalseus-gaap_ComprehensiveIncomeMemberus-gaap_PartnerCapitalComponentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ComprehensiveIncomeMemberus-gaap_PartnerCapitalComponentsAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$5falsefalseUSDfalsefalse1/1/2010 - 12/31/2010 USD ($) USD ($) / shares $D2010http://www.sec.gov/CIK0001166036na0001-01-01T00:00:000001-01-01T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDPerShareDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$1false0us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestus-gaaptruecreditinstantNo definition available.falsefalsefalsetruefalsefalsefalsetruefalsefalseperiodstartlabelinstant2008-01-01T00:00:000001-01-01T00:00:001truefalsefalse3846300038463falsetruefalsetruefalse2truefalsefalse928000928falsetruefalsetruefalse3truefalsefalse524583000524583falsetruefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse563974000563974falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal of Stockholders' Equity (deficit) items, net of receivables from officers, directors owners, and affiliates of the entity including portions attributable to both the parent and noncontrolling interests (previously referred to as minority interest), if any. The entity including portions attributable to the parent and noncontrolling interests is sometimes referred to as the economic entity. This excludes temporary equity and is sometimes called permanent equity.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 25 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 26 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A3 -Appendix A falsefalseBalance at Dec. 31, 20072false0us-gaap_LimitedPartnersCapitalAccountUnitsOutstandingus-gaaptruenainstantNo definition available.falsefalsefalsetruefalsefalsefalsetruefalsefalseperiodstartlabelinstant2008-01-01T00:00:000001-01-01T00:00:001truefalsefalse2286100022861falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsefalsefalseSharesxbrli:sharesItemTypesharesThe number of limited partner units outstanding. The limited partners are partners of a publicly traded limited partnership or master limited partnership. Limited partners have limited liability and do not manage the partnership.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section F Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Practice Bulletin (PB) -Number 14 -Paragraph 10 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 falsefalseBalance (in units) at Dec. 31, 20073true0us-gaap_IncreaseDecreaseInPartnersCapitalRollForwardus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringA roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.falsefalseIncrease (Decrease) in Equity4false0us-gaap_PartnersCapitalAccountOptionExerciseus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse375000375falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse375000375falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal change in each class of partners' capital accounts during the year due to option exercise. All partners include general, limited and preferred partners.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Practice Bulletin (PB) -Number 14 -Paragraph 15 falsefalseOption exercises5false0mwe_PartnersCapitalAccountOptionExerciseUnitsmwefalsenadurationNumber of units issued upon exercise of an option.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse9800098falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsefalsefalseSharesxbrli:sharesItemTypesharesNumber of units issued upon exercise of an option.No authoritative reference available.falsefalseOption exercises (in units)6false0us-gaap_PartnersCapitalAccountUnitBasedCompensationus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse1156000011560falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse1156000011560falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal change in each class of partners' capital accounts during the year due to unit-based compensation. All partners include general, limited and preferred partners.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Practice Bulletin (PB) -Number 14 -Paragraph 15 falsefalseShare-based compensation activity7false0us-gaap_PartnersCapitalAccountUnitsUnitbasedCompensationus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse1400014falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsefalsefalseSharesxbrli:sharesItemTypesharesThe number of units issued due to unit-based compensation.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Practice Bulletin (PB) -Number 14 -Paragraph 15 falsefalseShare-based compensation activity (in units)8false0us-gaap_PaymentsOfDividendsCommonStockus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse-4338000-4338falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse-4338000-4338falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe cash outflow from the distribution of an entity's earnings in the form of dividends to common shareholders.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph a falsefalseDividends paid9false0us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensationus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse717000717falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse717000717falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTax benefit associated with any share-based compensation plan other than an employee stock ownership plan (ESOP). The tax benefit results from the deduction by the entity on its tax return for an award of stock that exceeds the cumulative compensation cost for common stock or preferred stock recognized for financial reporting. Includes any resulting tax benefit that exceeds the previously recognized deferred tax asset (excess tax benefits).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph 62 falsefalseExcess tax benefits related to share-based compensation10false0us-gaap_PaymentsOfCapitalDistributionus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse-107269000-107269falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3truefalsefalse-19651000-19651falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse-126920000-126920falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe cash outflow from any dividend or other distribution in cash with respect to any shares of, or other ownership interest in, an entity, except a dividend consisting of distribution of earnings or stock dividend or pro rata stock split.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph a falsefalseDistributions paid11false0mwe_MinorityInterestIncreaseFromPartialAcquisitonmwefalsecreditdurationIncrease in noncontrolling interest balance due to the acquisition of a less than 100 percent interest in an entity that is...falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3truefalsefalse29350002935falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse29350002935falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryIncrease in noncontrolling interest balance due to the acquisition of a less than 100 percent interest in an entity that is consolidated.No authoritative reference available.falsefalseAcquisition of partially owned entity included as part of PQ Gathering Assets, L.L.C.12false0us-gaap_PartnersCapitalOtherus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3truefalsefalse10320001032falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse10320001032falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThis element represents movements included in the statement of changes in partners' capital which are not separately disclosed or provided for elsewhere in the taxonomy.No authoritative reference available.falsefalseOther13false0us-gaap_PartnersCapitalAccountRedemptionsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1truefalsefalse-240513000-240513falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse-240513000-240513falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal change in each class of partners' capital accounts during the year due to redemptions and adjustments to redemption value. All partners include general, limited and preferred partners.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Practice Bulletin (PB) -Number 14 -Paragraph 15 falsefalseRedemption of MarkWest Hydrocarbon, Inc. common stock14false0us-gaap_PartnersCapitalAccountUnitsRedeemedus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1truefalsefalse-7458000-7458falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsefalsefalseSharesxbrli:sharesItemTypesharesThe number of units redeemed during the year of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners of a publicly listed limited partnership or a master limited partnership. This may include units of general, limited, and preferred partners of a publicly listed limited partnership of a master limited partnership. General partners have unlimited liability and manage the partnership. Limited partners have limited liability and do not manage the partnership.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Practice Bulletin (PB) -Number 14 -Paragraph 15 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 16 -Subparagraph a, b -Article 6 falsefalseRedemption of MarkWest Hydrocarbon, Inc. common stock (in units)15false0mwe_PartnersCapitalAccountUnitConversionmwefalsenadurationNumber of units issued upon conversion of restricted shares as a result of the Merger.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse-45000-45falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsefalsefalseSharesxbrli:sharesItemTypesharesNumber of units issued upon conversion of restricted shares as a result of the Merger.No authoritative reference available.falsefalseConversion of restricted stock to phantom units in connection with the Merger (in units)16false0mwe_PartnersCapitalAcquisitionOfGeneralPartnershipInterestmwefalsecreditdurationIncrease in partners' capital due to the acquisition of general partnership's noncontrolling interest.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse3007800030078falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse3007800030078falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryIncrease in partners' capital due to the acquisition of general partnership's noncontrolling interest.No authoritative reference available.falsefalseAcquisition of General Partnership's non-controlling interest associated with the Merger17false0mwe_PartnersCapitalAcquisitionofGeneralPartnershipInterestInUnitsmwefalsenadurationNumber of units issued upon the acquisition of general partnership's noncontrolling interest.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse946000946falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsefalsefalseSharesxbrli:sharesItemTypesharesNumber of units issued upon the acquisition of general partnership's noncontrolling interest.No authoritative reference available.falsefalseAcquisition of General Partnership's non-controlling interest associated with the Merger (in units)18false0mwe_EquityChangesFromPurchaseOfNoncontrollingInterestmwefalsecreditdurationChange in equity due to the purchase of the interests of noncontrolling shareholders.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse10959170001095917falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3truefalsefalse-502297000-502297falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse593620000593620falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryChange in equity due to the purchase of the interests of noncontrolling shareholders.No authoritative reference available.falsefalsePurchase of non-controlling interest of MarkWest Energy Partners, L.P.19false0mwe_EquityChangesFromPurchaseofNoncontrollingInterestInUnitsmwefalsenadurationNumber of units issued upon purchase of non-controlling interest.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse3447400034474falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsefalsefalseSharesxbrli:sharesItemTypesharesNumber of units issued upon purchase of non-controlling interest.No authoritative reference available.falsefalsePurchase of non-controlling interest of MarkWest Energy Partners, L.P. (in units)20false0us-gaap_PartnersCapitalAccountPublicSaleOfUnitsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse171395000171395falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse171395000171395falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryMonetary value of the issuance of new units of limited partnership interest in a public offering.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 falsefalseIssuance of units in public offering, net of offering costs21false0us-gaap_PartnersCapitalAccountUnitsSoldInPublicOfferingus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse57500005750falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsefalsefalseSharesxbrli:sharesItemTypesharesThe number of units sold in a public offering of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners of a publicly listed limited partnership or a master limited partnership. This may include units of general, limited, and preferred partners of a publicly listed limited partnership or a master limited partnership. General partners have unlimited liability and manage the partnership. Limited partners have limited liability and do not manage the partnership.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Practice Bulletin (PB) -Number 14 -Paragraph 15 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 16 -Subparagraph a, b -Article 6 falsefalseIssuance of units in public offering, net of offering costs (in units)22false0us-gaap_ProfitLossus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse208073000208073falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3truefalsefalse-3301000-3301falsefalsefalsetruefalse4truefalsefalse204772000204772falsefalsefalsetruefalse5truefalsefalse204772000204772falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A1, A4, A5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 5 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 29 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(1) falsefalseNet income (loss)23false0us-gaap_OtherComprehensiveIncomeReclassificationAdjustmentForSaleOfSecuritiesIncludedInNetIncomeNetOfTaxus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1falsefalsefalse00falsefalsefalsetruefalse2truefalsefalse-928000-928falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4truefalsefalse-928000-928falsefalsefalsetruefalse5truefalsefalse-928000-928falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryReclassification adjustment for unrealized gains or losses realized upon the sale of securities, after tax.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(3) Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 24 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 18, 19 falsefalseRealized gain on marketable securities, net of tax of $55824false0us-gaap_ComprehensiveIncomeNetOfTaxus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4truefalsefalse203844000203844falsefalsefalsetruefalse5truefalsefalse203844000203844falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A5 -Appendix A Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 30 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(3) Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 8, 9, 10, 11, 12, 13, 14 truefalseComprehensive income25false0us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestus-gaaptruecreditinstantNo definition available.falsefalsefalsetruefalsefalsefalsefalsetruefalseperiodendlabelinstant2008-12-31T00:00:000001-01-01T00:00:001truefalsefalse12044580001204458falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3truefalsefalse33010003301falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse12077590001207759falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal of Stockholders' Equity (deficit) items, net of receivables from officers, directors owners, and affiliates of the entity including portions attributable to both the parent and noncontrolling interests (previously referred to as minority interest), if any. The entity including portions attributable to the parent and noncontrolling interests is sometimes referred to as the economic entity. This excludes temporary equity and is sometimes called permanent equity.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 25 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 26 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A3 -Appendix A falsefalseBalance at Dec. 31, 200826false0us-gaap_LimitedPartnersCapitalAccountUnitsOutstandingus-gaaptruenainstantNo definition available.falsefalsefalsetruefalsefalsefalsefalsetruefalseperiodendlabelinstant2008-12-31T00:00:000001-01-01T00:00:001truefalsefalse5664000056640falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsefalsefalseSharesxbrli:sharesItemTypesharesThe number of limited partner units outstanding. The limited partners are partners of a publicly traded limited partnership or master limited partnership. Limited partners have limited liability and do not manage the partnership.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section F Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Practice Bulletin (PB) -Number 14 -Paragraph 10 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 falsefalseBalance (in units) at Dec. 31, 200827true0us-gaap_IncreaseDecreaseInPartnersCapitalRollForwardus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1falsefalsefalse00falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringA roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.falsefalseIncrease (Decrease) in Equity28false0us-gaap_PartnersCapitalAccountUnitBasedCompensationus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse52040005204falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse52040005204falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal change in each class of partners' capital accounts during the year due to unit-based compensation. 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available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse-118668000-118668falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3truefalsefalse53140005314falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse-113354000-113354falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A1, A4, A5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 5 -Subparagraph b Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 29 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(1) falsefalseNet income (loss)37false0us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestus-gaaptruecreditinstantNo definition available.falsefalsefalsetruefalsefalsefalsefalsetruefalseperiodendlabelinstant2009-12-31T00:00:000001-01-01T00:00:001truefalsefalse10966540001096654falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3truefalsefalse282739000282739falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse13793930001379393falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal of Stockholders' Equity (deficit) items, net of receivables from officers, directors owners, and affiliates of the entity including portions attributable to both the parent and 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This excludes temporary equity and is sometimes called permanent equity.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 25 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 26 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A3 -Appendix A falsefalseBalance at Dec. 31, 200938false0us-gaap_LimitedPartnersCapitalAccountUnitsOutstandingus-gaaptruenainstantNo definition available.falsefalsefalsetruefalsefalsefalsefalsetruefalseperiodendlabelinstant2009-12-31T00:00:000001-01-01T00:00:001truefalsefalse6627500066275falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse6627500066275falsefalsefalsefalsefalseSharesxbrli:sharesItemTypesharesThe number of limited partner units outstanding. 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All partners include general, limited and preferred partners.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Practice Bulletin (PB) -Number 14 -Paragraph 15 falsefalseShare-based compensation activity41false0us-gaap_PartnersCapitalAccountUnitsUnitbasedCompensationus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse278000278falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsefalsefalseSharesxbrli:sharesItemTypesharesThe number of units issued due to unit-based compensation.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Practice Bulletin (PB) -Number 14 -Paragraph 15 falsefalseShare-based compensation activity (in units)42false0us-gaap_AdjustmentsToAdditionalPaidInCapitalTaxEffectFromShareBasedCompensationus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse9800098falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse9800098falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTax benefit associated with any share-based compensation plan other than an employee stock ownership plan (ESOP). The tax benefit results from the deduction by the entity on its tax return for an award of stock that exceeds the cumulative compensation cost for common stock or preferred stock recognized for financial reporting. Includes any resulting tax benefit that exceeds the previously recognized deferred tax asset (excess tax benefits).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 123R -Paragraph 62 falsefalseExcess tax benefits related to share-based compensation43false0us-gaap_PaymentsOfCapitalDistributionus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse-181058000-181058falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3truefalsefalse-6150000-6150falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse-187208000-187208falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe cash outflow from any dividend or other distribution in cash with respect to any shares of, or other ownership interest in, an entity, except a dividend consisting of distribution of earnings or stock dividend or pro rata stock split.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 18 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 20 -Subparagraph a falsefalseDistributions paid44false0us-gaap_PartnersCapitalAccountPublicSaleOfUnitsus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse142255000142255falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5truefalsefalse142255000142255falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryMonetary value of the issuance of new units of limited partnership interest in a public offering.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 falsefalseIssuance of units in public offering, net of offering costs45false0us-gaap_PartnersCapitalAccountUnitsSoldInPublicOfferingus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse48870004887falsefalsefalsetruefalse2falsefalsefalse00falsefalsefalsetruefalse3falsefalsefalse00falsefalsefalsetruefalse4falsefalsefalse00falsefalsefalsetruefalse5falsefalsefalse00falsefalsefalsefalsefalseSharesxbrli:sharesItemTypesharesThe number of units sold in a public offering of each class of partners' capital account. 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