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This element includes paid and unpaid dividends declared during the period.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 AICPA -Name Statement of Position (SOP) -Number 01-6 -Paragraph 14 -Subparagraph l falsefalseIn-kind distributions6false0us-gaap_PartnersCapitalAccountDistributionsus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse-38435000-38435falsefalsefalsefalsefalse2truefalsefalse-31905000-31905falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryTotal distributions to each class of partners (i.e., 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 falsefalseCash distributions to common unitholders7false0cpno_IssuanceOfUnitscpnofalsecreditinstantThe value of units sold of each class of unit. 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Partners include general, limited and preferred partners. Limited liability partnerships (LLPs) are formed in accordance with the laws of the state in which such entities are organized. Because those laws are not uniform, the characteristics of LPCs vary from state to state. 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Units represent shares of ownership of the 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. 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Preferred units represent ownership of a public limited liability company.No authoritative reference available.falsefalseAccrued in-kind units20false0us-gaap_DividendsPreferredStockPaidinkindus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse-7880000-7880falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryDividend to be paid-in-kind declared for preferred shareholders by an entity during the period. 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Units represent shares of ownership of the general, limited, and preferred partners of a publicly listed limited partnership or a master limited partnership. The partners' capital account includes general, limited and preferred partners. General partners have unlimited liability and manage the partnership. 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Units represent ownership of a public limited liability company. 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However, LLPs generally have the following characteristics: An LLP is an unincorporated association of two or more "persons"; Its members have limited personal liability for the obligations or debts of the entity; It is classified as a partnership for federal income tax purposes.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 falsefalseEnding Balance56false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://copanoenergy.com/role/statementconsolidatedstatementofmemberscapitalandcomprehensiveincomelossunaudited1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse13falsefalseUSDtruefalse{us-gaap_StatementEquityComponentsAxis} : Comprehensive Income [Member] 1/1/2011 - 3/31/2011 USD ($) $FROM_Jan01_2011_TO_Mar31_2011_us-gaap_StatementEquityComponentsAxis_ComprehensiveIncomeMemberhttp://www.sec.gov/CIK0001297067duration2011-01-01T00:00:002011-03-31T00:00:00falsefalseComprehensive Income [Member]us-gaap_StatementEquityComponentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ComprehensiveIncomeMemberus-gaap_StatementEquityComponentsAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$14falsefalseUSDtruefalse{us-gaap_StatementEquityComponentsAxis} : Comprehensive Income [Member] 1/1/2010 - 3/31/2010 USD ($) $FROM_Jan01_2010_TO_Mar31_2010_us-gaap_StatementEquityComponentsAxis_ComprehensiveIncomeMemberhttp://www.sec.gov/CIK0001297067duration2010-01-01T00:00:002010-03-31T00:00:00falsefalseComprehensive Income [Member]us-gaap_StatementEquityComponentsAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ComprehensiveIncomeMemberus-gaap_StatementEquityComponentsAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseComprehensive Income [Member]57false0us-gaap_NetIncomeLossus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse35320003532falsefalsefalsefalsefalse2truefalsefalse-1260000-1260falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 19 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph d Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A7 -Appendix A 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 SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 20 -Article 9 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 10, 15 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Emerging Issues Task Force (EITF) -Number 87-21 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28, 29, 30 falsefalseNet loss58false0us-gaap_OtherComprehensiveIncomeReclassificationAdjustmentOnDerivativesIncludedInNetIncomeNetOfTaxus-gaaptruedebitdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsetruenegated1truefalsefalse83820008382falsefalsefalsefalsefalse2truefalsefalse855000855falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryNet of tax effect of the reclassification adjustment for accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges included in accumulated comprehensive income that was realized in net income during the period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 18, 19 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph c(3) Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 24 -Subparagraph b Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 31, 46 falsefalseDerivative settlements reclassified to income59false0us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTaxus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse-15649000-15649falsefalsefalsefalsefalse2truefalsefalse566000566falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryChange in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges, net of tax effect. The after tax effect change includes an entity's share of an equity investee's increase (decrease) in deferred hedging gains or losses.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 17, 20 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 121 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 FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 24 -Subparagraph b Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 46 truefalseUnrealized gain-change in fair value of derivatives60false0us-gaap_ComprehensiveIncomeNetOfTaxus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalsetotallabel1truefalsefalse-3735000-3735falsetruefalsefalsefalse2truefalsefalse161000161falsetruefalsefalsefalseMonetaryxbrli: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 loss259Consolidated Statement of Members Capital and Comprehensive Income (Loss) (Unaudited) (USD $)ThousandsThousandsUnKnownUnKnownfalsetrue