2.2.0.7 false CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (unaudited) (USD $) 004000 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (unaudited) true false In Millions false false 1 USD false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 2 USD false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 3 USD false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ false 4 USD false false u000 Standard http://www.xbrl.org/2003/iso4217 USD iso4217 0 u002 Divide http://www.xbrl.org/2003/iso4217 USD iso4217 http://www.xbrl.org/2003/instance shares xbrli 0 u001 Standard http://www.xbrl.org/2003/instance shares xbrli 0 $ 2 CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS 0 us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract us-gaap true na duration No definition available. false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 3 Net loss 1 us-gaap_ProfitLoss us-gaap true credit duration No definition available. false false false false false false false false false false false false 1 true true false false -191000000 -191 false false false 2 true true false false -346000000 -346 false false false 3 true true false false -46000000 -46 false false false 4 true true false false -683000000 -683 false false false xbrli:monetaryItemType monetary The 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) false 4 Cash flow hedging activities, net: 1 us-gaap_OtherComprehensiveIncomeDerivativesQualifyingAsHedgesNetOfTaxPortionAttributableToParentAbstract us-gaap true na duration No definition available. false false false false false true false false false false false false 1 false false false false 0 0 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:stringItemType string No definition available. false 5 Unrealized mark-to-market gains arising during period, net 2 us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodNetOfTax us-gaap true credit duration No definition available. false false false false false false false false false false false false 1 false true false false 0 0 false false false 2 false true false false 81000000 81 false false false 3 false true false false 0 0 false false false 4 false true false false 115000000 115 false false false xbrli:monetaryItemType monetary Change 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 false 6 Deferred losses on cash flow hedges, net 2 us-gaap_OtherComprehensiveIncomeReclassificationAdjustmentOnDerivativesIncludedInNetIncomeNetOfTax us-gaap true debit duration No definition available. false false false false false false false false false false true negated false 1 false true false false 0 0 false false false 2 false true false false -3000000 -3 false false false 3 false true false false 0 0 false false false 4 false true false false -6000000 -6 false false false xbrli:monetaryItemType monetary Net 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 false 7 Changes in cash flow hedging activities, net (net of tax expense of zero, $7, zero and $16, respectively) 2 dyn_ChangesInCashFlowHedgingActivitiesNet dyn false credit duration Change in value of derivatives designated as cash flow hedges recorded to Other Comprehensive Income. false false false false false false false false false false false terselabel false 1 false true false false 0 0 false false false 2 false true false false 78000000 78 false false false 3 false true false false 0 0 false false false 4 false true false false 109000000 109 false false false xbrli:monetaryItemType monetary Change in value of derivatives designated as cash flow hedges recorded to Other Comprehensive Income. No authoritative reference available. false 8 Amortization of unrecognized prior service cost and actuarial gain (net of tax (expense) benefit of $(1), $2, $(1) and $(1), respectively) 1 us-gaap_OtherComprehensiveIncomeAmortizationOfDefinedBenefitPlanNetPriorServiceCostRecognizedInNetPeriodicPensionCostNetOfTax us-gaap true credit duration No definition available. false false false false false false false false false false false false 1 false true false false 0 0 false false false 2 false true false false 3000000 3 false false false 3 false true false false 2000000 2 false false false 4 false true false false 2000000 2 false false false xbrli:monetaryItemType monetary The adjustment out of other comprehensive income for prior service costs recognized as a component of net period benefit cost during the period, after tax. Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 158 -Paragraph 4 -Subparagraph c, d Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 106 -Paragraph 52 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 158 -Paragraph 7 -Subparagraph a Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 130 -Paragraph 17, 19, 24 false 9 Unconsolidated investments other comprehensive income, net (net of tax expense of zero, $2, zero and $4, respectively) 1 dyn_UnconsolidatedInvestmentsOtherComprehensiveLossNetOfTaxExpense dyn false na duration The change in other comprehensive income relating to unconsolidated investments. false false false false false false false false false false false terselabel false 1 false true false false 0 0 false false false 2 false true false false 5000000 5 false false false 3 false true false false 0 0 false false false 4 false true false false 6000000 6 false false false xbrli:monetaryItemType monetary The change in other comprehensive income relating to unconsolidated investments. No authoritative reference available. false 10 Other comprehensive income, net of tax 1 us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecrease us-gaap true na duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false 0 0 false false false 2 false true false false 86000000 86 false false false 3 false true false false 2000000 2 false false false 4 false true false false 117000000 117 false false false xbrli:monetaryItemType monetary This element represents Other Comprehensive Income (Loss), Net of Tax, for the period. Includes deferred gains (losses) on qualifying hedges, unrealized holding gains (losses) on available-for-sale securities, minimum pension liability, and cumulative translation adjustment. 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 22, 23, 24, 25 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 31 -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 true 11 Comprehensive loss 1 us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest us-gaap true credit duration No definition available. false false false false false false false false false false false totallabel false 1 false true false false -191000000 -191 false false false 2 false true false false -260000000 -260 false false false 3 false true false false -44000000 -44 false false false 4 false true false false -566000000 -566 false false false xbrli:monetaryItemType monetary The 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 economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including 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 29 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a true 12 Less: Comprehensive income attributable to the noncontrolling interests 1 us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest us-gaap true debit duration No definition available. false false false false false false false false false false false false 1 false true false false 0 0 false false false 2 false true false false 56000000 56 false false false 3 false true false false 0 0 false false false 4 false true false false 82000000 82 false false false xbrli:monetaryItemType monetary The 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 noncontrolling interests, if any. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, 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 30 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 AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph A5 -Appendix A false 13 Comprehensive loss attributable to Dynegy Inc. 1 us-gaap_ComprehensiveIncomeNetOfTax us-gaap true credit duration No definition available. false false false false false false false false false false false label false 1 true true false false -191000000 -191 false false false 2 true true false false -316000000 -316 false false false 3 true true false false -44000000 -44 false false false 4 true true false false -648000000 -648 false false false xbrli:monetaryItemType monetary The 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 false 4 12 false Millions UnKnown UnKnown false true