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Commitments and Contingencies (Details Textuals) (USD $)
3 Months Ended 0 Months Ended 4 Months Ended
Mar. 31, 2015
May 16, 2014
kWh
May 15, 2014
kWh
Dec. 31, 2010
dte_instances
Dec. 31, 2014
Loss Contingencies [Line Items]          
Number of NOVs       2dte_NumberOfNovs  
Possible environmental capital expenditures to comply with requirements $ 1,000,000dte_PossibleEnvironmentalCapitalExpendituresToComplyWithRequirements        
Estimated maximum spend to upgrade treatment technology to biological treatment to meet future requirements 15,000,000dte_Estimatedmaximumspendtoupgradetreatmenttechnologytobiologicaltreatmenttomeetfuturerequirements        
Length of notice of intent to sue from the Group Against Smog and Pollution 60 days        
Fine related to consent order and agreement with Allegheny County related to NOV 300,000dte_FinerelatedtoconsentorderandagreementwithAlleghenyCountyrelatedtoNOV        
Estimated expenditures for a supplemental environmental project to enhance particulate collection efficiency 300,000dte_Estimatedexpendituresforasupplementalenvironmentalprojecttoenhanceparticulatecollectionefficiency        
EPA sulfur dioxide ambient air quality standard 1 hour        
Commitment amount 8,200,000,000us-gaap_PurchaseObligation        
Future commitments 2,600,000,000us-gaap_PurchaseObligationFutureMinimumPaymentsRemainderOfFiscalYear        
Represented employees          
Loss Contingencies [Line Items]          
Entity number of employees 4,900dei_EntityNumberOfEmployees
/ us-gaap_CollectiveBargainingArrangementAxis
= dte_RepresentedEmployeesMember
       
Synthetic Fuel          
Loss Contingencies [Line Items]          
Maximum potential liability 850,000,000us-gaap_GuaranteeObligationsMaximumExposure
/ us-gaap_GuaranteeObligationsByNatureAxis
= dte_SyntheticFuelMember
       
Emissions          
Loss Contingencies [Line Items]          
Maximum potential liability 192,000,000us-gaap_GuaranteeObligationsMaximumExposure
/ us-gaap_GuaranteeObligationsByNatureAxis
= dte_ReducedEmissionsFuelGuaranteesMember
       
Other Guarantees          
Loss Contingencies [Line Items]          
Maximum potential liability 63,000,000us-gaap_GuaranteeObligationsMaximumExposure
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_GuaranteeTypeOtherMember
       
Performance Surety Bonds          
Loss Contingencies [Line Items]          
Performance bonds outstanding 49,000,000us-gaap_GuaranteeObligationsCurrentCarryingValue
/ us-gaap_GuaranteeObligationsByNatureAxis
= us-gaap_SuretyBondMember
       
DTE Electric          
Loss Contingencies [Line Items]          
Environmental capital expenditures through prior year end 2,200,000,000dte_EnvironmentalCapitalExpendituresThroughPriorYearEnd
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Environmental capital expenditures in current year 100,000,000dte_EnvironmentalCapitalExpendituresInCurrentYear
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Environmental capital expenditures in future years 30,000,000dte_EnvironmentalCapitalExpendituresInFutureYears
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
EPA is alleging detroit edison power plants violated new source performance standards 5dte_EPAisAllegingPowerPlantsViolatedNewSourcePerformanceStandards
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Number of NOVs/FOVs currently being discussed with the EPA 2dte_NumberofNOVsFOVscurrentlybeingdiscussedwiththeEPA
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Time period to complete studies on cooling water intake structures impacts on fish - EPA ruling 3 years        
Number of former MGP sites 3dte_NumberOfFormerMgpSites
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Accrual for environmental loss contingencies, gross 9,000,000us-gaap_AccrualForEnvironmentalLossContingenciesGross
/ dei_LegalEntityAxis
= dte_DTEElectricMember
      10,000,000us-gaap_AccrualForEnvironmentalLossContingenciesGross
/ dei_LegalEntityAxis
= dte_DTEElectricMember
Insurance coverage for extra expense when to necessitate power plant when unavailable 490,000,000dte_InsuranceCoverageforExtraExpensewhenPowerPlantUnavailable
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Waiting period of policy 84 days        
Period of coverage of policy for extra expenses 3 years        
Primary coverage 1,500,000,000dte_PrimaryCoverageforStabilizationDecontaminationDebrisRemovalRepairandReplacementofPropertyandDecommissioning
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Coverage for stabilization decontamination debris removal repair and replacement of property and decommissioning 1,250,000,000dte_ExcessCoverageforStabilizationDecontaminationDebrisRemovalRepairandReplacementofPropertyandDecommissioning
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Combined coverage limit for total property damage 2,750,000,000dte_CombinedCoverageLimitForTotalPropertyDamage
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Insurance deductible for nuclear power plant 1,000,000dte_InsuranceDeductibleForNuclearPowerPlant
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Total limit for property damage for non-nuclear events 2,000,000,000dte_TotalLimitForPropertyDamageForNonNuclearEvents
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Limit for property damage for non-nuclear events aggregate of extra expenses 328,000,000dte_LimitofCoverageforAggregateExtraExpensesforNonNuclearEvents
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Limit for property damage for non-nuclear events aggregate of extra expenses of period 2 years        
Time period for TRIA insurance after the first loss from terrorism 1 year        
NEIL policies against terrorism loss 3,200,000,000dte_NEILPoliciesAgainstTerrorismLoss
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Amount per event loss associated with nuclear power plants 43,000,000dte_AmountPerEventLossAssociatedWithNuclearPowerPlants
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Maintenance of public liability insurance for nuclear power plants 375,000,000dte_MaintenanceOfPublicLiabilityInsuranceForNuclearPowerPlants
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Aggregate limit of liabilities arises from terrorist act outside scope of trials subject to one industry 300,000,000dte_AggregateLimitofLiabilitiesArisesFromTerroristActOutsideScopeofTrialsSubjecttoOneIndustry
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Deferred premium charged levied against each licensed nuclear facility 127,000,000dte_MaximumDeferredPremiumChargesLeviedAgainstEachLicensedNuclearFacility
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Limit deferred premium charges per year 19,000,000dte_LimitDeferredPremiumChargesPerYear
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Company obligated to pay DOE fee of Fermi 2 electricity generated and sold     1dte_CompanyObligatedToPayDoeFeeOfFermi2ElectricityGeneratedAndSold
/ dei_LegalEntityAxis
= dte_DTEElectricMember
   
New DOE fee for nuclear waste   0dte_NewDOEfeefornuclearwaste
/ dei_LegalEntityAxis
= dte_DTEElectricMember
     
Commitment amount 2,400,000,000us-gaap_PurchaseObligation
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
Future commitments 1,900,000,000us-gaap_PurchaseObligationFutureMinimumPaymentsRemainderOfFiscalYear
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
DTE Electric | Represented employees          
Loss Contingencies [Line Items]          
Entity number of employees 2,600dei_EntityNumberOfEmployees
/ us-gaap_CollectiveBargainingArrangementAxis
= dte_RepresentedEmployeesMember
/ dei_LegalEntityAxis
= dte_DTEElectricMember
       
DTE Gas          
Loss Contingencies [Line Items]          
Number of former MGP sites 14dte_NumberOfFormerMgpSites
/ dei_LegalEntityAxis
= dte_DTEGasMember
       
Accrual for environmental loss contingencies, gross $ 23,000,000us-gaap_AccrualForEnvironmentalLossContingenciesGross
/ dei_LegalEntityAxis
= dte_DTEGasMember
      $ 24,000,000us-gaap_AccrualForEnvironmentalLossContingenciesGross
/ dei_LegalEntityAxis
= dte_DTEGasMember
Period gas utility can amortize MGP costs 10 years        
DTE Gas | Cleanup completed and site closed          
Loss Contingencies [Line Items]          
Number of former MGP sites 4dte_NumberOfFormerMgpSites
/ us-gaap_EnvironmentalRemediationSiteAxis
= dte_CleanupcompletedandsiteclosedMember
/ dei_LegalEntityAxis
= dte_DTEGasMember
       
DTE Gas | Complete closure expected by end of fiscal year          
Loss Contingencies [Line Items]          
Number of former MGP sites 2dte_NumberOfFormerMgpSites
/ us-gaap_EnvironmentalRemediationSiteAxis
= dte_PartialclosurecompletedMember
/ dei_LegalEntityAxis
= dte_DTEGasMember