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Acquisition (Details) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 0 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Jan. 21, 2015
Business Acquisition [Line Items]      
Total purchase price $ 240us-gaap_PaymentsToAcquireBusinessesGross $ 0us-gaap_PaymentsToAcquireBusinessesGross  
DTE Electric      
Business Acquisition [Line Items]      
Total purchase price 240us-gaap_PaymentsToAcquireBusinessesGross
/ dei_LegalEntityAxis
= dte_DTEElectricMember		 0us-gaap_PaymentsToAcquireBusinessesGross
/ dei_LegalEntityAxis
= dte_DTEElectricMember		  
DTE Electric | Natural Gas Facility in Carson City Michigan      
Business Acquisition [Line Items]      
Gas facility capacity     732dte_BusinessAcquisitionTotalPlantCapacity
/ us-gaap_BusinessAcquisitionAxis
= dte_NaturalGasFacilityinCarsonCityMichiganMember
/ dei_LegalEntityAxis
= dte_DTEElectricMember
Number of additional households served     260,000dte_BusinessAcquisitionNumberofHouseholds
/ us-gaap_BusinessAcquisitionAxis
= dte_NaturalGasFacilityinCarsonCityMichiganMember
/ dei_LegalEntityAxis
= dte_DTEElectricMember
Equity interest acquired     100.00%us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired
/ us-gaap_BusinessAcquisitionAxis
= dte_NaturalGasFacilityinCarsonCityMichiganMember
/ dei_LegalEntityAxis
= dte_DTEElectricMember
Total purchase price     $ 240us-gaap_PaymentsToAcquireBusinessesGross
/ us-gaap_BusinessAcquisitionAxis
= dte_NaturalGasFacilityinCarsonCityMichiganMember
/ dei_LegalEntityAxis
= dte_DTEElectricMember