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Fair Value (Fair Value of Nuclear Decommissioning Trust Fund Assets) (Details) (USD $)
In Millions, unless otherwise specified
Dec. 31, 2014
Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]    
Decommissioning Fund Investments $ 1,241us-gaap_DecommissioningFundInvestments $ 1,191us-gaap_DecommissioningFundInvestments
Fermi 2 [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Decommissioning Fund Investments 1,221us-gaap_DecommissioningFundInvestments
/ us-gaap_PublicUtilityAxis
= us-gaap_NuclearPlantMember		 1,172us-gaap_DecommissioningFundInvestments
/ us-gaap_PublicUtilityAxis
= us-gaap_NuclearPlantMember
Fermi 1 [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Decommissioning Fund Investments 3us-gaap_DecommissioningFundInvestments
/ us-gaap_PublicUtilityAxis
= dte_NuclearPlant1Member		 3us-gaap_DecommissioningFundInvestments
/ us-gaap_PublicUtilityAxis
= dte_NuclearPlant1Member
Low Level Radioactive Waste [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Decommissioning Fund Investments 17us-gaap_DecommissioningFundInvestments
/ us-gaap_PublicUtilityAxis
= dte_LowLevelRadioactiveWasteMember		 16us-gaap_DecommissioningFundInvestments
/ us-gaap_PublicUtilityAxis
= dte_LowLevelRadioactiveWasteMember
Nuclear Decommissioning Trust Fund [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Decommissioning Fund Investments $ 1,241us-gaap_DecommissioningFundInvestments
/ us-gaap_FairValueByAssetClassAxis
= dte_NuclearDecommissioningTrustFundMember		 $ 1,191us-gaap_DecommissioningFundInvestments
/ us-gaap_FairValueByAssetClassAxis
= dte_NuclearDecommissioningTrustFundMember