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Fair Value (Gains and Losses and Proceeds from the Sale of Securities by the Nuclear Trust Funds) (Details) (DTE Electric, Nuclear decommissioning trust fund, USD $)
In Millions, unless otherwise specified
 3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
DTE Electric | Nuclear decommissioning trust fund
    
Schedule of Available-for-sale Securities [Line Items]    
Realized gains $ 9us-gaap_AvailableForSaleSecuritiesGrossRealizedGains
/ us-gaap_FairValueByAssetClassAxis
= dte_NuclearDecommissioningTrustFundMember
/ dei_LegalEntityAxis
= dte_DTEElectricMember		 $ 9us-gaap_AvailableForSaleSecuritiesGrossRealizedGains
/ us-gaap_FairValueByAssetClassAxis
= dte_NuclearDecommissioningTrustFundMember
/ dei_LegalEntityAxis
= dte_DTEElectricMember
Realized losses (7)us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses
/ us-gaap_FairValueByAssetClassAxis
= dte_NuclearDecommissioningTrustFundMember
/ dei_LegalEntityAxis
= dte_DTEElectricMember		 (7)us-gaap_AvailableForSaleSecuritiesGrossRealizedLosses
/ us-gaap_FairValueByAssetClassAxis
= dte_NuclearDecommissioningTrustFundMember
/ dei_LegalEntityAxis
= dte_DTEElectricMember
Proceeds from sales of securities $ 246us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= dte_NuclearDecommissioningTrustFundMember
/ dei_LegalEntityAxis
= dte_DTEElectricMember		 $ 271us-gaap_ProceedsFromSaleOfAvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= dte_NuclearDecommissioningTrustFundMember
/ dei_LegalEntityAxis
= dte_DTEElectricMember