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Jointly Owned Utility Plant (Detail Textuals)
Dec. 31, 2014
facilities
Jointly Owned Utility Plant Interests [Line Items]  
Jointly Owned Utility Plant Number of Plants 2dte_JointlyOwnedUtilityPlantNumberOfPlants
Belle River Unit 1 [Member]  
Jointly Owned Utility Plant Interests [Line Items]  
Jointly Owned Utility Plant, Proportionate Ownership Share 63.00%us-gaap_JointlyOwnedUtilityPlantProportionateOwnershipShare
/ us-gaap_JointlyOwnedUtilityPlantAxis
= dte_BelleRiverUnit1Member
Belle River Facilities used jointly by Belle River and St. Clair Power Plants [Member]  
Jointly Owned Utility Plant Interests [Line Items]  
Jointly Owned Utility Plant, Proportionate Ownership Share 81.00%us-gaap_JointlyOwnedUtilityPlantProportionateOwnershipShare
/ us-gaap_JointlyOwnedUtilityPlantAxis
= dte_BelleRiverFacilitiesusedjointlybyBelleRiverandSt.ClairPowerPlantsMember
Belle River [Member]  
Jointly Owned Utility Plant Interests [Line Items]  
Joint Owners Percentage of the Total Capacity Energy and Related Responsibilities 19.00%dte_JointOwnersPercentageOfTotalCapacityEnergyAndRelatedResponsibilities
/ us-gaap_JointlyOwnedUtilityPlantAxis
= dte_BelleRiverMember
Belle River Unit 2 [Member]  
Jointly Owned Utility Plant Interests [Line Items]  
Jointly Owned Utility Plant, Proportionate Ownership Share 75.00%us-gaap_JointlyOwnedUtilityPlantProportionateOwnershipShare
/ us-gaap_JointlyOwnedUtilityPlantAxis
= dte_BelleRiverUnit2Member
Ludington Hydroelectric Pumped Storage [Member]  
Jointly Owned Utility Plant Interests [Line Items]  
Jointly Owned Utility Plant, Proportionate Ownership Share 49.00%us-gaap_JointlyOwnedUtilityPlantProportionateOwnershipShare
/ us-gaap_JointlyOwnedUtilityPlantAxis
= dte_LudingtonHydroelectricPumpedStorageMember
Joint Owners Percentage of the Total Capacity Energy and Related Responsibilities 51.00%dte_JointOwnersPercentageOfTotalCapacityEnergyAndRelatedResponsibilities
/ us-gaap_JointlyOwnedUtilityPlantAxis
= dte_LudingtonHydroelectricPumpedStorageMember