Commitments and Contingencies (Details Textuals)			1 Months Ended	4 Months Ended	9 Months Ended	12 Months Ended
	Jan. 13, 2015 USD ($)	May. 16, 2014 kWh	May. 31, 2014	May. 15, 2014 $ / MWh	Sep. 30, 2015 USD ($) employee facility instance facilities	Dec. 31, 2014 USD ($)	Dec. 31, 2010 instance	Jul. 31, 2009 facility
Loss Contingencies [Line Items]
Number of NOVs | instance							2
Possible environmental capital expenditures to comply with requirements					$ 1,000,000
Estimated maximum spend to upgrade treatment technology to biological treatment to meet future requirements					15,000,000
Fine related to consent order and agreement with Allegheny County related to NOV					300,000
Estimated expenditures for a supplemental environmental project to enhance particulate collection efficiency					300,000
EPA sulfur dioxide ambient air quality standard							1 hour
Commitment amount					7,400,000,000
Future commitments					$ 2,500,000,000.0
Represented employees
Loss Contingencies [Line Items]
Entity number of employees | employee					4,900
Synthetic Fuel
Loss Contingencies [Line Items]
Term after expiration of statutes of limitations					90 days
Maximum potential liability					$ 850,000,000
Emissions
Loss Contingencies [Line Items]
Term after expiration of statutes of limitations					90 days
Maximum potential liability					$ 238,000,000
Other Guarantees
Loss Contingencies [Line Items]
Maximum potential liability					66,000,000
Performance Surety Bonds
Loss Contingencies [Line Items]
Performance bonds outstanding					$ 49,000,000
DTE Electric
Loss Contingencies [Line Items]
EPA is alleging detroit edison power plants violated new source performance standards | facility								5
Number of NOVs/FOVs currently being discussed with the EPA | instance					2
Environmental capital expenditures through prior year end						$ 2,200,000,000
Environmental capital expenditures in current year					$ 100,000,000
Environmental capital expenditures in future years					$ 50,000,000
Time period to complete studies on cooling water intake structures impacts on fish - EPA ruling			3 years
Number of former MGP sites | facility					3
Accrual for environmental loss contingencies, gross					$ 9,000,000	10,000,000
Waiting period of policy					84 days
Insurance coverage for extra expense when to necessitate power plant when unavailable					$ 490,000,000
Period of coverage of policy for extra expenses					3 years
Primary coverage					$ 1,500,000,000
Coverage for stabilization decontamination debris removal repair and replacement of property and decommissioning					1,250,000,000
Combined coverage limit for total property damage					2,750,000,000
Total limit for property damage for non-nuclear events					2,000,000,000
Limit for property damage for non-nuclear events aggregate of extra expenses					$ 328,000,000
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	$ 3,200,000,000.0
Amount per event loss associated with nuclear power plants					$ 46,000,000
Maintenance of public liability insurance for nuclear power plants					375,000,000
Aggregate limit of liabilities arises from terrorist act outside scope of trials subject to one industry					300,000,000
Deferred premium charged levied against each licensed nuclear facility					127,000,000
Maximum deferred premium charges per year					19,000,000
Company obligated to pay DOE fee of Fermi 2 electricity generated and sold | $ / MWh				1
New DOE fee for nuclear waste | kWh		0
Commitment amount					2,200,000,000
Future commitments					$ 1,800,000,000.0
DTE Electric | Represented employees
Loss Contingencies [Line Items]
Entity number of employees | employee					2,600
DTE Electric | Coal Combustion Residual Rule
Loss Contingencies [Line Items]
Period in which new facilities are expected to be built, years					7 years
Estimated cost of compliance					$ 190,000,000
DTE Gas
Loss Contingencies [Line Items]
Number of former MGP sites | facility					14
Accrual for environmental loss contingencies, gross					$ 23,000,000	$ 24,000,000
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 | facility					5
DTE Gas | Complete closure expected by end of fiscal year
Loss Contingencies [Line Items]
Number of former MGP sites | facilities					2