Financial and Other Derivative Instruments (Fair Value of Derivative Instruments) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 685	$ 711
Derivative Liabilities	(763)	(705)
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Assets	685	711
Derivative Liabilities	(763)	(705)
DTE Electric | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Assets	1	3
Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	6	12
Derivative Liabilities	(4)	(7)
Foreign currency exchange contracts | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Assets	6	12
Derivative Liabilities	(4)	(7)
Natural Gas
Derivatives, Fair Value [Line Items]
Derivative Assets	298	387
Derivative Liabilities	(350)	(383)
Natural Gas | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Assets	298	387
Derivative Liabilities	(350)	(383)
Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	377	307
Derivative Liabilities	(396)	(305)
Electricity | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Assets	377	307
Derivative Liabilities	(396)	(305)
Other
Derivatives, Fair Value [Line Items]
Derivative Assets	4	5
Derivative Liabilities	(13)	(10)
Other | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Assets	4	5
Derivative Liabilities	(13)	(10)
Financial transmission rights | DTE Electric | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Assets	1	3
Current derivative asset
Derivatives, Fair Value [Line Items]
Derivative Assets	527	570
Current derivative liability
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(545)	(521)
Noncurrent derivative asset
Derivatives, Fair Value [Line Items]
Derivative Assets	158	141
Noncurrent derivative liability
Derivatives, Fair Value [Line Items]
Derivative Liabilities	$ (218)	$ (184)