Financial and Other Derivative Instruments (Fair Value of Derivative Instruments) (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 711	$ 1,178
Derivative Liabilities	(705)	(1,110)
Natural Gas
Derivatives, Fair Value [Line Items]
Derivative Assets	387	787
Derivative Liabilities	(383)	(718)
Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	307	342
Derivative Liabilities	(305)	(342)
Other
Derivatives, Fair Value [Line Items]
Derivative Assets	5	45
Derivative Liabilities	(10)	(45)
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Assets	711	1,178
Derivative Liabilities	(705)	(1,110)
Not Designated as Hedging Instrument | Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	12	4
Derivative Liabilities	(7)	(5)
Not Designated as Hedging Instrument | Natural Gas
Derivatives, Fair Value [Line Items]
Derivative Assets	387	787
Derivative Liabilities	(383)	(718)
Not Designated as Hedging Instrument | Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	307	342
Derivative Liabilities	(305)	(342)
Not Designated as Hedging Instrument | Other
Derivatives, Fair Value [Line Items]
Derivative Assets	5	45
Derivative Liabilities	(10)	(45)
Current Derivative Asset
Derivatives, Fair Value [Line Items]
Derivative Assets	570	1,083
Noncurrent Derivative Asset
Derivatives, Fair Value [Line Items]
Derivative Assets	141	95
Current Derivative Liability
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(521)	(1,041)
Noncurrent Derivative Liability
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(184)	(69)
DTE Electric | Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Assets	3	3
DTE Electric | Not Designated as Hedging Instrument | Other
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 3	$ 3