Financial and Other Derivative Instruments (Fair Value of Derivative Instruments) (Details) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 397	$ 652
Derivative Liabilities	(397)	(657)
Current derivative assets
Derivatives, Fair Value [Line Items]
Derivative Assets	294	540
Current derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(289)	(558)
Noncurrent derivative assets
Derivatives, Fair Value [Line Items]
Derivative Assets	103	112
Noncurrent derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(108)	(99)
Natural gas
Derivatives, Fair Value [Line Items]
Derivative Assets	207	357
Derivative Liabilities	(196)	(378)
Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	183	285
Derivative Liabilities	(198)	(275)
Other
Derivatives, Fair Value [Line Items]
Derivative Assets	5	9
Derivative Liabilities	(1)	(1)
Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	2	1
Derivative Liabilities	(2)	(3)
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	397	652
Derivative Liabilities	(397)	(657)
Derivatives not designated as hedging instruments | DTE Electric
Derivatives, Fair Value [Line Items]
Derivative Assets	5	9
Derivatives not designated as hedging instruments | Natural gas
Derivatives, Fair Value [Line Items]
Derivative Assets	207	357
Derivative Liabilities	(196)	(378)
Derivatives not designated as hedging instruments | Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	183	285
Derivative Liabilities	(198)	(275)
Derivatives not designated as hedging instruments | Other
Derivatives, Fair Value [Line Items]
Derivative Assets	5	9
Derivative Liabilities	(1)	(1)
Derivatives not designated as hedging instruments | Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	2	1
Derivative Liabilities	(2)	(3)
Derivatives not designated as hedging instruments | FTRs — Other current assets | DTE Electric
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 5	$ 9