Financial and Other Derivative Instruments (Fair Value of Derivative Instruments) (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 439	$ 549
Derivative Liabilities	(409)	(656)
Current derivative assets
Derivatives, Fair Value [Line Items]
Derivative Assets	301	447
Current derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(297)	(493)
Noncurrent derivative assets
Derivatives, Fair Value [Line Items]
Derivative Assets	138	102
Noncurrent derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(112)	(163)
Natural Gas
Derivatives, Fair Value [Line Items]
Derivative Assets	230	348
Derivative Liabilities	(204)	(461)
Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	202	193
Derivative Liabilities	(199)	(189)
Other
Derivatives, Fair Value [Line Items]
Derivative Assets	4	2
Derivative Liabilities	(2)	(3)
Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	3	6
Derivative Liabilities	(4)	(3)
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	439	549
Derivative Liabilities	(409)	(656)
Derivatives not designated as hedging instruments | DTE Electric
Derivatives, Fair Value [Line Items]
Derivative Assets	4	2
Derivatives not designated as hedging instruments | Natural Gas
Derivatives, Fair Value [Line Items]
Derivative Assets	230	348
Derivative Liabilities	(204)	(461)
Derivatives not designated as hedging instruments | Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	202	193
Derivative Liabilities	(199)	(189)
Derivatives not designated as hedging instruments | Other
Derivatives, Fair Value [Line Items]
Derivative Assets	4	2
Derivative Liabilities	(2)	(3)
Derivatives not designated as hedging instruments | Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	3	6
Derivative Liabilities	(4)	(3)
Derivatives not designated as hedging instruments | FTRs — Other current assets | DTE Electric
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 4	$ 2