Financial and Other Derivative Instruments (Fair Value of Derivative Instruments) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 781	$ 775
Derivative Liabilities	(746)	(770)
Current derivative assets
Derivatives, Fair Value [Line Items]
Derivative Assets	601	646
Current derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(577)	(596)
Noncurrent derivative assets
Derivatives, Fair Value [Line Items]
Derivative Assets	180	129
Noncurrent derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(169)	(174)
Natural gas
Derivatives, Fair Value [Line Items]
Derivative Assets	282	355
Derivative Liabilities	(278)	(351)
Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	313	306
Derivative Liabilities	(317)	(298)
Environmental & Other
Derivatives, Fair Value [Line Items]
Derivative Assets	179	113
Derivative Liabilities	(149)	(121)
Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	7	1
Derivative Liabilities	(2)	0
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	781	775
Derivative Liabilities	(746)	(770)
Derivatives not designated as hedging instruments | DTE Electric
Derivatives, Fair Value [Line Items]
Derivative Assets	1	3
Derivatives not designated as hedging instruments | Natural gas
Derivatives, Fair Value [Line Items]
Derivative Assets	282	355
Derivative Liabilities	(278)	(351)
Derivatives not designated as hedging instruments | Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	313	306
Derivative Liabilities	(317)	(298)
Derivatives not designated as hedging instruments | Environmental & Other
Derivatives, Fair Value [Line Items]
Derivative Assets	179	113
Derivative Liabilities	(149)	(121)
Derivatives not designated as hedging instruments | Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	7	1
Derivative Liabilities	(2)	0
Derivatives not designated as hedging instruments | FTRs — Other current assets | DTE Electric
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 1	$ 3