Financial and Other Derivative Instruments (Fair Value of Derivative Instruments) (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 1,041	$ 567
Derivative Liabilities	(1,216)	(533)
Current derivative assets
Derivatives, Fair Value [Line Items]
Derivative Assets	794	446
Current derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(855)	(386)
Noncurrent derivative assets
Derivatives, Fair Value [Line Items]
Derivative Assets	247	121
Noncurrent derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(361)	(147)
Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(7)	(5)
Natural gas
Derivatives, Fair Value [Line Items]
Derivative Assets	336	233
Derivative Liabilities	(528)	(223)
Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	330	180
Derivative Liabilities	(325)	(168)
Environmental & Other
Derivatives, Fair Value [Line Items]
Derivative Assets	375	154
Derivative Liabilities	(356)	(137)
Derivatives designated as hedging instruments | Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	0	0
Derivative Liabilities	(4)	(4)
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	1,041	567
Derivative Liabilities	(1,212)	(529)
Derivatives not designated as hedging instruments | DTE Electric
Derivatives, Fair Value [Line Items]
Derivative Assets	15	4
Derivatives not designated as hedging instruments | Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	0	0
Derivative Liabilities	(3)	(1)
Derivatives not designated as hedging instruments | Natural gas
Derivatives, Fair Value [Line Items]
Derivative Assets	336	233
Derivative Liabilities	(528)	(223)
Derivatives not designated as hedging instruments | Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	330	180
Derivative Liabilities	(325)	(168)
Derivatives not designated as hedging instruments | Environmental & Other
Derivatives, Fair Value [Line Items]
Derivative Assets	375	154
Derivative Liabilities	(356)	(137)
Derivatives not designated as hedging instruments | FTRs — Other current assets | DTE Electric
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 15	$ 4