Financial and Other Derivative Instruments (Fair Value of Derivative Instruments) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 968	$ 1,922
Derivative Liabilities	(970)	(2,169)
Current derivative assets
Derivatives, Fair Value [Line Items]
Derivative Assets	733	1,517
Current derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(657)	(1,535)
Noncurrent derivative assets
Derivatives, Fair Value [Line Items]
Derivative Assets	235	405
Noncurrent derivative liabilities
Derivatives, Fair Value [Line Items]
Derivative Liabilities	(313)	(634)
Interest rate contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	22	1
Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	1	1
Derivative Liabilities	(1)	(2)
Natural gas
Derivatives, Fair Value [Line Items]
Derivative Assets	441	744
Derivative Liabilities	(476)	(1,018)
Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	333	963
Derivative Liabilities	(318)	(935)
Environmental & Other
Derivatives, Fair Value [Line Items]
Derivative Assets	171	213
Derivative Liabilities	(175)	(214)
Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	22	1
Derivative Liabilities	(1)	(2)
Derivatives designated as hedging instruments | Interest rate contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	22	1
Derivative Liabilities	0	0
Derivatives designated as hedging instruments | Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	0	0
Derivative Liabilities	(1)	(2)
Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Derivative Assets	946	1,921
Derivative Liabilities	(969)	(2,167)
Derivatives not designated as hedging instruments | Foreign currency exchange contracts
Derivatives, Fair Value [Line Items]
Derivative Assets	1	1
Derivative Liabilities	0	0
Derivatives not designated as hedging instruments | Natural gas
Derivatives, Fair Value [Line Items]
Derivative Assets	441	744
Derivative Liabilities	(476)	(1,018)
Derivatives not designated as hedging instruments | Electricity
Derivatives, Fair Value [Line Items]
Derivative Assets	333	963
Derivative Liabilities	(318)	(935)
Derivatives not designated as hedging instruments | Environmental & Other
Derivatives, Fair Value [Line Items]
Derivative Assets	171	213
Derivative Liabilities	(175)	(214)
Derivatives not designated as hedging instruments | FTRs | Other current assets | DTE Electric
Derivatives, Fair Value [Line Items]
Derivative Assets	$ 10	$ 11