Revenue (Disaggregation of Revenue) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 3,288	$ 3,284	$ 2,583	$ 3,022	$ 3,148	$ 3,119	$ 2,888	$ 3,514	$ 12,177	$ 12,669	$ 14,212
Lease revenue outside scope of Topic 606									190	193
Electric
Disaggregation of Revenue [Line Items]
Revenues									5,520	5,229	5,298
Alternative Revenue Program revenues outside scope of Topic 606									26	22	21
Other revenues outside scope of topic 606									22	19	20
Electric | Residential
Disaggregation of Revenue [Line Items]
Revenues									2,825	2,427	2,494
Electric | Commercial
Disaggregation of Revenue [Line Items]
Revenues									1,739	1,795	1,794
Electric | Industrial
Disaggregation of Revenue [Line Items]
Revenues									592	659	690
Electric | Other
Disaggregation of Revenue [Line Items]
Revenues									364	348	320
Electric | Other | DTE Sustainable Generation
Disaggregation of Revenue [Line Items]
Revenues									14	5
Gas
Disaggregation of Revenue [Line Items]
Revenues									1,414	1,482	1,436
Alternative Revenue Program revenues outside scope of Topic 606									10	8	2
Other revenues outside scope of topic 606									8	7	7
Gas | Other
Disaggregation of Revenue [Line Items]
Revenues									146	142	91
Gas | Gas sales
Disaggregation of Revenue [Line Items]
Revenues									971	1,043	1,055
Gas | End User Transportation
Disaggregation of Revenue [Line Items]
Revenues									218	219	232
Gas | Intermediate Transportation
Disaggregation of Revenue [Line Items]
Revenues									79	78	58
Gas Storage and Pipelines
Disaggregation of Revenue [Line Items]
Revenues									754	501	485
Lease revenue outside scope of Topic 606									9	9
Power and Industrial Projects
Disaggregation of Revenue [Line Items]
Revenues									1,224	1,560	2,204
Lease revenue outside scope of Topic 606									99	121
Lease revenue outside scope of Topic 606											125
Energy Trading
Disaggregation of Revenue [Line Items]
Revenues									3,863	4,610	5,557
Gain (loss) on derivative outside scope of Topic 606									$ 2,700	$ 3,400	$ 4,500