Significant Accounting Policies (Other Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Schedule of Other Nonoperating Income, by Component [Line Items]
Allowance for equity funds used during construction	$ 9	$ 6	$ 18	$ 14
Contract services	7	7	13	14
Investment income	4	0	9	0
Equity earnings (losses) of equity method investees	0	(4)	4	(15)
Other	11	2	13	6
Total other income	31	11	57	19
DTE Electric
Schedule of Other Nonoperating Income, by Component [Line Items]
Allowance for equity funds used during construction	8	5	17	12
Contract services	6	7	12	14
Investment income	3	0	6	0
Other	3	3	5	5
Total other income	$ 20	$ 15	$ 40	$ 31