Retirement Benefits and Trusteed Assets (OPEB - Reconciliation of Obligations, Assets and Funded Status of Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Amounts recognized in Regulatory assets
Regulatory assets	$ 6,317	$ 4,336
Other postretirement benefit plan
Change in accumulated postretirement benefit obligation
Projected/Accumulated postretirement benefit obligation, beginning of year	1,293	1,702
Service cost	17	27	$ 30
Interest cost	65	48	46
Actuarial (gain) loss	(5)	(395)
Benefits paid	(87)	(89)
Projected/Accumulated postretirement benefit obligation, end of year	1,283	1,293	1,702
Change in plan assets
Plan assets at fair value, beginning of year	1,577	2,021
Actual return on plan assets	124	(359)
Benefits paid	(87)	(85)
Plan assets at fair value, end of year	1,614	1,577	2,021
Funded status	331	284
Amount recorded as:
Noncurrent assets	633	571
Current liabilities	(1)	0
Noncurrent liabilities	(301)	(287)
Defined benefit plans assets (liabilities)	331	284
Amounts recognized in Accumulated other comprehensive income (loss), pre-tax
Net actuarial gain	(13)	(14)
Amounts recognized in Regulatory assets
Net actuarial loss	173	201
Prior service credit	(10)	(29)
Regulatory assets	163	172
DTE Electric
Amounts recognized in Regulatory assets
Regulatory assets	5,695	3,640
DTE Electric | Other postretirement benefit plan
Change in accumulated postretirement benefit obligation
Projected/Accumulated postretirement benefit obligation, beginning of year	982	1,293
Service cost	13	20	23
Interest cost	49	37	35
Actuarial (gain) loss	2	(301)
Benefits paid	(64)	(67)
Projected/Accumulated postretirement benefit obligation, end of year	982	982	1,293
Change in plan assets
Plan assets at fair value, beginning of year	1,052	1,355
Actual return on plan assets	81	(239)
Benefits paid	(63)	(64)
Plan assets at fair value, end of year	1,070	1,052	$ 1,355
Funded status	88	70
Amount recorded as:
Noncurrent assets	378	345
Current liabilities	0	0
Noncurrent liabilities	(290)	(275)
Defined benefit plans assets (liabilities)	88	70
Amounts recognized in Accumulated other comprehensive income (loss), pre-tax
Net actuarial gain	0	0
Amounts recognized in Regulatory assets
Net actuarial loss	73	80
Prior service credit	(6)	(20)
Regulatory assets	$ 67	$ 60