Retirement Benefits and Trusteed Assets (Tables)

6 Months Ended

Jun. 30, 2021

Retirement Benefits [Abstract]

Schedule of Net Periodic Benefit Costs (Credits)

The following tables detail the components of net periodic benefit costs (credits) for pension benefits and other postretirement benefits for DTE Energy:

	Pension Benefits				Other Postretirement Benefits
	Three Months Ended June 30,
	2021		2020		2021		2020
	(In millions)
Service cost	$	27	$	24	$	7	$	7
Interest cost	40		47		12		14
Expected return on plan assets	(86)		(83)		(32)		(32)
Amortization of:
Net actuarial loss	49		43		4		3
Prior service credit	—		—		(5)		(5)
Net periodic benefit cost (credit)	$	30	$	31	$	(14)	$	(13)

	Pension Benefits				Other Postretirement Benefits
	Six Months Ended June 30,
	2021		2020		2021		2020
	(In millions)
Service cost	$	54	$	49	$	15	$	13
Interest cost	79		93		23		28
Expected return on plan assets	(170)		(166)		(64)		(64)
Amortization of:
Net actuarial loss	98		86		7		8
Prior service credit	—		—		(10)		(10)
Net periodic benefit cost (credit)	$	61	$	62	$	(29)	$	(25)

The following tables detail the components of net periodic benefit costs (credits) for other postretirement benefits for DTE Electric:

	Three Months Ended June 30,				Six Months Ended June 30,
	2021		2020		2021		2020
	(In millions)
Service cost	$	5	$	5	$	11	$	10
Interest cost	9		10		17		21
Expected return on plan assets	(21)		(22)		(43)		(44)
Amortization of:
Net actuarial loss	3		3		6		6
Prior service credit	(4)		(3)		(7)		(7)
Net periodic benefit credit	$	(8)	$	(7)	$	(16)	$	(14)