Retirement Benefits and Trusteed Assets (Tables)

9 Months Ended

Sep. 30, 2019

Defined Benefit Plan [Abstract]

Schedule of Net Periodic Benefit Costs (Credits)

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

	Other Postretirement Benefits
	Three Months Ended September 30,
	2019			2018
	(In millions)
Service cost	$	4		$	5
Interest cost	13			13
Expected return on plan assets	(21		)	(25		)
Amortization of:
Net actuarial loss	1			3
Prior service credit	(1		)	—
Net periodic benefit credit	$	(4	)	$	(4	)

	Other Postretirement Benefits
	Nine Months Ended September 30,
	2019			2018
	(In millions)
Service cost	$	12		$	15
Interest cost	40			40
Expected return on plan assets	(63		)	(74		)
Amortization of:
Net actuarial loss	3			7
Prior service credit	(5		)	—
Net periodic benefit credit	$	(13	)	$	(12	)

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 September 30,
	2019			2018			2019			2018
	(In millions)
Service cost	$	21		$	24		$	5		$	6
Interest cost	55			51			18			18
Expected return on plan assets	(82		)	(82		)	(30		)	(36		)
Amortization of:
Net actuarial loss	33			43			3			3
Prior service credit	—			—			(3		)	—
Net periodic benefit cost (credit)	$	27		$	36		$	(7	)	$	(9	)

	Pension Benefits						Other Postretirement Benefits
	Nine Months Ended September 30,
	2019			2018			2019			2018
	(In millions)
Service cost	$	63		$	74		$	16		$	20
Interest cost	164			151			53			52
Expected return on plan assets	(244		)	(247		)	(92		)	(107		)
Amortization of:
Net actuarial loss	99			132			9			8
Prior service credit	—			—			(7		)	—
Net periodic benefit cost (credit)	$	82		$	110		$	(21	)	$	(27	)

Schedule of Defined Benefit Plans Disclosures

During 2019, DTE Energy contributed the following amounts of DTE Energy common stock to the DTE Energy Company Affiliates Employee Benefit Plans Master Trust:

Date	Number of Shares	Price per Share		Amount
				(In millions)
March 5, 2019	814,597	$	122.76	$	100