Retirement Benefits and Trusteed Assets (Tables)

3 Months Ended

Mar. 31, 2015

Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]

Schedule of Net Benefit Costs

The following table details the components of net periodic benefit costs for pension benefits and other postretirement benefits for DTE Energy:

	Pension Benefits						Other Postretirement Benefits
	2015			2014			2015			2014
Three Months Ended March 31,	(In millions)
Service cost	$	25		$	21		$	9		$	9
Interest cost	53			53			20			23
Expected return on plan assets	(74		)	(68		)	(33		)	(31		)
Amortization of:
Net actuarial loss	51			38			11			5
Prior service credit	—			—			(31		)	(36		)
Net periodic benefit cost (credit)	$	55		$	44		$	(24	)	$	(30	)

The following table details the components of net periodic benefit costs for pension benefits and other postretirement benefits for DTE Electric:

	Pension Benefits						Other Postretirement Benefits
	2015			2014			2015			2014
Three Months Ended March 31,	(In millions)
Service cost	$	20		$	17		$	7		$	7
Interest cost	40			40			16			17
Expected return on plan assets	(53		)	(48		)	(23		)	(21		)
Amortization of:
Net actuarial loss	38			27			8			3
Prior service cost (credit)	—			—			(24		)	(27		)
Net periodic benefit cost (credit)	$	45		$	36		$	(16	)	$	(21	)

Schedule of Contributions

During 2015, DTE Energy contributed the following amounts of DTE Energy common stock to the DTE Energy Company Master VEBA Trust:

Date	Number of Shares	Price per Share	Amount
			(In millions)
February 17, 2015	1,427,835	$81.91	$	117
			$	117