Retirement Benefits and Trusteed Assets (Tables)

9 Months Ended

Sep. 30, 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 September 30,	(In millions)
Service cost	$	27		$	19		$	8		$	8
Interest cost	52			54			20			22
Expected return on plan assets	(74		)	(69		)	(33		)	(31		)
Amortization of:
Net actuarial loss	51			42			10			4
Prior service credit	—			—			(31		)	(36		)
Net periodic benefit cost (credit)	$	56		$	46		$	(26	)	$	(33	)

	Pension Benefits						Other Postretirement Benefits
	2015			2014			2015			2014
Nine Months Ended September 30,	(In millions)
Service cost	$	76		$	62		$	25		$	26
Interest cost	158			159			61			67
Expected return on plan assets	(222		)	(205		)	(98		)	(92		)
Amortization of:
Net actuarial loss	154			118			32			15
Prior service credit	—			—			(94		)	(108		)
Net periodic benefit cost (credit)	$	166		$	134		$	(74	)	$	(92	)

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 September 30,	(In millions)
Service cost	$	21		$	14		$	6		$	6
Interest cost	39			41			15			17
Expected return on plan assets	(53		)	(48		)	(23		)	(21		)
Amortization of:
Net actuarial loss	36			30			8			3
Prior service credit	—			—			(24		)	(27		)
Net periodic benefit cost (credit)	$	43		$	37		$	(18	)	$	(22	)

	Pension Benefits						Other Postretirement Benefits
	2015			2014			2015			2014
Nine Months Ended September 30,	(In millions)
Service cost	$	59		$	48		$	19		$	19
Interest cost	120			121			46			51
Expected return on plan assets	(158		)	(145		)	(68		)	(63		)
Amortization of:
Net actuarial loss	110			83			24			11
Prior service cost (credit)	1			1			(71		)	(82		)
Net periodic benefit cost (credit)	$	132		$	108		$	(50	)	$	(64	)

Schedule of Contributions

During 2015, DTE Energy contributed the following amounts of DTE Energy common stock to the DTE Energy Company Master VEBA Trust for funding its other postretirement benefit plans:

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