Regulatory Matters (Tables)

12 Months Ended

Dec. 31, 2014

Regulatory Assets and Liabilities Disclosure [Abstract]

Schedule of Regulatory Assets

The following are balances and a brief description of the regulatory assets and liabilities at December 31:

	2014			2013
	(In millions)
Assets
Recoverable pension and other postretirement costs:
Pension	$	2,284		$	1,660
Other postretirement costs	234			—
Asset retirement obligation	448			394
Recoverable Michigan income taxes	267			286
Unamortized loss on reacquired debt	67			63
Other recoverable income taxes	66			71
Accrued PSCR/GCR revenue	61			—
Deferred environmental costs	59			59
Cost to achieve Performance Excellence Process	54			75
Recoverable income taxes related to securitized regulatory assets	19			126
Removal costs asset	15			—
Transitional Reconciliation Mechanism	14			—
Other	139			129
	3,727			2,863
Less amount included in current assets	(76		)	(26		)
	$	3,651		$	2,837
Securitized regulatory assets	$	34		$	231

Schedule of Regulatory Liabilities

Liabilities
Removal costs liability	$	308		$	351
Renewable energy	227			277
Over recovery of Securitization	71			72
Refundable revenue decoupling/deferred gain	67			127
Negative pension offset	67			84
Refundable income taxes	33			45
Energy optimization	24			31
Fermi 2 refueling outage	16			26
Refundable other postretirement costs	—			72
Accrued PSCR/GCR refund	—			65
Other	7			14
	$	820		$	1,164
Less amount included current liabilities	(153		)	(302		)
	$	667		$	862