Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2013

Property, Plant and Equipment [Abstract]

Schedule of Property, Plant and Equipment

Property, plant and equipment consisted of the following:

	EME				Midwest Generation
	December 31,				December 31,
(in millions)	2013		2012		2013		2012
Land	$	34	$	36	$	31	$	32
Power plant facilities	4,453		4,612		$	613	$	1,293
Leasehold improvements	4		4		—		—
Emission allowances	541		672		496		639
Construction in progress1	54		495		53		28
Equipment, furniture and fixtures	105		128		8		13
Plant and equipment under lease financing	—		—		1,333		1,333
	5,191		5,947		2,534		3,338
Less accumulated depreciation and amortization	1,314		1,431		1,011		1,260
Net property, plant and equipment	$	3,877	$	4,516	$	1,523	$	2,078

¹  Included $466 million at December 31, 2012 for EME's new gas and wind projects under construction.

Schedule of Changes in ARO Liability

A reconciliation of the changes in Midwest Generation's ARO liability is as follows:

	Years Ended December 31,
(in millions)	2013		2012		2011
Beginning balance	$	2	$	2	$	2
Accretion expense	—		—		1
Revisions	—		—		(1		)
Ending balance	$	2	$	2	$	2

A reconciliation of the changes in EME's ARO liability is as follows:

	Years Ended December 31,
(in millions)	2013		2012		2011
Beginning balance	$	80	$	70	$	47
Accretion expense	6		5		5
Revisions	—		—		(1		)
Liabilities added	8		5		19
Ending balance	$	94	$	80	$	70