Asset Retirement Obligations (Tables)

6 Months Ended

Jun. 30, 2013

Asset Retirement Obligation Disclosure [Abstract]

Schedule of Change in Asset Retirement Obligation [Table Text Block]

A reconciliation of the asset retirement obligations for the six months ended June 30, 2013 follows:

	(In millions)
Asset retirement obligations at December 31, 2012	$	1,719
Accretion	52
Revision in estimated cash flows	13
Asset retirement obligations at June 30, 2013	$	1,784