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Asset Retirement Obligations
9 Months Ended
Sep. 30, 2012
Asset Retirement Obligation [Abstract]  
Asset Retirement Obligation Disclosure [Text Block]
ASSET RETIREMENT OBLIGATIONS

A reconciliation of the asset retirement obligations for the nine months ended September 30, 2012 follows (in millions):
Asset retirement obligations at December 31, 2011
$
1,593

Accretion
73

Revision in estimated cash flows
11

Liabilities incurred
14

Liabilities settled
(8
)
Asset retirement obligations at September 30, 2012
$
1,683