XML 51 R31.htm IDEA: XBRL DOCUMENT v2.4.0.8
Asset Retirement Obligations (Tables)
 12 Months Ended
Dec. 31, 2013
Asset Retirement Obligation Disclosure [Abstract]  
Schedule of Asset Retirement Obligations [Table Text Block]
The following table provides asset retirement obligation activity for the years ended December 31, 2013 and 2012 (dollars in millions):
 
 
2013
 
2012
Asset retirement obligation at January 1
 
$
55

 
$
121

Accretion expense
 
7

 
11

Liabilities settled
 
(6
)
 
(4
)
Revision in estimated cash flows
 
—

 
(73
)
Effect of foreign currency rate change
 
—

 
—

Asset retirement obligation at December 31
 
$
56

 
$
55