XML 189 R20.htm IDEA: XBRL DOCUMENT v2.4.1.9
Asset Retirement Obligations
 12 Months Ended
Dec. 31, 2014
Asset Retirement Obligation Disclosure [Abstract]  
Asset Retirement Obligation
Asset Retirement Obligations

The following table presents the balance and activity of the asset retirement obligations for the years ended December 31, 2014, 2013 and 2012 (in thousands).
 
2014(1)
 
2013
 
2012(2)
Asset retirement obligations at January 1
$
424,117

 
$
498,410

 
$
128,116

    Liability incurred upon acquiring and drilling wells
4,968

 
5,078

 
7,479

    Liability assumed in acquisition
—

 
—

 
371,365

    Revisions in estimated cash flows
(5,848
)
 
(3,077
)
 
34,654

    Liability settled or disposed in current period
(377,927
)
 
(113,071
)
 
(72,200
)
    Accretion
9,092

 
36,777

 
28,996

Asset retirement obligations at December 31
54,402

 
424,117

 
498,410

Less: current portion
—

 
87,063

 
118,504

Asset retirement obligations, net of current
$
54,402

 
$
337,054

 
$
379,906

____________________
(1)
Liability settled or disposed in the current period includes $366.0 million associated with the Gulf Properties sold in February 2014, as discussed in Note 3.
(2)
Liability assumed in acquisition represents asset retirement obligations assumed in the acquisition of oil and natural gas properties in the Gulf of Mexico during the second quarter of 2012.