XML 15 R23.htm IDEA: XBRL DOCUMENT  v2.3.0.11
Asset Retirement Obligations (Tables)
 6 Months Ended
Jun. 30, 2011
Asset Retirement Obligations  
Asset Retirement Obligations
     Six Months Ended
June 30,		  
     2011     2010  
     (In thousands)  

ARO liability, January 1:

    $ 69,265      $ 56,404   

Accretion of discount

      1,735        1,393   

Liability incurred

      2,879        1,402   

Liability settled

      (666 )      (442 ) 

Revision of estimates

      9        91   
                

ARO liability, June 30:

      73,222        58,848   

Less current portion

      1,781        1,760   
                

Total long-term ARO liability

    $ 71,441      $ 57,088