XML 98 R51.htm IDEA: XBRL DOCUMENT v2.4.0.8
Property and Equipment (Summary of Unevaluated Properties Excluded from Amortization) (Details 1) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Summary of unevaluated properties excluded from oil and natural gas properties being amortized        
Property acquisition costs $ 215,822 $ 109,275 $ 12,543 $ 317,226
Exploration and development 41,157 22,080 7,408 10,825
Capitalized interest 25,222 12,084 6,018 821
Total 282,201 143,439 25,969 328,872
Property acquisition costs 654,866      
Exploration and development 81,470      
Capitalized interest 44,145      
Total $ 780,481 $ 809,154