Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation (Share-Based Compensation Expense) (Details)

v2.4.0.8
Share-Based Compensation (Share-Based Compensation Expense) (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense - Equity-based $ 4,194 [1] $ 4,428 [1] $ 3,058 [1]
Share-based compensation expense - Liability-based 5,347 2,916 1,335
Options [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense - Equity-based 0 0 24
RSUs [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense - Equity-based 3,975 4,210 2,832
Cash-settleable RSU awards [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense - Equity-based 0 0 0
Share-based compensation expense - Liability-based 5,347 2,916 1,335
Contribution 401K in Shares Plan [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense - Equity-based 219 218 202
General and Administrative Expense [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation expense - Equity-based 5,751 4,081 2,502
Portion Capitalized to Oil and Gas Properties [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation - capitalized $ 3,791 $ 3,263 $ 1,891
[1] The portion of this share-based compensation expense that was included in general and administrative expense totaled $5,751, $4,081 and $2,502 for the same years respectively, and the portion capitalized to oil and gas properties was $3,791, $3,263 and $1,891, respectively.