XML 49 R61.htm IDEA: XBRL DOCUMENT v2.4.0.6
Long-Term Debt (Narrative) (Details) (USD $)
 12 Months Ended 0 Months Ended 0 Months Ended 12 Months Ended 3 Months Ended 9 Months Ended 12 Months Ended 12 Months Ended
Dec. 31, 2011
Feb. 02, 2011
2019 Notes [Member]
Feb. 02, 2011
2019 Notes [Member]
Dec. 31, 2011
2019 Notes [Member]
Nov. 10, 2011
2021 Notes [Member]
Dec. 31, 2011
2021 Notes [Member]
Dec. 31, 2011
Amended Credit Facility [Member]
Oct. 05, 2011
Amended Credit Facility [Member]
Jan. 21, 2011
Amended Credit Facility [Member]
Dec. 31, 2011
Prior To January 13, 2013 [Member]
2021 Notes [Member]
Dec. 31, 2011
Prior To February 1, 2014 [Member]
2019 Notes [Member]
Dec. 31, 2011
Prior To February 1, 2015 [Member]
2019 Notes [Member]
Dec. 31, 2011
Twelve-Month Period Beginning On February 1, 2015 [Member]
2019 Notes [Member]
Dec. 31, 2011
Prior To November 1, 2014 [Member]
2021 Notes [Member]
Dec. 31, 2011
Prior To November 1, 2016 [Member]
2021 Notes [Member]
Dec. 31, 2011
Twelve-Month Period Beginning February 1, 2016 [Member]
2019 Notes [Member]
Dec. 31, 2011
Beginning On February 1, 2017 [Member]
2019 Notes [Member]
Dec. 31, 2011
Twelve-Month Period Beginning On November 1, 2016 [Member]
2021 Notes [Member]
Dec. 31, 2011
Twelve-Month Period Beginning On November 1, 2017 [Member]
2021 Notes [Member]
Dec. 31, 2011
Twelve-Month Period Beginning On November 1, 2018 [Member]
2021 Notes [Member]
Dec. 31, 2011
Beginning On November 1, 2019 [Member]
2021 Notes [Member]
Dec. 31, 2011
Line Of Credit [Member]
Jun. 16, 2011
Line Of Credit [Member]
Dec. 31, 2011
EBITDAX [Member]
Maximum [Member]
Amended Credit Facility [Member]
Dec. 31, 2011
Current Ratio [Member]
Minimum [Member]
Amended Credit Facility [Member]
Debt Instrument [Line Items]                                                  
Percentage of the reserve value of assets as determined by reserve reports 80.00%                                                
Commitment fee of borrowing base capacity not utilized 0.375%                                                
Maximum debt to EBITDAX ratio                                               4.0  
Minimum current ratio                                                 1.0
Letters of credit maximum borrowings             $ 350,000,000   $ 137,500,000                         $ 1,000,000,000 $ 600,000,000    
Letter of credit unused borrowing base capacity             350,000,000                                    
Senior unsecured debt principal amount   400,000,000 400,000,000   400,000,000                                        
Senior unsecured notes stated interest rate   7.25% 7.25%   6.50%                                        
Debt instrument, maturity date   Feb. 01, 2019     Nov. 01, 2021   Oct. 06, 2016 Feb. 26, 2015                                  
Senior unsecured notes payment frequency     semi-annually   semi-annually                                        
Net proceeds from issuance of notes   390,000,000     393,400,000                                        
Redemption percentage, maximum                     35.00%     35.00%                      
Percentage of repurchase price to aggregate principal amount of notes repurchased plus any accrued and unpaid interest                   110.00% 107.25% 100.00% 103.625% 106.50% 100.00% 101.813% 100.00% 103.25% 102.167% 101.083% 100.00%        
Percentage of minimum outstanding principal amount                     65.00%     65.00%                      
Debt instrument covenant description   $10.0 million or more     $10.0 million or more 10.0 million                                      
Deferred financing cost       $ 8,600,000   $ 7,100,000 $ 2,800,000