Quarterly report pursuant to Section 13 or 15(d)

Long-Term Debt (Details)

v3.5.0.2
Long-Term Debt (Details) - USD ($)
$ in Thousands
6 Months Ended
Jun. 30, 2016
Dec. 31, 2015
Mar. 17, 2015
Sep. 18, 2014
May 06, 2014
Nov. 05, 2013
Feb. 04, 2013
Nov. 19, 2012
Long- term Debt                
Net unamortized premium $ 5,974 $ 6,513            
Net unamortized debt issuance costs (36,960) (39,731)            
Long-term debt 4,244,014 4,668,782            
Midstream Credit Facility Member                
Long- term Debt                
Bank credit facility long-term debt 760,000 $ 620,000            
Maximum amount of the Credit Facility $ 1,500,000              
Weighted average interest rate (as a percent) 1.96% 1.92%            
Midstream Credit Facility Member | Minimum                
Long- term Debt                
Commitment fees on the unused portion (as a percent) 0.25%              
Midstream Credit Facility Member | Maximum                
Long- term Debt                
Commitment fees on the unused portion (as a percent) 0.375%              
Bank credit facility                
Long- term Debt                
Bank credit facility long-term debt $ 140,000 $ 707,000            
Current borrowing base 4,500,000              
Lender commitments $ 4,000,000              
Weighted average interest rate (as a percent) 2.00% 2.32%            
Outstanding letters of credit $ 708,000 $ 702,000            
Bank credit facility | Minimum                
Long- term Debt                
Commitment fees on the unused portion (as a percent) 0.375%              
Bank credit facility | Maximum                
Long- term Debt                
Commitment fees on the unused portion (as a percent) 0.50%              
6.00% senior notes due 2020                
Long- term Debt                
Long-term notes payable $ 525,000 525,000            
Interest rate (as a percent)               6.00%
Senior notes issued             $ 225,000 $ 300,000
Issue price as percentage of par value             103.00% 100.00%
Redemption price 104.50%              
Percentage of principal amount at which notes may be required to be repurchased in event of change of control 101.00%              
6.00% senior notes due 2020 | On or after December 1, 2018                
Long- term Debt                
Redemption price 100.00%              
5.375% senior notes due 2021                
Long- term Debt                
Long-term notes payable $ 1,000,000 1,000,000            
Interest rate (as a percent)           5.375%    
Senior notes issued           $ 1,000,000    
Issue price as percentage of par value           100.00%    
Percentage of principal amount at which notes may be required to be repurchased in event of change of control 101.00%              
5.375% senior notes due 2021 | On or after November 1, 2016                
Long- term Debt                
Redemption price 104.031%              
5.375% senior notes due 2021 | On or after November 1, 2019                
Long- term Debt                
Redemption price 100.00%              
5.375% senior notes due 2021 | On or before November 1, 2016                
Long- term Debt                
Redemption price 100.00%              
Percentage of the principal amount of the debt instrument which the entity may redeem with the proceeds from certain equity offerings 35.00%              
Redemption price of the debt instrument if redeemed with the proceeds of certain equity offerings (as a percent) 105.375%              
Stand-alone revolving note                
Long- term Debt                
Maximum amount of the Credit Facility $ 25,000              
Outstanding balance $ 0 0            
Stand-alone revolving note | Lender's Prime Rate                
Long- term Debt                
Basis spread on variable rate (as a percent) 1.00%              
5.125% senior notes due 2022                
Long- term Debt                
Long-term notes payable $ 1,100,000 1,100,000            
Interest rate (as a percent)         5.125%      
Senior notes issued       $ 500,000 $ 600,000      
Issue price as percentage of par value       100.50% 100.00%      
Percentage of principal amount at which notes may be required to be repurchased in event of change of control 101.00%              
5.125% senior notes due 2022 | On or after June 1, 2017                
Long- term Debt                
Redemption price 103.844%              
5.125% senior notes due 2022 | On or before June 1, 2017                
Long- term Debt                
Percentage of the principal amount of the debt instrument which the entity may redeem with the proceeds from certain equity offerings 35.00%              
Redemption price of the debt instrument if redeemed with the proceeds of certain equity offerings (as a percent) 105.125%              
5.125% senior notes due 2022 | Prior to June 1, 2017                
Long- term Debt                
Redemption price 100.00%              
5.125% senior notes due 2022 | On or after June 1, 2020                
Long- term Debt                
Redemption price 100.00%              
5.625% senior notes due 2023                
Long- term Debt                
Long-term notes payable $ 750,000 $ 750,000            
Interest rate (as a percent)     5.625%          
Senior notes issued     $ 750,000          
Issue price as percentage of par value     100.00%          
Percentage of principal amount at which notes may be required to be repurchased in event of change of control 101.00%              
5.625% senior notes due 2023 | On Or Before June 1, 2018                
Long- term Debt                
Percentage of the principal amount of the debt instrument which the entity may redeem with the proceeds from certain equity offerings 35.00%              
Redemption price of the debt instrument if redeemed with the proceeds of certain equity offerings (as a percent) 105.625%              
5.625% senior notes due 2023 | On Or After June 1, 2018                
Long- term Debt                
Redemption price 104.219%              
5.625% senior notes due 2023 | On Or After June 1, 2021                
Long- term Debt                
Redemption price 100.00%              
5.625% senior notes due 2023 | Prior To June 1, 2018                
Long- term Debt                
Redemption price 100.00%