Annual report pursuant to Section 13 and 15(d)

Derivative Instruments - Commodity derivatives (Details)

v3.19.3.a.u2
Derivative Instruments - Commodity derivatives (Details)
$ in Thousands
12 Months Ended
Dec. 31, 2019
USD ($)
MMBTU / d
$ / bbl
$ / MMBTU
$ / gal
bbl
Dec. 31, 2018
USD ($)
Commodity derivative    
Derivative Instruments    
Gross amounts on balance sheet | $ $ 882,817 $ 658,830
Swaps | NYMEX | Year ending December 31, 2020    
Derivative Instruments    
Weighted average index price | $ / bbl 2.87  
Swaps | NYMEX | Year ending December 31, 2021    
Derivative Instruments    
Weighted average index price | $ / MMBTU 2.80  
Swaps | NYMEX | Year ending December 31, 2023    
Derivative Instruments    
Weighted average index price | $ / MMBTU 2.91  
Swaps | ARA Propane | Year ending December 31, 2020    
Derivative Instruments    
Weighted average index price | $ / gal 0.65  
Swaps | FEI Propane | Three months ending March 31, 2020    
Derivative Instruments    
Weighted average index price | $ / MMBTU 0.81  
Swaps | Mont Belvieu Butane Non-TET | Three months ending March 31, 2020    
Derivative Instruments    
Weighted average index price | $ / gal 0.50  
Swaps | Mont Belvieu Propane Non-TET | Three months ending March 31, 2020    
Derivative Instruments    
Weighted average index price | $ / gal 0.58  
Swaps | NYMEX-WTI | Year ending December 31, 2020    
Derivative Instruments    
Weighted average index price | $ / gal 55.63  
Swaps | Natural gas | Year ending December 31, 2020    
Derivative Instruments    
Notional amount (MMBtu/day) | MMBTU / d 2,227,500  
Swaps | Natural gas | NYMEX | Year ending December 31, 2020    
Derivative Instruments    
Notional amount (MMBtu/day) | MMBTU / d 2,227,500  
Swaps | Natural gas | NYMEX | Year ending December 31, 2021    
Derivative Instruments    
Notional amount (MMBtu/day) | MMBTU / d 2,400,000  
Swaps | Natural gas | NYMEX | Year ending December 31, 2023    
Derivative Instruments    
Notional amount (MMBtu/day) | MMBTU / d 90,000  
Swaps | Natural gas liquids    
Derivative Instruments    
Notional amount 18,800  
Swaps | Natural gas liquids | Three months ending March 31, 2020    
Derivative Instruments    
Notional amount 17,383  
Swaps | Natural gas liquids | Year ending December 31, 2020    
Derivative Instruments    
Notional amount 10,371  
Swaps | Natural gas liquids | ARA Propane | Year ending December 31, 2020    
Derivative Instruments    
Notional amount 10,371  
Swaps | Natural gas liquids | FEI Propane | Three months ending March 31, 2020    
Derivative Instruments    
Notional amount 9,883  
Swaps | Natural gas liquids | Mont Belvieu Butane Non-TET | Three months ending March 31, 2020    
Derivative Instruments    
Notional amount 6,000  
Swaps | Natural gas liquids | Mont Belvieu Propane Non-TET | Three months ending March 31, 2020    
Derivative Instruments    
Notional amount 1,500  
Swaps | Oil | Year ending December 31, 2020    
Derivative Instruments    
Notional amount 26,000  
Swaps | Oil | NYMEX-WTI | Year ending December 31, 2020    
Derivative Instruments    
Notional amount 26,000