Quarterly report pursuant to Section 13 or 15(d)

DERIVATIVE INSTRUMENTS AND PRICE RISK MANAGEMENT - Gain (Loss) on Derivative Instruments and Commodity Swap Contracts (Details)

v3.19.1
DERIVATIVE INSTRUMENTS AND PRICE RISK MANAGEMENT - Gain (Loss) on Derivative Instruments and Commodity Swap Contracts (Details)
$ in Thousands
3 Months Ended
Mar. 31, 2019
USD ($)
$ / bbl
bbl
Mar. 31, 2018
USD ($)
Non-cash gains or losses on derivative contracts [Abstract]    
Cash Received (Paid) on Settled Derivatives | $ $ 12,546 $ (8,130)
Non-Cash Mark-to-Market Gain (Loss) on Derivatives | $ (152,169) (12,141)
Gain (Loss) on Derivative Instruments, Net | $ $ (139,623) $ (20,271)
Total Open Commodity Swaps    
Non-cash gains or losses on derivative contracts [Abstract]    
Oil (in barrels) | bbl 14,800,000  
Weighted average price (in dollars per barrel) | $ / bbl 60.50  
2019    
Non-cash gains or losses on derivative contracts [Abstract]    
Oil (in barrels) | bbl 5,535,030  
Weighted average price (in dollars per barrel) | $ / bbl 63.16  
2020    
Non-cash gains or losses on derivative contracts [Abstract]    
Oil (in barrels) | bbl 6,428,580  
Weighted average price (in dollars per barrel) | $ / bbl 59.29  
2021    
Non-cash gains or losses on derivative contracts [Abstract]    
Oil (in barrels) | bbl 2,678,850  
Weighted average price (in dollars per barrel) | $ / bbl 58.16  
2022 and beyond    
Non-cash gains or losses on derivative contracts [Abstract]    
Oil (in barrels) | bbl 135,000  
Weighted average price (in dollars per barrel) | $ / bbl 55.00  
Basis Swap Contracts    
Non-cash gains or losses on derivative contracts [Abstract]    
Oil (in barrels) | bbl 2,841,000  
Weighted average price (in dollars per barrel) | $ / bbl 2.42