Quarterly report pursuant to Section 13 or 15(d)

Derivative Instruments and Hedging Activities (Schedule of Outstanding Oil and Natural Gas Derivative Contracts) (Details)

v3.8.0.1
Derivative Instruments and Hedging Activities (Schedule of Outstanding Oil and Natural Gas Derivative Contracts) (Details) - Forecast - Not Designated as Hedging Instrument
9 Months Ended 12 Months Ended
Dec. 31, 2018
MMBTU
$ / MMBTU
MBbls
Dec. 31, 2019
MMBTU
$ / MMBTU
MBbls
Oil | Swap contracts    
Derivative [Line Items]    
Total volume (MBbls) | MBbls 1,559,000 0
Average swap price (in dollars per share) 51.88 0.00
Oil | Collar contracts (two-way collars)    
Derivative [Line Items]    
Total volume (MBbls) | MBbls 275,000 0
Oil | Collar contracts (two-way collars) | Call option | Short    
Derivative [Line Items]    
Strike price (in dollars per share) 60.50 0
Oil | Collar contracts (two-way collars) | Put option | Long    
Derivative [Line Items]    
Strike price (in dollars per share) 50 0
Oil | Collar contracts combined with short puts (three-way collars)    
Derivative [Line Items]    
Total volume (MBbls) | MBbls 2,612,000 2,739,000
Oil | Collar contracts combined with short puts (three-way collars) | Call option | Short    
Derivative [Line Items]    
Strike price (in dollars per share) 60.86 62.96
Oil | Collar contracts combined with short puts (three-way collars) | Put option | Short    
Derivative [Line Items]    
Strike price (in dollars per share) 39.21 43.67
Oil | Collar contracts combined with short puts (three-way collars) | Put option | Long    
Derivative [Line Items]    
Strike price (in dollars per share) 48.95 53.67
Oil | Oil contracts (Midland basis differential) | Swap contracts    
Derivative [Line Items]    
Total volume (MBbls) | MBbls 3,895,000 0
Average swap price (in dollars per share) 0.86 0.00
Natural gas | Swap contracts | Swap contracts    
Derivative [Line Items]    
Total volume (BBtu) | MMBTU 4,125,000 0
Strike price (in dollars per share) 2.91 0