Property Acquisitions and Divestitures - Narrative (Details)
3 Months Ended 12 Months Ended
Mar. 02, 2018
USD ($)
a
Wells
Feb. 08, 2018
USD ($)
a
Jun. 08, 2017
USD ($)
a
Wells
Dec. 31, 2018
USD ($)
Dec. 31, 2019
USD ($)
a
Dec. 31, 2018
USD ($)
Dec. 31, 2017
USD ($)
Business Acquisition [Line Items]              
Acquisition of oil and natural gas properties         $ 103,709,000 $ 212,513,000 $ 435,547,000
Allocated to unproved properties       $ 1,680,065,000 1,470,903,000 1,680,065,000  
Allocated to proved properties       2,895,280,000 3,962,175,000 2,895,280,000  
Proceeds from sale of undeveloped acres         $ 34,730,000 148,149,000 $ 22,496,000
Northern Delaware Basin              
Business Acquisition [Line Items]              
Undeveloped net acres acquired | a   4,000          
Acquisition of oil and natural gas properties   $ 94,700,000 $ 350,100,000        
Gas and oil area, average working interest percentage   92.00%          
Settlement adjustments           300,000  
Net purchase price of undeveloped acres           182,300,000  
Allocated to unproved properties     296,900,000 142,500,000   142,500,000  
Allocated to proved properties     53,200,000 39,800,000   39,800,000  
Transaction costs     $ 500,000 200,000   $ 200,000  
Number of horizontal wells acquired (in wells) | Wells     36        
Gas and oil area, area offset by existing acreage (in acres) | a     11,850        
Gas and oil area, gross offset existing acreage (in acres) | a     14,770        
Gas and oil area, operated by company, percent     79.00%        
Gas and oil area, working interest, percent     85.00%        
Lea County, New Mexico and Reeves County              
Business Acquisition [Line Items]              
Undeveloped net acres acquired | a         2,900    
Acquisition of oil and natural gas properties       $ 87,900,000      
Reeves County              
Business Acquisition [Line Items]              
Undeveloped net acres acquired | a 8,600            
Number wells sold (in wells) | Wells 12            
Proceeds from sale of undeveloped acres $ 140,700,000            
Average working interest percentage 32.00%            
Gain (loss) on sale of oil and gas properties $ 0            
Previously Reported [Member] | Northern Delaware Basin              
Business Acquisition [Line Items]              
Acquisition of oil and natural gas properties     $ 350,000,000.0        
Restatement Adjustment [Member] | Northern Delaware Basin              
Business Acquisition [Line Items]              
Acquisition of oil and natural gas properties     $ 100,000