Annual report pursuant to Section 13 and 15(d)

Property and Equipment, Net (Narrative) (Details)

v3.20.4
Property and Equipment, Net (Narrative) (Details)
3 Months Ended 12 Months Ended
Mar. 31, 2021
$ / Boe
Mar. 31, 2021
USD ($)
Dec. 31, 2020
USD ($)
Sep. 30, 2020
USD ($)
Jun. 30, 2020
USD ($)
Dec. 31, 2021
bbl
Dec. 31, 2020
USD ($)
$ / Boe
Dec. 31, 2019
USD ($)
$ / Boe
Dec. 31, 2018
USD ($)
$ / Boe
Dec. 31, 2017
$ / Boe
Property, Plant and Equipment [Line Items]                    
Internal costs capitalized, Oil and Gas producing activities             $ 36,200,000   $ 28,000,000.0  
Capitalized interest             88,600,000 $ 78,500,000 56,200,000  
Impairment of evaluated oil and gas properties     $ 585,800,000 $ 685,000,000.0 $ 1,300,000,000   $ 2,547,241,000 $ 0 $ 0  
Average 12-month price, net of differentials | $ / Boe             37.44 53.90 58.40 49.48
Impairment of leasehold             $ 229,600,000      
Commodity - Oil                    
Property, Plant and Equipment [Line Items]                    
Average 12-month price, net of differentials | $ / Boe             37.44 53.90 58.40  
Forecast                    
Property, Plant and Equipment [Line Items]                    
Impairment of evaluated oil and gas properties   $ 100,000,000.0                
Average 12-month price, net of differentials | $ / Boe 40.23                  
Forecast | Commodity - Oil | Not Designated as Hedging Instrument | Short                    
Property, Plant and Equipment [Line Items]                    
Total volume (Bbls) | bbl           4,825,300        
Forecast | Commodity - Oil | Swap contracts | Not Designated as Hedging Instrument                    
Property, Plant and Equipment [Line Items]                    
Total volume (Bbls) | bbl           1,827,000