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Property, Plant and Equipment - Additional Information (Details)
 3 Months Ended 12 Months Ended
Dec. 31, 2020
USD ($)
Mar. 31, 2020
USD ($)
Dec. 31, 2020
USD ($)
$ / bbl
$ / Mcf
Dec. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Property, Plant and Equipment [Line Items]          
Write-down of oil and natural gas properties     $ 268,615,000 $ 12,386,000 $ 244,000
Write-down of oil and natural gas properties $ 267,859,000 $ 57,000 267,916,000 12,221,000  
Block 2          
Property, Plant and Equipment [Line Items]          
Write-down of oil and natural gas properties     100,000 $ 12,200,000  
US          
Property, Plant and Equipment [Line Items]          
Write-down of oil and natural gas properties     $ 267,900,000    
Unweighted average first day of month commodity price for crude oil for prior twelve months | $ / bbl     39.47    
Unweighted average first day of month commodity price for natural gas for prior twelve months | $ / Mcf     1.97    
Unweighted average first day of month commodity price for natural gas liquids for prior twelve months | $ / bbl     9.89    
Measurement Input Discount Rate          
Property, Plant and Equipment [Line Items]          
Present value of future net revenues from proved reserves, discount rate     10.00%