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Oil and Natural Gas Properties - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Oil And Natural Gas Properties [Line Items]    
Accumulated impairments to proved and unproved oil and natural gas properties $ 121.1 $ 121.1
Proved Oil and Natural Gas Properties    
Oil And Natural Gas Properties [Line Items]    
Depletion expenses $ 68.5 47.1
Unproved Oil and Gas Properties | Minimum    
Oil And Natural Gas Properties [Line Items]    
Unproved oil and gas lease term 3 years  
Unproved Oil and Gas Properties | Maximum    
Oil And Natural Gas Properties [Line Items]    
Unproved oil and gas lease term 5 years  
Eagle Ford Trend Properties    
Oil And Natural Gas Properties [Line Items]    
Accumulated impairments to proved and unproved oil and natural gas properties   $ 4.6