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Fair Value Measurements - Nonrecurring (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2020
Mar. 31, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Fair Value Measurements [Line Items]          
Proved Oil and Gas Properties, Carrying Value, Before Impairment   $ 1,700,000      
Unproved Oil and Gas Properties, Net Book Value Prior to Impairment   256,000      
Proved Oil and Gas Properties          
Fair Value Measurements [Line Items]          
Impairment of Oil and Gas Properties $ 0 1,200,000 $ 0 $ 1,188,566 $ 0
Proved Oil and Gas Properties | Level 3          
Fair Value Measurements [Line Items]          
Oil and Gas Property, Successful Effort Method, Net   500,000      
Unproved Oil and Gas Properties          
Fair Value Measurements [Line Items]          
Impairment of Oil and Gas Properties $ 0 76,300 $ 0 $ 76,298 $ 0
Unproved Oil and Gas Properties | Level 3          
Fair Value Measurements [Line Items]          
Oil and Gas Property, Successful Effort Method, Net   $ 179,700