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Debt - Additional Information (Details) - USD ($)
1 Months Ended 3 Months Ended 7 Months Ended
Feb. 28, 2018
Mar. 31, 2019
Mar. 31, 2018
May 11, 2017
Oct. 04, 2016
Debt Instrument          
Repayments of borrowings   $ 19,596,000 $ 36,304,000    
Gain on extinguishment of debt   0 1,151,000    
Credit Facility | Revolving Credit Facility          
Debt Instrument          
Maximum borrowing capacity   600,000,000.0      
Borrowing base   $ 350,000,000.0      
Commitment fee   0.50%      
Percentage of proved reserves pledged as collateral   95.00%      
Total net leverage ratio (no greater than)   3.50      
Interest coverage ratio (no less than)   2.25      
Leverage ratio   0.06      
Coverage ratio   80.20      
Aggregate principal amount of default trigger   $ 25,000,000.0      
Default trigger related to judgment liability   25,000,000.0      
Debt outstanding   20,000,000.0      
Outstanding letters of credit   $ 5,200,000      
Credit Facility | Revolving Credit Facility | Minimum | LIBOR          
Debt Instrument          
Basis spread on variable rate   3.00%      
Credit Facility | Revolving Credit Facility | Minimum | Base Rate          
Debt Instrument          
Basis spread on variable rate   2.00%      
Credit Facility | Revolving Credit Facility | Maximum | LIBOR          
Debt Instrument          
Basis spread on variable rate   4.00%      
Credit Facility | Revolving Credit Facility | Maximum | Base Rate          
Debt Instrument          
Basis spread on variable rate   3.00%      
New Building Note | Secured Notes          
Debt Instrument          
Repayments of borrowings $ 36,300,000        
Face amount of debt instrument         $ 35,000,000.0
Interest costs paid-in-kind       $ 1,300,000  
Gain on extinguishment of debt     $ 1,200,000