Derivative Instruments (Derivative instruments recorded on the balance sheet at fair value) (Detail) - USD ($)
$ in Thousands
Mar. 31, 2017
Mar. 21, 2017
Dec. 31, 2016
Dec. 31, 2015
Fair value of derivative instruments        
Derivative assets, gross $ 19,908      
Derivative liabilities, gross (363)      
Derivative assets (liabilities), net 19,545      
Netting adjustments [1] 363      
Derivative Liability, Netting adjustments [1] (363)      
Current derivative assets, net 10,001 $ 19,058    
Current derivative liabilities, net 0      
Current derivative assets (liabilities), net 10,001      
Long-term derivative assets, net 9,544 14,295    
Long-term derivative liabilities, net 0      
Long-term derivative assets (liabilities), net 9,544      
Predecessor        
Fair value of derivative instruments        
Derivative assets, gross     $ 184 $ 164,396
Derivative liabilities, gross     (13,553) (1,158)
Derivative assets (liabilities), net     (13,369) 163,238
Netting adjustments     184 [1] 1,158 [2]
Derivative Liability, Netting adjustments     (184) [1] (1,158) [2]
Current derivative assets, net   19,058 0 143,737
Current derivative liabilities, net     (7,525) 0
Current derivative assets (liabilities), net     (7,525) 143,737
Long-term derivative assets, net   $ 14,295 0 19,501
Long-term derivative liabilities, net     (5,844) 0
Long-term derivative assets (liabilities), net     (5,844) 19,501
Natural Gas Derivative Contracts        
Fair value of derivative instruments        
Derivative assets, gross 634      
Derivative liabilities, gross (363)      
Derivative assets (liabilities), net 271      
Natural Gas Derivative Contracts | Predecessor        
Fair value of derivative instruments        
Derivative assets, gross     184 41,328
Derivative liabilities, gross     (3,658) (1,158)
Derivative assets (liabilities), net     (3,474) 40,170
Crude Oil Derivative Contracts        
Fair value of derivative instruments        
Derivative assets, gross 19,274      
Derivative assets (liabilities), net $ 19,274      
Crude Oil Derivative Contracts | Predecessor        
Fair value of derivative instruments        
Derivative assets, gross       123,068
Derivative liabilities, gross     (9,895)  
Derivative assets (liabilities), net     $ (9,895) $ 123,068
[1] Amounts represent the impact of master netting agreements that allow us to net settle positive and negative positions with the same counterparty. Positive and negative positions with counterparties are netted only to the extent that they relate to the same current versus noncurrent classification on the balance sheet.
[2] Amounts represent the impact of master netting agreements that allow us to net settle positive and negative positions with the same counterparty. Positive and negative positions with a counterparty are netted only to the extent that they related to the same current versus noncurrent classification on the balance sheet.