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Summary of Significant Accounting Policies - Additional Information (Detail)
3 Months Ended
Mar. 31, 2017
USD ($)
Segment
Mar. 31, 2016
USD ($)
Dec. 31, 2016
USD ($)
Summary Of Significant Accounting Policies [Line Items]      
Accounts receivable $ 33,823,000   $ 44,423,000
Capitalized interest expense 400,000 $ 200,000  
Depreciation, depletion and amortization $ 26,189,000 15,113,000  
Impairment of oil and gas properties   $ 17,665,000  
Asset retirement obligations credit adjusted discount rates 10.33% 10.33%  
Operating lease expiration year 2024    
Number of operating segment | Segment 1    
Oil and Gas Properties [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Depreciation, depletion and amortization $ 25,700,000 $ 14,600,000  
Other property and equipment [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Depreciation $ 500,000 500,000  
Other property and equipment [Member] | Minimum [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Property and equipment, expected lives 5 years    
Other property and equipment [Member] | Maximum [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Property and equipment, expected lives 40 years    
Proved Oil And Gas Properties [Member] | Utica Shale [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Impairment of oil and gas properties $ 0 17,700,000  
Unproved Oil And Gas Properties [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Impairment of oil and gas properties 4,100,000 $ 9,400,000  
Commodity Contract [Member] | Not Designated as Hedging Instrument [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Fair value of commodity derivative contracts (22,700,000)   (48,100,000)
Unbilled Revenues [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Accounts receivable $ 32,500,000   $ 41,400,000