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v3.3.1.900

Summary of Significant Accounting Policies Other (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($) | Dec. 31, 2013 USD ($)
Basis of Presentation and Significant Accounting Policies [Line Items] |  |  |  |
Receivables Collection Period |  | 2 months |  |
Allowance for Doubtful Accounts Receivable |  | $ 1,100 | $ 0 |
Capitalized Computer Software, Gross |  | $ 44,000 | 35,000 |
Concentration of Credit Risk and Major Customers [Abstract] |  |  |  |
Marketing agreement length for gathering, transportation, and processing through-put commitments |  | 10 years |  |
Number of Derivative Counterparties |  | 10 |  |
Revenues [Abstract] |  |  |  |
Revenue Receipt, Days After Sale, Low End of Range |  | 30 days |  |
Revenue Receipt, Days After Sale, High End of Range |  | 90 days |  |
Impairment of Proved, Unproved, and Other Properties [Abstract] |  |  |  |
Period of New York Mercantile Exchange Strip Pricing Used for Price Forecast |  | 5 years |  |
Impairment of proved properties |  | $ 468,679 | 84,480 | $ 172,641
Abandonment and impairment of unproved properties |  | 78,643 | 75,638 | 46,105
Impairment of other property and equipment |  | 49,369 | 0 | $ 0
Line of Credit [Member] |  |  |  |
Basis of Presentation and Significant Accounting Policies [Line Items] |  |  |  |
Revolving credit facility | [1] | $ 202,000 | $ 166,000 |
Customer Concentration Risk [Member] | Oil And Gas Sales Revenue [Member] |  |  |  |
Concentration of Credit Risk and Major Customers [Abstract] |  |  |  |
Number of Major Customers |  | 1 | 1 | 3
Customer Concentration Risk [Member] | Oil And Gas Sales Revenue [Member] | Major Customer One [Member] |  |  |  |
Concentration of Credit Risk and Major Customers [Abstract] |  |  |  |
Entity-Wide Revenue, Major Customer, Percentage |  | 21.00% | 19.00% | 16.00%
Customer Concentration Risk [Member] | Oil And Gas Sales Revenue [Member] | Major Customer Two [Member] |  |  |  |
Concentration of Credit Risk and Major Customers [Abstract] |  |  |  |
Entity-Wide Revenue, Major Customer, Percentage |  |  |  | 26.00%
Customer Concentration Risk [Member] | Oil And Gas Sales Revenue [Member] | Major Customer Three [Member] |  |  |  |
Concentration of Credit Risk and Major Customers [Abstract] |  |  |  |
Entity-Wide Revenue, Major Customer, Percentage |  |  |  | 12.00%
Customer Concentration Risk [Member] | Oil And Gas Sales Revenue [Member] | Unnamed Major Customer One with Related Entities [Member] |  |  |  |
Concentration of Credit Risk and Major Customers [Abstract] |  |  |  |
Entity-Wide Revenue, Major Customer, Percentage |  | 10.00% | 14.00% |
Number of Entities Related to One Unnamed Customer |  | 4 |  |
Customer Concentration Risk [Member] | Oil And Gas Sales Revenue [Member] | Unnamed Major Customer Two with Related Entities [Member] |  |  |  |
Concentration of Credit Risk and Major Customers [Abstract] |  |  |  |
Entity-Wide Revenue, Major Customer, Percentage |  | 11.00% |  |
Number of Entities Related to One Unnamed Customer |  | 3 |  |
Oil and Gas Properties [Member] |  |  |  |
Property, Plant and Equipment [Abstract] |  |  |  |
Property, Plant, and Equipment, Salvage Value |  | $ 29,700 | $ 50,800 |
Minimum [Member] | Property, Plant and Equipment, Other Types [Member] |  |  |  |
Inventory, Net [Abstract] |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives |  | 3 |  |
Maximum [Member] | Property, Plant and Equipment, Other Types [Member] |  |  |  |
Inventory, Net [Abstract] |  |  |  |
Property, Plant and Equipment, Estimated Useful Lives |  | 30 |  |
[1] | Deferred financing costs attributable to the credit facility are presented as a component of other noncurrent assets on the accompanying balance sheets and thus are not deducted from the credit facility balance.

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