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Contingencies - Narrative (Details) |  |  | 1 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jul. 29, 2016 defendant | Feb. 09, 2016 defendant | Sep. 30, 2014 USD ($) | Jul. 29, 2016 claim | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($) | Dec. 31, 2014 USD ($)
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Number of new claims filed | claim |  |  |  | 2 |  |  |
Amount of settlement litigation against |  |  | $ (18,000,000) |  |  |  |
Insurance proceeds |  |  |  |  | $ (5,718,000) | $ (10,015,000) | $ 0
Uninsured cash amount |  |  |  |  | 1,500,000,000 |  |
Maximum |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Cash, FDIC insured amount |  |  |  |  | $ 250,000 |  |
Judicial District Court for the Parish of Cameron |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Number of defendants | defendant |  | 26 |  |  |  |  |
Judicial District Court for the Parish of Vermillion |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Number of defendants | defendant | 40 |  |  |  |  |  |
Customer concentration risk | Capacity | British Petroleum | Natural gas, per MMbtu |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Percentage of total production sold by customer |  |  |  |  | 68.00% | 79.00% | 40.00%
Customer concentration risk | Capacity | DTE Energy Trading Inc | Natural gas, per MMbtu |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Percentage of total production sold by customer |  |  |  |  | 10.00% | 14.00% | 32.00%
Customer concentration risk | Capacity | Shell Trading Company | Oil derivatives |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Percentage of total production sold by customer |  |  |  |  | 72.00% | 90.00% | 99.00%
Customer concentration risk | Capacity | Marathon Oil Corporation | Oil derivatives |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Percentage of total production sold by customer |  |  |  |  | 24.00% | 10.00% |
Customer concentration risk | Capacity | Markwest Utica |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Percentage of total production sold by customer |  |  |  |  |  |  | 100.00%
Customer concentration risk | Capacity | Markwest Utica | Natural gas liquids |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Percentage of total production sold by customer |  |  |  |  | 74.00% | 76.00% |
Customer concentration risk | Capacity | Antero Resources | Natural gas liquids |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Percentage of total production sold by customer |  |  |  |  | 23.00% | 24.00% |
Customer concentration risk | Capacity | Hess | Natural gas, per MMbtu |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |
Percentage of total production sold by customer |  |  |  |  |  |  | 19.00%

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