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Acquisitions (Details) $ in Thousands |  |  |  |  |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Aug. 31, 2015 USD ($) | Jun. 29, 2015 USD ($) a | Jun. 12, 2015 USD ($) a well mi MMcf | Jun. 09, 2015 USD ($) a | Mar. 20, 2014 USD ($) | Jun. 29, 2015 USD ($) a | Apr. 30, 2015 USD ($) a | Dec. 31, 2014 USD ($) | Feb. 28, 2014 a
Rhino Exploration, LLC, Utica Shale Properties [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Purchase price |  |  |  |  |  |  |  | $ 182,000 |
Gas and oil acreage, net | a |  |  |  |  |  |  |  |  | 8,000
Cash, net of purchase price adjustments |  |  |  |  | $ 179,527 |  |  | $ 179,500 |
Fair value of net identifiable assets acquired |  |  |  |  | 179,527 |  |  |  |
Rhino Exploration, LLC, Utica Shale Properties [Member] | Proved Properties [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Fair value of net identifiable assets acquired |  |  |  |  | 31,961 |  |  |  |
Rhino Exploration, LLC, Utica Shale Properties [Member] | Unproved Properties [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Fair value of net identifiable assets acquired |  |  |  |  | 6,263 |  |  |  |
Rhino Exploration, LLC, Utica Shale Properties [Member] | Unevaluated Properties [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Fair value of net identifiable assets acquired |  |  |  |  | $ 141,303 |  |  |  |
Paloma Partners III, LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Purchase price | $ 302,300 |  |  |  |  |  | $ 301,900 |  |
Gas and oil acreage, net | a |  |  |  |  |  |  | 24,000 |  |
Amount put in escrow | $ 30,100 |  |  |  |  |  | $ 75,000 |  |
American Energy - Utica, LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Purchase price |  |  |  |  |  | $ 405,400 |  |  |
Amount put in escrow |  |  |  | $ 67,100 |  |  |  |  |
Cash, net of purchase price adjustments |  |  | $ 405,029 |  |  |  |  |  |
Fair value of net identifiable assets acquired |  |  | 405,029 |  |  |  |  |  |
American Energy - Utica, LLC [Member] | Proved Properties [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Fair value of net identifiable assets acquired |  |  | 70,804 |  |  |  |  |  |
American Energy - Utica, LLC [Member] | Unevaluated Properties [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Fair value of net identifiable assets acquired |  |  | 334,225 |  |  |  |  |  |
Belmont And Jefferson Counties, Ohio [Member] | American Energy - Utica, LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Purchase price |  |  |  | $ 68,200 |  |  |  |  |
Gross and net acres acquired | a |  |  |  | 6,198 |  |  |  |  |
Monroe County, Ohio [Member] | American Energy - Utica, LLC [Member] |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |
Purchase price |  | $ 18,200 | $ 319,000 |  |  |  |  |  |
Gas and oil acreage, gross | a |  | 4,950 | 38,965 |  |  | 4,950 |  |  |
Gas and oil acreage, net | a |  | 1,900 | 27,228 |  |  | 1,900 |  |  |
Daily production of well acquired | MMcf |  |  | 14.6 |  |  |  |  |  |
Gross wells acquired | well |  |  | 18 |  |  |  |  |  |
Net wells acquired | well |  |  | 11.3 |  |  |  |  |  |
Gas gathering system (in miles) | mi |  |  | 11 |  |  |  |  |  |
Number of well pad locations acquired | well |  |  | 4 |  |  |  |  |  |

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