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Acquisitions - Fair Value of Assets Acquired (Details) - USD ($) $ in Thousands |  |  |  | 12 Months Ended
--- | --- | --- | --- | ---
Jun. 29, 2015 | Jun. 12, 2015 | Mar. 20, 2014 | Dec. 31, 2015
American Energy - Utica, LLC |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Cash, net of purchase price adjustments | $ 405,000 | $ 405,029 |  |
Fair value of net identifiable assets acquired |  | 405,029 |  |
Utica Shale |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Cash, net of purchase price adjustments |  |  | $ 179,527 | $ 179,500
Fair value of net identifiable assets acquired |  |  | 179,527 |
Proved | American Energy - Utica, LLC |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Fair value of net identifiable assets acquired |  | 70,804 |  |
Proved | Utica Shale |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Fair value of net identifiable assets acquired |  |  | 31,961 |
Unproved | Utica Shale |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Fair value of net identifiable assets acquired |  |  | 6,263 |
Unevaluated | American Energy - Utica, LLC |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Fair value of net identifiable assets acquired |  | $ 334,225 |  |
Unevaluated | Utica Shale |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Fair value of net identifiable assets acquired |  |  | $ 141,303 |

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- Definition Payment to Acquire Oil and Gas Property and Equipment, Net + References No definition available. + Details
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- Definition The amount of property, plant, and equipment recognized as of the acquisition date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464 + Details
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