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Acquisitions (Details) (USD $) | 3 Months Ended | 9 Months Ended | 0 Months Ended | 6 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013 | Mar. 20, 2014 Utica Shale [Member] | Feb. 15, 2013 Utica Shale [Member] well acre | Sep. 30, 2014 Utica Shale [Member] | Mar. 20, 2014 Utica Shale [Member] acre | Feb. 15, 2013 Utica Shale [Member] acre well | Mar. 20, 2014 Utica Shale [Member] Proved Properties [Member] | Mar. 20, 2014 Utica Shale [Member] Unproved Properties [Member] | Mar. 20, 2014 Utica Shale [Member] Unevaluated Properties [Member]
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gas and oil acreage, undeveloped, net |  |  |  |  |  |  |  | 8,000 | 22,000 |  |  |
Cash price of ownership interest |  |  |  |  | $ 184,000,000 | $ 220,000,000 |  |  |  |  |  |
Amount put in escrow |  |  |  |  |  |  |  |  | 33,600,000 |  |  |
Proceeds from issuance of common stock, net of offering costs and exercise of stock options |  |  | 654,000 | 359,040,000 |  | 325,800,000 |  |  |  |  |  |
Existing wells excluded |  |  |  |  |  |  |  |  | 14 |  |  |
Future wells excluded |  |  |  |  |  | 16 |  |  |  |  |  |
Purchase price |  |  |  |  | 179,000,000 |  |  |  |  |  |  |
Cash, net of purchase price adjustments |  |  |  |  | 177,444,000 |  |  |  |  |  |  |
Net revenues | 170,804,000 | 69,252,000 | 403,569,000 | 194,686,000 |  |  | 4,900,000 |  |  |  |  |
Lease operating expenses | 11,883,000 | 7,297,000 | 36,192,000 | 18,347,000 |  |  | 700,000 |  |  |  |  |
Fair value of net identifiable assets acquired |  |  |  |  |  |  |  | $ 177,444,000 |  | $ 32,005,000 | $ 6,263,000 | $ 139,176,000

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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7488404&loc=d3e6927-128479 + 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=6910749&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=25498275&loc=d3e2207-128464 + Details
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- Definition The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Fractional interest owned based on working interests or other economic arrangements of lease area on which wells have not been drilled or completed to a point that would permit the production of commercial quantities of oil and gas regardless of whether or not such area contains proved reserves. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Industry Guide -Number 2 -Paragraph 5 + Details
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- Definition The cash outflow to purchase long lived physical asset for use in the normal oil and gas operations and to purchase mineral interests in oil and gas properties not intended for resale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3213-108585 + Details
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