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Subsequent Events (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended | 0 Months Ended |
--- | --- | --- | ---
Dec. 31, 2013 MBoe | Dec. 31, 2012 MBoe | Feb. 15, 2013 Utica Shale [Member] | Dec. 21, 2012 Utica Shale [Member] | Dec. 18, 2012 Utica Shale [Member] | Dec. 19, 2012 Utica Shale [Member] | Feb. 26, 2014 Subsequent Event [Member] Utica Shale [Member] MBoe acre | Jan. 31, 2013 Subsequent Event [Member] Natural Gas Fixed Swap, May 2014 Through December 2015 [Member] Swap [Member] Gas [Member] MMBTU | Jan. 31, 2013 Subsequent Event [Member] Natural Gas Fixed Swap, June 2014 Through December 2015 [Member] Swap [Member] Gas [Member] MMBTU
Derivative [Line Items] |  |  |  |  |  |  |  |  |
Notional quantity |  |  |  |  |  |  |  | 25,000 | 25,000
Average fixed price |  |  |  |  |  |  |  | 4.20 | 4.21
Purchase commitment, for additional acreage |  |  |  |  |  |  | 8,200 |  |
Purchase commitment for additional BOEPD | 27,805,000 | 6,675,000 |  |  |  |  | 1,000 |  |
Purchase price commitment |  |  | $ 220.0 | $ 70.0 | $ 302.0 | $ 372.0 | $ 185.0 |  |

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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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