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Common Stock Options, Warrants And Changes In Capitalization (Details) (USD $) In Thousands, except Share data, unless otherwise specified | 12 Months Ended |  | 0 Months Ended |  |  | 1 Months Ended |  | 0 Months Ended |  |  | 96 Months Ended |  |  |  |
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Mar. 31, 2012 | Feb. 15, 2013 Utica Shale [Member] acre | Dec. 24, 2012 Utica Shale [Member] acre | Dec. 19, 2012 Utica Shale [Member] acre | Dec. 17, 2012 Utica Shale [Member] acre | Mar. 31, 2002 Private Placement [Member] | Dec. 31, 2012 Private Placement [Member] | Nov. 13, 2013 Common Stock [Member] Public Offering [Member] | Feb. 15, 2013 Common Stock [Member] Public Offering [Member] | Jan. 07, 2013 Common Stock [Member] Public Offering [Member] | Dec. 24, 2012 Common Stock [Member] Public Offering [Member] | Dec. 05, 2011 Common Stock [Member] Public Offering [Member] | Jul. 15, 2011 Common Stock [Member] Public Offering [Member] | Mar. 30, 2011 Common Stock [Member] Public Offering [Member] | Dec. 31, 2013 1999 Stock Option Plan [Member] Common Stock [Member] | Dec. 31, 2012 1999 Stock Option Plan [Member] Common Stock [Member] | Dec. 31, 2012 2005 Stock Incentive Plan [Member] Common Stock [Member] | Apr. 20, 2006 2005 Stock Incentive Plan [Member] Common Stock [Member] | Apr. 19, 2006 2005 Stock Incentive Plan [Member] Common Stock [Member] | Apr. 19, 2013 2013 Restated Stock Incentive Plan [Member] Common Stock [Member] | Apr. 20, 2006 2013 Restated Stock Incentive Plan [Member] Common Stock [Member]
Common Stock Options, Restricted Stock, Warrants And Changes In Capitalization [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 883,000 |  |  | 3,000,000 | 1,904,606 | 7,500,000 | 3,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Aggregate Options Granted |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 627,337 | 627,337 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 997,269 |  |  |  |
Issuance of common stock in public offering (shares) |  |  |  |  |  |  |  |  |  |  | 7,475,000 | 8,912,500 |  | 11,750,000 | 4,600,000 | 3,450,000 | 2,760,000 |  |  |  |  |  |  |
Stock option, portion available to underwriters (shares) |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,650,000 |  |  |  |  |  |  |  |  |  |
Stock option, portion attributable to underwriters (shares) |  |  |  |  |  |  |  |  |  |  |  |  | 900,000 | 750,000 |  |  |  |  |  |  |  |  |  |
Share price (usd per share) |  |  |  |  |  |  |  |  |  |  | $ 56.75 | $ 38.00 |  | $ 38.00 | $ 29.00 | $ 28.75 | $ 32.00 |  |  |  |  |  |  |
Proceeds from issuance of common stock, net of offering costs | $ 766,495 | $ 427,091 | $ 307,154 |  | $ 325,800 | $ 460,700 |  |  |  |  | $ 408,000 | $ 325,800 |  | $ 460,700 | $ 128,000 | $ 94,700 | $ 84,300 |  |  |  |  |  |  |
Private Placement Units Offered |  |  |  |  |  |  |  |  | 10,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right Number of Securities Called by Each Warrant or Right |  |  |  |  |  |  |  |  | 250 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, par value (usd per share) | $ 0.01 | $ 0.01 |  |  |  |  |  |  | $ 0.01 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock dividend rate | 12.00% | 12.00% |  |  |  |  |  |  | 15.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred Stock, Dividend Rate, Stock, Percentage |  |  |  |  |  |  |  |  | 12.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right, Outstanding |  |  |  |  |  |  |  |  | 2,322,962 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Term Of Warrants Expiration |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Warrant or Right, Exercise Price of Warrants or Rights |  |  |  |  |  |  |  |  |  | 1.19 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gas and oil acreage, undeveloped, net |  |  |  |  | 22,000 | 37,000 | 7,000 | 30,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class Of Warrant Or Right, Expired |  |  |  | 8,875 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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