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Preferred Shares and Tender Offer (Details) - USD ($) | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2015 | Jun. 30, 2015 | May. 17, 2015 | Dec. 31, 2014
Max Reimbursement to Acquiror |  | $ 500,000 |  |
Preferred Stock, Liquidation Preference, Value | $ 1,000 | 1,000 |  |
Payments of Stock Issuance Costs |  | 2,900,000 |  |
Payments of Stock Issuance Costs |  | $ 2,700,000 |  |
Common Stock, Par or Stated Value Per Share | $ 0.01 | $ 0.01 | $ 0.01 | $ 0.01
merger termination fee | $ 20,000,000 |  |  |
Preferred Stock [Member] |  |  |  |
Sale of Stock, Value of Shares Authorized for Transaction | $ 150,000,000 | $ 150,000,000 |  |
Convertible Preferred Stock, Conversion Price | $ 5.00 | $ 5.00 | $ 5.05 |

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