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Stock- Based Compensation (Details) (USD $) | 6 Months Ended | 1 Months Ended
--- | --- | ---
Jun. 30, 2014 | Jun. 30, 2013 | May 31, 2014 Deferred Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award Non Option Equity Instruments Granted Per Director (in shares) |  |  | 212
Expense recognized in connection with the issuance of Deferred Stock Units (in US dollars) | $ 394,000 | $ 394,000 | $ 394,000
Expense per grant recognized in connection with the issuance of Deferred Stock Units (in US dollars) |  |  | $ 56,250

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