Accrued Expenses and Other Current Liabilities (Severance and Restructuring Accruals) (Narrative) (Details) - USD ($)			1 Months Ended	3 Months Ended		12 Months Ended
	Dec. 10, 2014	Sep. 17, 2014	Dec. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Sep. 30, 2014
Severance and restructuring accruals:
Outplacement services, value		$ 15,000
Payments to terminate lease agreement			$ 200,000	$ 200,000
Gain on lease termination			$ 300,000	$ 310,000	$ 0
Chief Executive Officer
Severance and restructuring accruals:
Estimated charge related to separation agreement						$ 800,000
Continuation of base salary period	602 days
Outplacement services, period		1 year
Outplacement services, value		$ 15,000
Chief Administrative Officer and Chief Counsel and Secretary
Severance and restructuring accruals:
Estimated charge related to separation agreement						$ 1,100,000
Outplacement services, period		1 year
Chief Administrative Officer
Severance and restructuring accruals:
Continuation of base salary period	518 days
Chief Counsel and Secretary
Severance and restructuring accruals:
Continuation of base salary period	476 days