Fair Value of Financial Assets and Liabilities - Derivative Instruments (Fair Value of Financial Liabilities Measured on Recurring Basis) (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Preferred B stock conversion liability	$ 1,493,000	$ 12,320,000
Warrant liability	6,000	5,826,000
Total liabilities	1,499,000	18,146,000
Fair Value, Inputs, Level 3 [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Preferred B stock conversion liability	1,493,000	12,320,000
Warrant liability	6,000	5,826,000
Total liabilities	$ 1,499,000	$ 18,146,000