Fair Value of Financial Assets and Liabilities - Derivative Instruments (Fair Value of Financial Liabilities Measured on Recurring Basis) (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Preferred B stock conversion liability		$ 1,493,000
Total liabilities	$ 2,443,000	1,499,000
Dilutive Financing Derivative Liability [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Derivative liability	126,000
November 2016 Warrant Derivative Liability [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Warrant liability	2,043,000
June 2016 Offering Warrants [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Warrant liability	274,000
2011 Warrants [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Warrant liability		6,000
Fair Value, Inputs, Level 3 [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Preferred B stock conversion liability		1,493,000
Total liabilities	2,443,000	1,499,000
Fair Value, Inputs, Level 3 [Member] | Dilutive Financing Derivative Liability [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Derivative liability	126,000
Fair Value, Inputs, Level 3 [Member] | November 2016 Warrant Derivative Liability [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Warrant liability	2,043,000
Fair Value, Inputs, Level 3 [Member] | June 2016 Offering Warrants [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Warrant liability	$ 274,000
Fair Value, Inputs, Level 3 [Member] | 2011 Warrants [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Warrant liability		$ 6,000