Fair Value Measurements (Fair Value of Financial Liabilities Measured on Recurring Basis) (Details) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Derivative liability	$ 185,000	$ 292,000
Total liabilities	185,000	292,000
November 2016 Warrants [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Derivative liability	157,000	260,000
June 2016 Offering Liability [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Derivative liability	28,000	32,000
Fair Value, Inputs, Level 1 [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Total liabilities
Fair Value, Inputs, Level 1 [Member] | November 2016 Warrants [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Derivative liability
Fair Value, Inputs, Level 1 [Member] | June 2016 Offering Liability [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Derivative liability
Fair Value, Inputs, Level 2 [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Total liabilities
Fair Value, Inputs, Level 2 [Member] | November 2016 Warrants [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Derivative liability
Fair Value, Inputs, Level 2 [Member] | June 2016 Offering Liability [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Derivative liability
Fair Value, Inputs, Level 3 [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Total liabilities	185,000	292,000
Fair Value, Inputs, Level 3 [Member] | November 2016 Warrants [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Derivative liability	157,000	260,000
Fair Value, Inputs, Level 3 [Member] | June 2016 Offering Liability [Member]
Schedule Of Derivative Liabilities At Fair Value [Line Items]
Derivative liability	$ 28,000	$ 32,000