Fair Value of Financial Assets and Liabilities - Derivative Instruments (Tables)

12 Months Ended

Dec. 31, 2017

Derivatives And Fair Value [Line Items]

Financial Liabilities Measured at Fair Value

	Quoted Prices in
	Active Markets		Significant Other		Significant
	for Identical		Observable Inputs		Unobservable
	Items (Level 1)		(Level 2)		Inputs (Level 3)		Total
December 31, 2017
Liabilities
June 2016 offering warrant liability	$	-	$	-	$	32,000	$	32,000
November 2016 offering warrant liability		-		-		260,000		260,000
Total liabilities	$	-	$	-	$	292,000	$	292,000
December 31, 2016
Liabilities
June 2016 offering warrant liability	$	-	$	-	$	274,000	$	274,000
Dilutive financing derivative liability		-		-		126,000		126,000
November 2016 offering warrant liability		-		-		2,043,000		2,043,000
Total liabilities	$	-	$	-	$	2,443,000	$	2,443,000

Changes in Fair Value of Derivative Liability

The following table sets forth a summary of changes in the fair value of the Company's derivative liabilities:

	June 2016		Dilutive		November 2016
	Offering		Financing		Offering		Total
	Warrant		Derivative		Warrant		Derivative
	Liability		Liability		Liability		Liabilities
Balance, December 31, 2016	$	274,000	$	126,000	$	2,043,000	$	2,443,000
Changes in estimated fair value		(242,000)		(104,000)		(1,664,000)		(2,010,000)
Exercised warrants		-		-		(119,000)		(119,000)
Settlement of liability		-		(22,000)		-		(22,000)
Balance, December 31, 2017	$	32,000	$	-	$	260,000	$	292,000

November 2016 Warrant Derivative Liability [Member]

Derivatives And Fair Value [Line Items]

Valuation Assumptions Used

The assumptions used consisted of the following:

	December 31, 2017			December 31, 2016
Volatility		107	%		112	%
Expected term (years)		3.89			4.89
Risk-free interest rate		2.08	%		1.91	%
Dividend yield		0.00	%		0.00	%
Exercise price (1)		$0.57			$7.50
Common stock closing price		$1.01			$4.40

(1) In connection with the Company’s April 2017 1-for-10 reverse stock split, the exercise price of the warrants was adjusted downward to $1.00 per share. In September 2017, the exercise price of the warrants was further adjusted downward to $0.57 per share in connection with the issuance of 523,210 shares of the Company’s common stock to the shareholders who were party to the Common Stock Issuance Agreement.  The exercise price of the warrants is subject to further adjustment upon future dilutive issuances of the Company’s common stock and stock combination events as defined in the warrant agreements (see Note 10).

June 2016 Offering Warrants [Member]

Derivatives And Fair Value [Line Items]

Valuation Assumptions Used

The assumptions used consisted of the following:

	December 31, 2017			December 31, 2016
Volatility		125	%		118	%
Expected term (years)		3.42			4.42
Risk-free interest rate		2.01	%		1.80	%
Dividend yield		0.00	%		0.00	%
Exercise price		$22.50			$22.50
Common stock closing price		$1.01			$4.40