Capital Stock - Additional Information (Detail) - USD ($)	1 Months Ended					12 Months Ended
	Aug. 25, 2016	Jul. 29, 2016	Dec. 23, 2014	Sep. 30, 2014	May 17, 2013	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Aug. 09, 2013
Stockholders Equity [Line Items]
Convertible preferred stock, par value						$ 0.001	$ 0.001
Convertible preferred stock, shares authorized						6,000,000	6,000,000
Common stock, shares authorized						450,000,000	300,000,000
Common stock, par value						$ 0.001	$ 0.001
Common stock, shares outstanding						229,381,059	172,887,221
Allocated Share-based Compensation Expense						$ 9,000	$ 12,000
Common Stock Shares Issued						229,381,059	172,887,221
Debt Conversion, Converted Instrument, Shares Issued						2,521,222
Interest Paid						$ 429,267	$ 467,500
Debt Conversion, Original Debt, Amount						14,316,255
May 2013 Private Placement [Member] | Minimum [Member]
Stockholders Equity [Line Items]
Common stock, shares authorized									150,000,000
May 2013 Private Placement [Member] | Maximum [Member]
Stockholders Equity [Line Items]
Common stock, shares authorized									300,000,000
Venture Loan [Member]
Stockholders Equity [Line Items]
Warrants exercise price per share			$ 0.1003
Class of Warrant or Right, Number of Securities Called by Warrants or Rights			2,492,523
Proceeds from Issuance of Long-term Debt			$ 5,000,000
Interest Paid						429,000	456,000
Paid-in-Kind Interest						294,000	153,000
Debt Instrument, Unamortized Discount						$ 579,000
Debt Restructuring 2016 [Member]
Stockholders Equity [Line Items]
Warrant Expiration Period	10 years
Debt Principal Amount Reduced Percentage	33.00%					33.00%			33.00%
Investor [Member]
Stockholders Equity [Line Items]
Sale of Stock, Consideration Received on Transaction		$ 5,600,000	$ 5,025,000
Sale of Stock, Number of Shares Issued in Transaction		56,262,571	50,099,700
Warrants exercise price per share		$ 0.0994	$ 0.1003
Sale of Stock, Price Per Share		$ 0.0994	$ 0.1003
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		56,262,571	50,099,700
Warrant Expiration Period		7 years	7 years
Danforth Advisors [Member]
Stockholders Equity [Line Items]
Common stock, par value				$ 0.25
Warrants Fair Value Disclosure						$ 24,000
Common Stock Shares Issued				100,000
Warrant Expiration Period				10 years
Common Stock [Member]
Stockholders Equity [Line Items]
Convertible Preferred Stock, Shares Issued upon Conversion						39,089,161
Common Stock [Member] | May 2013 Private Placement [Member]
Stockholders Equity [Line Items]
Sale of Stock, Consideration Received on Transaction					$ 12,000,000
Sale of Stock, Number of Shares Issued in Transaction					43,715,847
Sale of Stock, Price Per Share					$ 0.1003
Warrants 2013 [Member]
Stockholders Equity [Line Items]
Percentage Of Warrants Exercisable					63.00%
Percentage Of Warrants Exercisable After Shareholder Approval					37.00%
Warrants exercise price per share					$ 0.2745
Class of Warrant or Right, Number of Securities Called by Warrants or Rights					32,786,885
Warrants 2014 [Member]
Stockholders Equity [Line Items]
Warrants Fair Value Disclosure			$ 261,000
Warrants and Rights Outstanding								$ 5,200,000
Warrant Expiration Period			10 years
Warrants 2016 [Member]
Stockholders Equity [Line Items]
Warrants Fair Value Disclosure						$ 6,500,000
Lender Warrant 2016 [Member]
Stockholders Equity [Line Items]
Warrants exercise price per share						$ 0.0994
Class of Warrant or Right, Number of Securities Called by Warrants or Rights						5,169,577
Warrants and Rights Outstanding						$ 504,000
Lender Warrant 2016 [Member] | Venture Loan [Member]
Stockholders Equity [Line Items]
Interest Paid						429,000	$ 456,000
Placement Agent Warrants [Member]
Stockholders Equity [Line Items]
Allocated Share-based Compensation Expense						$ 780,000
Warrants To Purchase Of Common Stock						2,295,082
Warrants exercise price per share						$ 0.2745
Class of Warrant or Right, Number of Securities Called by Warrants or Rights			89,731
Warrants and Rights Outstanding								$ 9,000
Payments for Underwriting Expense			$ 218,000			$ 63,000