Stock Options and Stock Grants - Summary of Option Activity (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Outstanding, Number, Beginning Balance	2,094,000
Shares, Granted	568,000
Stock option exercises, Shares	(35,000)	(23,000)
Shares, Forfeited or expired	(187,000)
Outstanding, Number, Ending Balance	2,440,000	2,094,000
Shares, Exercisable	1,500,000
Shares available for grant	599,000
Weighted Average Exercise Price per Share, Beginning Balance	$ 1.30
Weighted Average Exercise Price per Share, Granted	$ 0.52
Weighted Average Exercise Price per Share, Exercised	$ 0.30
Weighted Average Exercise Price per Share, Forfeited or expired	$ 1.20
Weighted Average Exercise Price per Share, Ending Balance	$ 1.15	$ 1.30
Weighted Average Exercise Price per Share, Exercisable	$ 1.58
Weighted Average Remaining Contractual Term, Outstanding	6 years 6 months
Weighted Average Remaining Contractual Term Years, Exercisable	5 years 2 months 12 days
Aggregate Intrinsic Value, Outstanding	$ 45
Aggregate Intrinsic Value, Exercisable	$ 30