Revenue (Detail) (USD $)	1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 31, 2010	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Revenue [Line Items]
Revenue		$ 214,000	$ 196,000	$ 359,000	$ 1,431,000
Small Business Innovative Research
Revenue [Line Items]
Revenue from Grants		214,000	196,000	359,000	461,000
Reduction of equipment cost basis purchased with grant funding		40,000	0	40,000	0
Remaining available amount under grant		785,000		785,000
Revenue				359,000	461,000
Vulcan Incorporated
Revenue [Line Items]
Grants received	20,000,000
Deferred revenue	8,200,000
Deferred Revenue, Revenue Recognized		$ 0	$ 0	$ 0	$ 970,000