Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	3 Months Ended		45 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016
Accounting Policies [Abstract]
Impairment of investments	$ 0
Based on these sales prices reduced inventory and increased cost of goods sold	544,000	$ 252,000
Revenue recorded from government contract	97,000	$ 141,000	$ 4,100,000
Total value of the contract	$ 4,700,000		$ 4,700,000
Period of contract	3 years
Number of outstanding warrants	0		0