Description of Business and Summary of Significant Accounting Policies - Additional Information I (Detail) (USD $) Share data in Millions, unless otherwise specified	3 Months Ended		12 Months Ended			83 Months Ended		12 Months Ended	1 Months Ended	3 Months Ended		12 Months Ended			83 Months Ended	1 Months Ended	12 Months Ended		83 Months Ended	12 Months Ended		3 Months Ended		12 Months Ended			37 Months Ended	83 Months Ended	1 Months Ended	12 Months Ended	83 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2014	Dec. 31, 2012	Dec. 31, 2011	Mar. 31, 2014	Dec. 31, 2013 sqft	Mar. 31, 2014 Third party [Member]	Oct. 31, 2011 Research and Development Services [Member]	Mar. 31, 2013 Research and Development Services [Member]	Mar. 31, 2012 Research and Development Services [Member]	Mar. 31, 2014 Research and Development Services [Member]	Dec. 31, 2012 Research and Development Services [Member]	Dec. 31, 2011 Research and Development Services [Member]	Mar. 31, 2014 Research and Development Services [Member]	Dec. 31, 2010 12 month research contract agreement [Member]	Dec. 31, 2012 12 month research contract agreement [Member]	Dec. 31, 2011 12 month research contract agreement [Member]	Mar. 31, 2014 12 month research contract agreement [Member]	Mar. 31, 2014 U.S. Treasury [Member]	Dec. 31, 2010 U.S. Treasury [Member] Grants	Mar. 31, 2013 NHLBI [Member]	Mar. 31, 2012 NHLBI [Member]	Mar. 31, 2014 NHLBI [Member]	Dec. 31, 2012 NHLBI [Member]	Dec. 31, 2011 NHLBI [Member]	Dec. 31, 2012 NHLBI [Member] Grants	Mar. 31, 2014 NHLBI [Member]	Aug. 31, 2013 Private, not-for-profit organization [Member]	Mar. 31, 2014 Private, not-for-profit organization [Member]	Mar. 31, 2014 Private, not-for-profit organization [Member]	Dec. 31, 2013 Maximum [Member]	Mar. 31, 2014 Maximum [Member]	Mar. 31, 2014 Minimum [Member]
Significant Accounting Policies Related To Business Acquisition Revenue Recognition And Earnings Per Share [Line Items]
Maturity of highly liquid investment																																90 days
Restricted cash	$ 88,000		$ 79,000	$ 88,000		$ 79,000
Restricted cash held in certificates of deposit	38,300		78,800	38,300		78,800
Increase in rented area							15,268
Additional restricted cash	50,000			50,000
Allowance for doubtful amounts			0			0
Inventory of raw materials, net of reserves	88,000		63,000	104,000		63,000
Inventory of finished goods				196,000
Inventory of work-in-progress				60,000
Obsolete inventory reserve	0		31,000	0		31,000
Estimated useful life of the fixed assets			The estimated useful lives of the fixed assets range between two and five years.
Useful life of fixed assets, range																																	5 years	2 years
Impairment of long-lived assets			0
Deferred revenue related to its collaborative research programs	53,000		13,000			13,000				62,000		17,000	0		17,000
Term of research contract agreement with third party																12 months
Research and development services on a fixed-fee basis									1,365,000							600,000
Total revenue recognized from inception on the contract	215,000	120,000	379,000	1,197,000	969,000	3,442,000									1,405,000		150,000	450,000	600,000
Initial payment to company from agreement									239,000
Remaining payments expected to occur over									21 months
Fee for additional research and development services			135,000					40,000
Total potential contract value			1,500,000					1,405,000
Maximum amendment extended period remaining for payment of additional research and development services												28 months
Revenue related to research contract										97,000	120,000	184,000	885,000	239,000
Number of grants issued																					2						3
Revenue recognized under grants	117,000		131,000	162,000	57,000	1,074,000														397,000		117,000	0	12,000	162,000	57,000	558,000	558,000	251,700	119,000	119,000
Dilutive effect	$ 0	$ 0	$ 0	$ 0	$ 0
Total common stock equivalents excluded from computing diluted net loss per share	8.9	25.8	7.7	15.2	6.4