Capital Stock - Additional Information (Detail) (USD $)	0 Months Ended	1 Months Ended	3 Months Ended				1 Months Ended	3 Months Ended		3 Months Ended				3 Months Ended				1 Months Ended	3 Months Ended		3 Months Ended
	Aug. 09, 2013	May 17, 2013	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Jun. 29, 2012	May 17, 2013 Common Stock [Member]	Mar. 31, 2014 Common Stock [Member]	Mar. 31, 2014 Employee Stock Purchase Plan [Member]	Mar. 31, 2014 Warrant 1 [Member]	Mar. 31, 2014 Warrant 2 [Member]	Mar. 31, 2014 Warrant 3 [Member]	Jun. 29, 2012 Warrant 4 [Member]	Mar. 31, 2014 Series A-1 Preferred Stock [Member]	May 17, 2013 Series A-1 Preferred Stock [Member]	Jun. 29, 2012 Series A-1 Preferred Stock [Member]	Jun. 29, 2012 Series A-1 Preferred Stock [Member] Pyxis Innovations Inc [Member]	Jun. 29, 2012 Series B Preferred Stock [Member]	Mar. 31, 2014 Series B Preferred Stock [Member]	May 17, 2013 Series B Preferred Stock [Member]	Mar. 31, 2014 Placement Agent Warrants [Member]	Aug. 09, 2013 Placement Agent Warrants [Member]	Jun. 30, 2013 Placement Agent Warrants [Member]	May 17, 2013 Placement Agent Warrants [Member]
Stockholders Equity [Line Items]
Convertible preferred stock, par value			$ 0.001
Convertible preferred stock, shares authorized			6,000,000
Convertible preferred stock, shares issued																5,000,000	5,000,000	500,000
Common stock, shares authorized		150,000,000	300,000,000	300,000,000	150,000,000
Common stock, par value			$ 0.001	$ 0.001
Common stock, outstanding or reserved for issuance			198,379,556
Common stock, shares outstanding			122,481,674	122,448,707
Shares reserved for conversion of Preferred to common stock														28,160,200
Shares reserved for potential exercise			6,146,700
Shares reserved for exercise of outstanding warrants										1,750,000	437,158	35,081,967	437,158
Warrants exercise price per share		0.2745				0.2745				1.30	0.2745	0.2745	0.2745								0.2745
Expiration date of warrants										Mar. 05, 2015	Jun. 29, 2017
Proceeds from private placement of preferred stock		$ 12,000,000					$ 12,000,000											$ 3,000,000
Convertible preferred stock current conversion price			$ 0.3196
Net Proceeds from issuance of Series B Convertible preferred Stock																		2,700,000
Convertible preferred stock, liquidation preference		24,000,000													18,000,000					6,000,000
Convertible preferred stock, effective purchase price														$ 1.80					$ 6.00
Shares Reserved For Exercise Of Rights									605,920
Class Of Warrant Or Right Exercisable Number Of Warrants Or Rights		32,786,885										20,655,737
Warrant Exercisable Expiration Date												May 17, 2020
Shares Reserved For Issuance Of Common Stock And Warrants			31,876,137
Additional Pro Rata InvestmentIn Common Stock And Warrants			5,000,000					5,000,000
Fair Value Adjustment of Warrants			104,907
Conversion of Stock, Shares Converted			39,089,161																10,928,961
Convertible Preferred Stock, Shares Issued upon Conversion								39,089,161
Stock Issued During Period Shares New Issues							43,715,847
Share Price							$ 0.2745
Percentage Of Warrants Exercisable			63.00%
Percentage Of Warrants Exercisable After Shareholder Approval			37.00%
NoncashInterest Expense																					286,579
Increase In Common Stock Shares Authorized	300,000,000	300,000,000
Increase In Interest Expense	11,000
Allocated Share-based Compensation Expense																					780,000
Warrants To Purchase Of Common Stock																					2,295,082
Warrants Fair Value Disclosure																						$ 5,369,676	$ 5,358,708	$ 5,072,129