Capital Stock - Additional Information (Detail) (USD $)	12 Months Ended			12 Months Ended			12 Months Ended			12 Months Ended		1 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Jun. 29, 2012	Dec. 31, 2012 Convertible Preferred Stock [Member]	Dec. 31, 2011 Convertible Preferred Stock [Member]	Dec. 31, 2012 Employee Stock Purchase Plan [Member]	Dec. 31, 2012 Warrant 2 [Member]	Dec. 31, 2012 Warrant 3 [Member]	Dec. 31, 2012 Pyxis Innovations Inc [Member]	Dec. 31, 2012 Series A-1 Preferred Stock [Member]	Jun. 29, 2012 Series A-1 Preferred Stock [Member]	Jun. 29, 2012 Series B Preferred Stock [Member]	Dec. 31, 2012 Series B Preferred Stock [Member]
Stockholders Equity [Line Items]
Convertible preferred stock, par value	$ 0.001	$ 0.001
Convertible preferred stock, shares authorized	6,000,000	6,000,000
Convertible preferred stock, shares issued	5,500,000	5,000,000								5,000,000	5,000,000	500,000	500,000
Convertible preferred stock, shares outstanding	5,500,000	5,000,000								5,000,000			500,000
Common stock, shares authorized	150,000,000	100,000,000											150,000,000
Common stock, par value	$ 0.001	$ 0.001											$ 0.001
Common stock, outstanding or reserved for issuance													85,644,185
Common stock, shares outstanding	36,761,864	36,709,706											36,761,864
Shares reserved for conversion of Preferred to common stock										28,160,200			10,928,961
Shares reserved for conversion of debt									2,521,222
Debt outstanding	$ 14,316,255
Shares reserved for potential exercise	4,334,780
Shares reserved for exercise of outstanding warrants			437,158				1,750,000	437,158
Warrants exercise price per share			0.2745				1.30	0.2745
Expiration date of warrants							Mar. 05, 2015	Jun. 29, 2017
Proceeds from private placement of preferred stock	3,000,000	0										3,000,000
Conversion of Series B convertible preferred Stock to Common Stock												21.86
Convertible preferred stock current conversion price										$ 0.3196		$ 0.2745	$ 0.2745
Net Proceeds from issuance of Series B Convertible preferred Stock												2,700,000
Warrants issued in connection with private placement of preferred stock	104,907
Accrued dividend rate	8.00%
Convertible preferred stock, liquidation preference	$ 24,000,000	$ 18,000,000								$ 18,000,000			$ 6,000,000
Convertible preferred stock, effective purchase price										$ 1.80			$ 6.00
Shares Reserved For Exercise Of Rights						750,000
Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount	46,099,541	34,827,685		39,089,161	28,160,200