Financial Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative liability	$ 830,000	$ 2,059,077
Conversion Options | 8% convertible promissory notes
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of derivative liability	610,000
Derivative liability	610,000	0	0
Warrant | 8% convertible promissory notes
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of derivative liability	220,000
Derivative liability	220,000	0	0
Placement Agent | Warrant
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative liability	81,716	487,555	0
Fair Value, Inputs, Level 3 | Conversion Options | 8% convertible promissory notes
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of derivative liability	610,000
Fair Value, Inputs, Level 3 | Warrant | 8% convertible promissory notes
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of derivative liability	220,000
Fair Value, Measurements, Recurring | Conversion Options
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of derivative liability		113,271
Fair Value, Measurements, Recurring | Warrant | 10% convertible preferred stock warrants
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of derivative liability		1,875,463
Fair Value, Measurements, Recurring | Bonus Warrants
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of derivative liability		70,343
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Derivative liability	830,000	2,059,077
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Conversion Options
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of derivative liability		113,271
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Warrant
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of derivative liability	81,716	487,555
Derivative liability	911,716	2,546,632
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Warrant | 10% convertible preferred stock warrants
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of derivative liability		1,875,463
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Bonus Warrants
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of derivative liability		70,343
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Placement Agent | Warrant
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]
Fair value of derivative liability	81,716	487,555
Derivative liability	$ 911,716	$ 2,546,632