Effect on Consolidated Statement of Cash Flows (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Cash flow from operating activities:
Net income (loss)	$ (5,433,127)	$ (10,963,326)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of convertible debt discount	510,220	567,575
Loss on debt extinguishment	0	(1,350,000)
Fair value of bonus warrants at debt extinguishment	0	(797,185)
Change in fair value of derivative liabilities	1,171,419	(1,377,960)
Share-based compensation	673,617	3,046,202
Net cash used in operating activities	(6,206,712)	(4,940,241)
Scenario, Previously Reported
Cash flow from operating activities:
Net income (loss)		(9,937,268)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of convertible debt discount		692,685
Loss on debt extinguishment		0
Fair value of bonus warrants at debt extinguishment		0
Change in fair value of derivative liabilities		1,870,071
Share-based compensation		3,280,933
Net cash used in operating activities		(4,940,241)
Scenario, Previously Reported | Bonus Warrants
Adjustments to reconcile net loss to net cash used in operating activities:
Change in fair value of derivative liabilities		1,870,071
Restatement Adjustment
Cash flow from operating activities:
Net income (loss)		(1,026,058)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of convertible debt discount		(394,285)	[1]
Loss on debt extinguishment		1,350,000	[2]
Fair value of bonus warrants at debt extinguishment		797,185	[3]
Change in fair value of derivative liabilities		(492,111)
Share-based compensation		(234,731)	[4]
Net cash used in operating activities		0
Restatement Adjustment | Bonus Warrants
Adjustments to reconcile net loss to net cash used in operating activities:
Change in fair value of derivative liabilities		$ (492,111)

[1] to reverse the improper amortization of debt discount.

[2] to record the difference between the reacquisition price of the new debt and the net carrying amount of the extinguished debt at the amendment date.

[3] to record the fair value of the bonus warrants as of the amendment date as a component of the reacquisition price of the new debt.

[4] to reverse the impact of the improper recording of the fair value of the Bonus Warrants upon issuance.