Warrants (Tables)

9 Months Ended

Sep. 30, 2012

Warrants [Abstract]

Number of Warrants Outstanding

The number of warrants outstanding at September 30, 2012 and December 31, 2011 were as follows:

	September 30, 2012		December 31, 2011
Liability-classified warrants		8,050,709		8,424,905
Equity-classified warrants		3,146,745		4,692,359
Total warrants		11,197,454		13,117,264

Assumptions Used In Binomial Valuation Model and Black-Scholes Valuation Model

The following assumptions were used in the Binomial/Monte Carlo valuation model at September 30, 2012 and the Black-Scholes valuation model at September 30, 2011:

	September 30, 2012		September 30, 2011
Risk-free interest rate		0.23%		0.08 - 0.47%
Expected life in years		2.19		0.67 - 3.18
Expected volatility		70%		48.9 - 95.5%
Expected dividend yield		0		0
Steps per year		12		N/A

Warrant Exercises

During the nine months ended September 30, 2012, warrant exercises were as follows:

(in thousands, except share data)	Equity Warrants		Liability Warrants		Common Stock Issued		Liability Reclassed to Equity		Cash Received
Cash exercises		161,639		-		161,639	$	-	$	330
Cashless exercises		24,658		373,617		98,021		412		-
		186,297		373,617		259,660	$	412	$	330

During the nine months ended September 30, 2011, warrant exercises were as follows:

(in thousands, except share data)	Equity Warrants		Liability Warrants		Common Stock Issued		Liability Reclassed to Equity		Cash Received
Cash exercises		2,311,585		-		2,311,585	$	-	$	12,399
Cashless exercises		39,832		165,551		65,986		303		-
		2,351,417		165,551		2,377,571	$	303	$	12,399