Summary of Warrant Activity (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Shares
Beginning Balance	7,424,241	6,673,405
Issued	5,000	1,379,739
Cancelled	(1,344,012)	(616,726)
Exercised	(50,000)	(12,177)
Ending Balance	6,035,229	7,424,241