Warrants (Detail) - Warrants outstanding (USD $)				12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Issued 9/26/2003 [Member]	Dec. 31, 2012 Issued 6/25/2008 [Member]	Dec. 31, 2012 Issued 10/15/2010 [Member]	Dec. 31, 2012 Issued 12/21/2010 [Member]	Dec. 31, 2012 Issued 12/22/2010 [Member]	Dec. 31, 2012 Issued 12/30/2010 [Member]	Dec. 31, 2012 Issued 7/5/2011 [Member]	Dec. 31, 2012 Issued 2/16/2012 [Member]	Dec. 31, 2012 Issued 7/27/2012 [Member]
Warrant Outstanding	923,090	929,914	942,870	7,577	9,859	616,245	25,000	128,333	25,000	61,076	5,000	45,000
Warrant Outstanding, Exercise Price (in Dollars per share)	$ 7.77	$ 15.13	$ 16.36	$ 48.90	$ 2.80	$ 7.92	$ 7.92	$ 7.92	$ 10.40	$ 4.50	$ 3.80	$ 2.09
Warrant Outstanding, Issuance Date				9/26/03	6/25/2008	10/15/2010	12/21/2010	12/22/2010	12/30/2010	7/5/2011	2/16/2012	7/27/2012
Warrant Outstanding, Expiration Date				9/25/2013	10/1/2014	10/15/2013	12/21/2013	12/22/2013	6/30/2016	6/28/2016	8/16/2017	7/27/2018